OH AIRCRAFT ENGINE GROUP F/6 20/1 292 HIGH VELOCITY ...2" 11* v o~ftz j & nr, source locamzw amu 2...

148
AD-AD94 292 GENERAL ELECTRIC Co CINCINNATI OH AIRCRAFT ENGINE GROUP F/6 20/1 HIGH VELOCITY JET NOISE SOURCE LOCATION AND REDUCTION. TASK 2 S--ETC(U) MAY 78 P R GLIEBE DOT-OS-30034 UNCLASSIFIED R78AEGFAA-.RD76-79-2A NL

Transcript of OH AIRCRAFT ENGINE GROUP F/6 20/1 292 HIGH VELOCITY ...2" 11* v o~ftz j & nr, source locamzw amu 2...

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AD-AD94 292 GENERAL ELECTRIC Co CINCINNATI OH AIRCRAFT ENGINE GROUP F/6 20/1

HIGH VELOCITY JET NOISE SOURCE LOCATION AND REDUCTION. TASK 2 S--ETC(U)MAY 78 P R GLIEBE DOT-OS-30034

UNCLASSIFIED R78AEGFAA-.RD76-79-2A NL

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PHOTOGRAPH THIS SHEET

LEVEL .NV ,tO RYWMRAL ELERTRIC. C~lt CWNATS 4 AIRCSOY

2" 11* V o~ftz J & Nr, SOURCE LOCAMZW AMU2 REDUCTIONW TASK 2a., SUPPLEMENT - COMPUTER PROGRAM FORd CALCULATING IR ARoAGo(nTIC rHARArPT-RISTICS OF JETS FROM NOZZLE

O DOCUMENT IDENTIFICATIONdt OF ARBITRARY SHAPE" FINAL REPT., MAY 78, REPT. NO. R78AEG324

CONTRACT DOT-OS-30034 FAA.RD.76.79.2a.SUPPL

IDI$TRIB I~ STATEM FN1 hApproved for public release;

Distribution Unlimited

DISTRIBUTION STATEMENT

ACCESSION FOR

NTIS GRA&I DTICDTIC TAB 5UNANNOUNCED 5l ELECTEJUSTIFICATION m

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Report No. FAA-RD-76-79, lia R78AEG324

HIGH VELOCITY JET NOISESOURCE LOCATION AND REDUCTION

TASK 2 SUPPLEMENT - COMPUTER PROGRAMSFOR CALCULATING THE AEROACOUSTIC CHARACTERISTICS

OF JETS FROM NOZZLES OF ARBITRARY SHAPE

TECHNICAL CONTRIBUTOR:

0 P.R. Gliebe

GENERAL ELECTRIC COMPANYAIRCRAFT ENGINE GROUPCINCINNATI, OHIO 45215

SIATIO '0

MAY 1978

FINAL REPORT

Document is available to the public through theNational Technical Information Service,

Springfield, Virginia 22151

Prepared for

U.S. DEPARTMENT OF TRANSPORTATIONFEDERAL AVIATION ADMINISTRATION

Systems Research & Development ServiceWashington, D.C. 20590

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NOTICE

The contents of this report reflect the views of the General Electric Companywhich is responsible for the facts and the accuracy of the data presented

herein. The contents do not necessarily reflect the official views or policyof the Department of Transportation. This report does not constitute astandard, specification or regulation.

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1. Report No. 2. Government Accession No. 3. Recipient's Catalog No.

FAA-RD-76-79, Ila

4. Title and Subtitle 5. Report Date(lICH VELOCITY JET NOISE SOURCE LOCATION AND REDUCTION May 1978TASK 2 SUPPLEIENT - COMPUTER PROGIAM FOR CALCULATING THE AERO- 6. Performing Organization CodeACOUSTIC CHARACTERISTICS OF JETS FROM NOZZLES OF ARBITRARYSHAPE

7. Author(s) 8. Performing Organization Report No.

P.R. Gliebe R78AEG324

________________________________________________________10. Work Unit No.9. Performing Organization Name and Address

General Electric Company 11. Contract or Grant No.Group Advanced Engineering Division nAircraft Engine Group DOT-OS-30034Cincinnati, Ohio 45215 13. Type of Report and Period Covered

12. Sponsoring Agency Name and Address Task 2 Supplement

U.S. Department of Transportation October 1977Federal Aviation Administration 14. Sponsoring Agency CodeSystems Research and Development Service 5ashington, D.C. 20590 ARD-550

15. Supplementary Notes This report is in partial fulfillment of the subject program. Related documentsto be issued in the course of the program iaclude final reports of the following tasks: Task 1 - iActivation of Facilities and Validation of Source Location Techniques; Task 1 Supplement - Certi-fication of the General Electric Jet Noise Anechoic Test Facility; Task 2 - Theoretical Develop-ments and Basic Experiments; Task 3 - Experimental Investigation of Suppression Principles; Task 4Development/Evaluation of Techniques for "Inflight" Investigation; Task S - Investigation of"Inflight" Aeroacoustic Effects; Task 6 - Noise Abate Nozzle Design Guide.

16. Abstract

A computational procedure is presented for predicting the aerodynamic and acoustic character-istics of jets from nozzles of arbitrary shape. The procedure treats the jet plume as a col-lection of uncorrelated multipole sound sources which convect with the flow. The aerodynamiccharacteristics of the jet are evaluated utilizing an extension of Reichardt's theory for freeturbulent flows. The acoustic radiation from each of the sound sources is evaluated from high-frequency asymptotic solutions of Lilley's equation. The jet plume is subdivided into severalhundred elemental volume sources, each roughly the size of a turbulent eddy volume. Thecorrelated sound level spectra of the individual eddy volumes are summed on a mean-squarepressure basis to yield the total turbulent mixing noise levels. An auxiliary calculation ofshock-cell broadband noise is made and added to the turbulent mixing noise spectrum to give thetotal farfield noise. A description of the computational model and associated computer programis presented herein, along with a sample of input and output. A FORTRAN listing of the computerprogram is also included.

17. Key Words (Suggested by Authorls)) 18. Distribution Statement

M*G*B Doument is available to the public throughJet Noise, Suppressors, Jet Flows, Turbulence, ce istval al tot ic trough

Acoutic, Prdicion ~thd Ithe National Technical Information Service,Acoustics, Predict ion Method Springfield, Virginia

19. Security Claiif. (of this report) ( 20. Security Claulf, (of this pagel 21. No. of Pages 22. Price*

UNCLASSI F IED JNCLSSIFIED 142

For sale by the National Technical Information Service, Springfield, Virginia 22151

NASA-C-16 (R"" 6-71)

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PREFACE

This report describes the work performed under Task 2 of the DOT/FAAHigh Velocity Jet Noise Source Location and Reduction program (ContractDOT-OS-30034). The objectives of the program were:

0 Investigation of the aerodynamic and acoustic mechanisms of variousjet noise suppressors, including scaling effects

0 Analytical and experimental studies of the acoustic source distri-bution in such suppressors, including identification of sourcelocation, nature and strength and noise reduction potential

* Investigation of inflight effects on the aerodynamic and acousticperformance of these suppressors.

The results of these investigations lead to the preparation of a designguide report for predicting the overall characteristics of suppressor con-cepts from models to full-scale static, to inflight conditions, as well as aquantitative and qualitative prediction of the phenomena involved.

The work effort in this program was organized under the following majorTasks, each of which is reported in a separate final report:

Task 1 - Activation of Facilities and Validation of Source LocationTechniques.

Task 2 - Theoretical Developments and Basic Experiments.

Task 3 - Experimental Investigation of Suppression Principles.

Task 4 - Development and Evaluation of Techniques for Inflight Investi-gation.

Task 5 - Investigation of Inflight Aero-Acoustic Effects on SuppressedExhausts.

Task 6 - Preparation of Noise Abatement Nozzle Design Guide Report.

Task 1 was an investigative and survey effort designed to identifyacoustic facilities and test methods best suited to jet noise studies. Task2 was a theoretical effort complemented by theory verification experimentswhich extended across the entire contract period of performance.

This volume is a supplement to the Task 2 report, documenting a generalmethod for predicting the aerodynamic and acoustic behavior of turbulent

jets. The objective of the report is to provide users with a description ofthe method and associated computational procedure in sufficient detail thatit can be implemented and utilized as a useful engineering tool.

ili

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Task 3 represented a substantial contract effort to gather various testdata on a wide range of high velocity jet nozzle suppressors. These data,intended to help identify several "optimum" nozzles for inflight testingunder Task 5, provide an extensive high quality data bank useful to prepara-tion of the Task 6 design guide as well as to future studies.

Task 4 was similar to Task 1, except that it dealt with the specific

test facility requirements, measurement techniques and analytical methodsnecessary to evaluate the inflight noise characteristics of simple and com-plex suppressor nozzles. This effort provided the capability to conduct the"flight" effects test programs of Task 5.

iv

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TABLE OF CONTENTS

Section Page

1.0 SUMMARY 1

2.0 INTRODUCTION 2

3.0 ANALYSIS 4

3.1 Outline of Method 4

3.2 Flow Field Prediction 73.3 Turbulent Mixing Noise Prediction 11

3.4 Shock-Cell Noise Prediction 15

3.5 Aeroacoustic Model Integration 18

4.0 COMPUTER PROGRAM DESCRIPTION 21

4.1 Introduction 21

4.2 Program Nomenclature and Symbol Convention 22

4.3 Description of Program and Subroutines 25

4.4 Program Usage and Logic 40

5.0 CONCLUDING REMARKS 42

APPENDIX A - DESCRIPTION OF INPUT 43

APPENDIX B - DESCRIPTION OF OUTPUT 59

APPENDIX C - SAMPLE OUTPUT LISTING 61

APPENDIX D - COMPUTER PROGRAM SOURCE LISTING 95

REFERENCES 130

V

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LIST OF ILLUSTRATIONS

Figure Page

1. Typical Jet Plume Exhausting from a Nozzle of Arbitrary

(Noncircular) Planform Shape. 5

2. Typical Jet Plume Flow Field Subdivision into Eddy VolumeElements (Not to Scale). 6

3. Block Diagram of Jet Noise Aeroacoustic Prediction Model. 8

4. Possible Solution Types for a Maximum of Two TurningPoints. 13

5. Empirical Model of Shock Cell Noise Component of Spectrum. 16

6. FORTRAN Symbol Convention for Coordinates and GeometricVariables. 23

7. FORTRAN Symbol Convention for Acoustic Arena Variables. 24

8. Computer Program Flow Chart. 34

A-l. Examples of How Boundary Parameters are Specified. 53

A-2. Centerbody Input Coordinate Examples. 54

A-3. Example Demonstration of Nozzle Geometry Specificationwith a Generalized Nozzle Exit Configuration. 55

vii

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LIST OF TABLES

Table Page

1. Shielding Coefficients aij. 15

2. List of FORTRAN Symbols. 26

A-I. Suggested Input Format. 44

A-2. Input Variable Definitions. 46

A-3. Preset Input Values. 50

C-1. Input Data Card Listing Sample Case. 62

viii

k .. , .. .. AMl- ll

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VSYMBOLS

A. - jet nozzle exhaust area

AR - outer-to-inner stream area ratio

a - (x-x) quadrupole directivity factorxxay - (x-y) quadrupole directivity factor

ayy - (y-y) quadrupole directivity factor

ayz - (y-z) quadrupole directivity factor

bh - enthalpy mixing layer thicknessbm - momentum mixing layer thickness

C - convective amplification factor

Ch - enthalpy mixing layer spreading parameter

C. - jet exit plane speed of sound

Cm - momentum mixing layer spreading parameter

Ca - ambient speed of sound

Cp - specific heat at constant pressure

CI - empirical constant in spreading parameter equation

C2 - empirical constant in spreading parameter equation

Deq - equivalent area nozzle diameter 4Aj/7T

Dh - nozzle hydraulic diameter 4Aj/P w

f - observed frequency

fp - peak-noise observed frequency

g2 (r) - shielding function

H - stagnation enthalpy relative to ambient

I(S) - source intensity spectrum

k - source wave number Q/Ca

Lavg - average shock cell spacing

M - flow Mach number U/Ca

Ma - ambient (windtunnel or flight) Mach number

Mc - eddy convection Mach number Uc/Ca

Mj - jet nozzle exit plane Mach number U j/Ca (also U /C. for shock

noise prediction)

Mm - postmerged region potential core Mach number

MO - Mach number at source location, M(r o )

N - number of shock cells

OASPL - overall sound pressure level, dB re 0.0002 p-bar

ix

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PNL - perceived noise level, dB re 0.0002 p-bar

PR - nozzle stagnation-to-ambient static pressure ratio

PWL - power watt level, dB re 10-13 watts

Pw - wetted perimeter of nozzle contour

Pa - ambient static pressure

p - mean-square acoustic pressure

R - source-to-observer distance

Ro - flow field calculation transverse coordinate

Rg - gas constant (1716 lbf-ft/slug-0 R)

r - radial coordinate

rb(x) - centerbody radius

ro - radial source location

ro - radial turning point location

SPL - sound pressure level, dB re 0.0002 w-bar

SPLP - peak value of SPL 1/3-octave spectrum

T - flow static temperature

Ta - ambient static temperature

TT - flow stagnation temperature

TTj - nozzle exit jet stagnation temperature

TR - outer-to-inner stream temperature ratio

U - local mean flow velocity

Ua - ambient (wind-tunnel or flight) velocity

Uc - eddy convection speed

Uj - jet exit plane velocity

Um - postmerged potential core velocity

Uo - mean flow velocity at source location

ut - axial turbulence velocity (r.m.s. intensity)

Vj - ideally expanded jet velocity

VR - outer-to-inner stream velocity ratio

x - axial coordinate

y - vector location of eddy volume in ift

a - coefficient in acoustic calculation; also angular coordinate ofnozzle boundary contour

at - turbulent decay parameter in convective amplification factor

L -

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B - shock strength parameter

-xx (x-x) quadrupole shielding factor

Bxy - (x-y) quadrupole shielding factor

Byy - (y-y) quadrupole shielding factor

Byz - (y-z) quadrupole shielding factor

B0 1 - shielding factor for case (c)

B02 - shielding factor for case (e)

B12 - shielding factor for case (f)

Bt - axial shear stress weighting factor

y - ratio of specific heats

Ar - transformed radial coordinate

Av - transformed boundary radius

6t - aximuthal shear stress weighting factor

e - observer angle relative to jet axis

ei - observer angle relative to inlet axis, 6i = 180* - e

it - characteristic time-delay azimuthal weighting factor

Vo - radial coordinate of nozzle boundary contour

P - flow mean density

Pa - ambient density

Pj - jet exit plane density

To - characteristic time-delay

TX - axial shear stress

Tr - radial shear stress

- azimuthal shear stress

- flow field calculation azimuthal coordinate

- azimuthal angular coordinate

- enthalpy function

- source radian frequency

- observer radian frequency

Subscripts

a - ambient condition

ann - referring to annulus property

b - centerbody parameter

xi

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c - convection property

eq - equivalent condition

g - gas property

h - referring to enthalpy or heat transport

i - referring to component in i-direction; also, referenced to inletaxis

j - referring to jet exit plane condition

m - referring to momentum transport; also, postmerged condition

o - referring to source location condition

p - peak noise value

r - radial component

T - stagnation condition

t - referring to a turbulence parameter

x - axial component

xx - referring to (x-x) quadrupole property

xy - referring to (x-y) quadrupole property

yy - referring to (y-y) quadrupole property

yz - referring to (y-z) quadrupole property

a - referring to turning point property

- azimuthal component

xii

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1.0 SUMMARY

This report represents a supplemental Task 2 effort under ContractDOT-OS-30034 documenting the computerized jet noise prediction method. Acomplete description of the computer program is provided, including examplesof input preparation, output cases, and a listing of the FORTRAN computercode. The mathematical model is briefly summarized (it appears in detail inthe Task 2 report proper).

A unified aerodynamic/acoustic prediction technique has been developedfor assessing the noise characteristics of suppressor nozzles. The techniqueutilizes an extension of Reichardt's method to provide predictions of the jetplume flow field (velocity, temperature and turbulence intensity distribu-tions). The turbulent fluctuations produced in the mixing regions of the jetare assumed to be the primary source of noise generation, as in the classicaltheories of jet noise. The alteration of the generated noise by the jetplume itself as it propagates through the jet to the far-field observer(sound/flow interaction or fluid shielding) is modelled utilizing the high-frequency shielding theory based on Lilley's equation.

These basic modelling elements (flow field prediction turbulent mixingnoise generation, and sound/flow interaction) have been coupled together ina discrete volume-element formulation. The jet plume is divided into ele-mental volumes, each roughly the size of a representative turbulence cor-relation volume appropriate to that particular location in the plume. Eachvolume element is assigned its own characteristic frequency, spectrum, andacoustic intensity. The sound/flow interaction effects for each volume ele-ment are evaluated from the flow environment of the element. The individualvolume elements are assumed to be uncorrelated with each other, so that thetotal contribution to the far field is simply the sum of the individualvolume element contributions.

The aero-acoustic model discussed herein is directed toward predictionof high velocity jet noise (1500 - 3000 feet per second), for arbitrarynozzle shapes, including sound pressure level spectra at any observer loca-tion.

The model in its present form does have certain limitations. Formultielement configurations, all elements must be parallel and non-impinging. In addition, the flow field calculation assumes constant staticpressure mixing, so that multichute or multitube nozzles with significant basepressure variations will not be properly simulated. This limitation is importantfor closely-spaced nozzle elements. Finally, the shock-cell noise portion of the

prediction is likely to be inadequate for multielement and/or multiflow con-figurations.

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2.0 INTRODUCTION

Many jet noise suppressor nozzles have been designed utilizing intuitivenotions of how to suppress jet noise, and have demonstrated substantial noisereduction, although often at the expense of considerable thrust loss,increased engine weight, manufacturing cost and complexity. Seemingly minorchanges in suppressor nozzle design, for the purpose of improving thrust per-formance, often result in substantial loss of noise suppression. It is there-fore highly desirable to have available a quantitative prediction techniquefor estimating the aerodynamic and acoustic characteristics of suppressor-typenozzle configurations, so that design and optimization studies can be madeprior to construction and testing in order to minimize the time and cost ofdevelopment. This technique should ideally be sensitive to the controllabledesign variables, and should be based on a minimum of empiricism. Anyempiricism employed should be tied more or less to physical (flow and acousticpropagation) characteristics rather than geometric parameters, i.e., it shouldbe "universal" in a normalized (but perhaps restricted) sense.

Previous work on modelling of jet aero-acoustic characteristics has beenconfined to simple round and coannular jets. One of the first attempts atdeveloping a comprehensive aerod.ynamic acoustic jet model was published byLee, Kendall, et al., Reference (1), and Grose and Kendall, Reference (2).This approach utilized an extension of Reichardt's method for predicting thejet flow properties (this method is adopted herein and in Reference 3) forround and lobe-type nozzles. Acoustic power spectra are predicted inReference (1) and (2), based on a "slice-of-jet" model wherein the power peraxial slice is computed and related to a certain frequency band by means ofempirically-derived frequency versus axial distance relations. Successful pre-dictions are confined to low Mach numbers. A volume-element summation ("lump-of-jet") approach was first developed by Benzakein et al., Reference (4), forround and coannular jets. A finite-difference turbulent-kinetic-energy modelwas developed therein to predict the jet flow field, while the classicalLighthill (5) and Ffowcs-Williams (6) formulations were employed, with suit-able empirical modifications, to predict the noise from each volume element.Extensions of the method of Benzakein et al. (4) to distinguish between self-noise and shear-noise, proposed by Jones (7) and Ribner (8), were developed byKnott (9) and Moon (10). Recently, Chen (11) has applied Kendall's method(2) to predicting power spectra of coannular jets.

The above methods either ignore the sound/flow interaction effects com-pletely, or recognize only source convection in absence of a shrouding flow,which has been shown to give incorrect simulation (see Mani, Reference 12) forall but the lowest jet velocities, especially when predicting sound pressurelevel spectra at observer angles close to the jet axis. The aero-acousticmodel discussed in this report is directed toward prediction of high velocityjet noise (1500 - 3000 fps), for arbitrary nozzle shapes, including soundpressure level spectra at any observer location.

2

__

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Section 3 summarizes the mathematical model (which is presented in de-tail in Reference 3) and Section 4 describes the computer program. A descrip-tion of inputs to the computer program is presented in Appendix A and a des-cription of the outputs is presented in Appendix B. Appendices C and D con-tain a sample output and a computer source listing for the program, respec-tively.

3

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3.0 ANALYSIS

3.1 OUTLINE OF METHOD

Consider a jet plume exhausting from a nozzle of arbitrary shape, asshown in Figure 1. Utilizing the modified Reichardt theory described inReference (3), the mean velocity, temperature, density and turbulent shearstress distributions can be computed throughout the jet plume. The requiredinputs are nozzle shape, nozzle exit plane total pressures and temperatures,and ambient total and static pressures and temperatures.

The jet plume is subdivided into elemental volumes which are approxi-mately the size of a typical turbulent correlation volume or "eddy size". Themodified Reichardt theory can provide the aerodynamic properties at any arbi-trary point in the plume because of the closed-form solution formulation (thecalculation is not a finite-difference method whose grid points are estab-lished/ dictated by the accuracy/stability requirements of the numericalprocedure). The flow properties are therefore computed at the geometriccenters of these eddy volume elements.

The noise generated by each of the volume elements is estimated from the

classical Lighthill (5) expressions for noise produced by free turbulence,assuming that the turbulence can be modeled as locally-isotropic, convectingquadrupole sources of sound, as proposed by Ribner (8). The turbulent struc-ture parameters (intensity, length-scale, characteristic frequency, spectrum)required for computing the generated noise are derived from the calculatedmean-flow distributions using previously established empirical similarityrelations, developed by Davies et al. (13).

For each volume element, the effect of convection and fluid shielding on

the emitted sound of that element is computed. The flow properties in thevicinity of the element, i.e., mean velocity profiles and temperature profiles,determine the amount of flow shrouding or fluid shielding seen by that ele-ment. From the generated noise spectrum and the predicted convection andfluid shielding, the net emitted noise level, at each observer angle and 1/3-octave band frequency of interest, is calculated. The contributions fromeach volume element in the jet are summed on a mean-square pressure basis,assuming that individual volume elements are uncorrelated with each other, toprovide the total 1/3-octave spectrum observed in the far field sound pres-sure.

A typical example of how a jet plume is subdivided into "eddy" volumeelements is illustrated in Figure 2. The subdivisions are very small close tothe nozzle exit plane where the turbulence length-scales are small, and thevolume elements are made progressively larger in the downstream direction,simulating the increasing length-scale with downstream distance.

4

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p ,Ua a

Pi FU i r Flow FieldPoint (x,r, )

P ,P,Uj.

i a yoit (V0 ,

(b) Typical Suppressor Nozzle Exit PlanePlanform Shape and Nomenclature

r

x

(a) Jet Plume Coordinate System

Figure 1. Typical Jet Plume Exhausting from a Nozzle of Arbitrary(Noncircular) Planform Shape.

5

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x

Figure 2. Typical Jet Plume Flow Field Subdivision (Not to Scale)

into Eddy Volume Elements.

6

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In addition to the calculation of turbulent mixing noise, the shock-cellbroadband noise is also computed using a modification of the Harper-Bourne/Fisher method, Reference (14), as described in Reference (3). The mixingnoise spectra and the shock-cell noise spectra are summed on a mean-squarepressure basis to yield the total jet noise spectra, at each far-field obser-ver angle.

A block diagram of the computation sequence for the jet noise predictionjust described is shown in Figure 3. Note also that atmospheric attenuationcorrections, using the method of Reference (15), are made to the predictedspectra to account for air attenuation at the appropriate far-field distance.From the far-field sound pressure spectra, the overall sound pressure levels(OASPL), perceived noise levels (PNL) and sound power spectrum (PWL) are alsoevaluated.

3.2 FLOW FIELD PREDICTION

The jet plume flow field is computed using the extension of Reichardt'smethod developed in Reference (3). The method basically consists of pre-dicting the diffusive transport of momentum flux and enthalpy flux from aspecified exit plane distribution to various axial stations along the plume.In addition, the various components of turbulent shear stress are also calcu-lated, being related to directional derivatives of the axial component ofmomentum flux. From these distributions, the mean axial velocity, density andturbulence intensity distributions are estimated.

A typical suppressor nozzle planform shape at the nozzle exit plane isshown in Figure 1. The nozzle contour can be defined by coordinates (vo, a).The jet nozzle exit plane conditions are denoted by subscript "j", and ambient

field (external flow) conditions by subscript "a". The flow conditions at anyflow field point (x, r, ) are computed from the following equations, takenfrom Reference (3):

Momentum Transport:

22 1 2% 2) e -R /b1PU a a 2 (jj - aU) 1- e d (1)

Heat Transport:

OUH - 2 1T f( [1 _- 2ob d4 (2)

7

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Input

1. PRT T

2. Geometry

Subdivision

Repeatfor EachVolume Element

Aerdynamic Output

Calculation U,u',, T

Intensity CalculationSpectrum

Far Field [Shock Cell

SPL, Spectra I Noise

Per Element Calculation

Su,=2at ion

of ComponentSpectra

AtphericAbsor ptionCorections

1. SPL, Spectra2. PWL Spectrum3. OASPL, PNL Vs.6

Figure 3. Block Diagram of Jet Noise Aeroacoustic

Prediction Model.

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Shear Stresses:

2 22 ( 2 2 R O2 -R 2/b 2

TX 2.- U ) - e 0 b d1 (3)

P 2 r J 'a1 b 2m

Tr ~ J 2 2 -R- ~ R /bT_~ Cm U 2 f2 Tef F R o e o

= (Uj.- U a ) - erf ( - e

x cos DdD (4)

2 2

T_ Cm (1 2U - U ) erf -) e -R,/b ]

x sin DdD (5)

wherefdenotes a contour integral around the nozzle planform boundary.

In the above equations, U, p, and H are the mean velocity, density andenthalpy, respectively, and Tx, Tr and T4 are the x, r and 4 - components

of turbulent shear stress. The coordinates Ro and (P are defined by therelations

2 2

R 2 (r - v ) + 2rv [1 - cos(Q-a)]o 0o (6)

and R cosP = r-v cos(Q-)O o

The turbulent mixing length parameters bm Cmx and bh = Chx are determinedby the momentum spreading rate parameter Cm and enthalpy spreading para-meter Ch. Empirical expressions for these have been developed in Reference(3), and are as follows:

C = 0,075 Ch = 1.15C (7)m (i + CIVR) (1 + C 2 M 1 ) h m

9

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where VR = Ua/U. and Mj = U./Ci, the jet exit Mach number. The constantsC1 and C2 were etermined from calibrations with conical nozzle flow fieldvelocity measurements, and values of C1 = 0.25 and C2 = 0.08 were found togive the best agreement with experiments.

The velocity and density are determined from the distributions of(pU2 ) and (pUH) from the following expressions:

U =pUH LOUH + Lp!a(OU2 )

2- + (2- + U (8)

where HU 2 _ C T2()pa

and Y - i p + _ (pU2) (10)

2

and 0 =u) T p(1)U2 pRg9

In the above expressions, C p and Rg are the specific heat at constantpressure and universal gas constant, respectively (Rg = yC p/(y-l)), y isthe ratio of specific heats, and p is the jet static pressure, assumed tobe equal to the ambient static pressure. The local temperature is T, andTa is the ambient static value.

The axial turbulence intensity u' is computed from the shear stresscomponents utilizing the following expression:

(u')' = ](Tr/p)2 + St (-o/p)' + at (10 'x/p)2 (12)

where 6t and Bt are empirically - determined constants.

Modifications to the above computation procedure are developed inReference (3) for nozzles with an axisymmetric centerbody or plug. Thismodification consists of a coordinate transformation of the variables (R0 ,D) as follows:

10

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R 2 = (Ar-Av) 2 + 2ArAv [l-cos(O-a)]0

R cost = Ar - Avo cos(-a) (13)

where Ar = - r2 (x) and A = 2 (o)b 0 -b

and rb(x) is the centerbody/plug contour coordinate specification. Forrb(x) = 0, Equation (13) reduce to Equation (6).

Equations (1) through (13) completely define the flow field calculationprocedure. As discussed in the previous section, the flow properties areevaluated at all field points corresponding to eddy volume element centers(x,r ,4)

3.3 TURBULENT MIXING NOISE PREDICTION

Expressions are developed in Reference (3), for the far-field noise ofconvected quadrupoles imbedded in a parallel shear flow, utilizing high-frequency asymptotic solutions to Lilley's equation. These expressions,for a source of unit volume and unit strength, when applied to a collectionof sources distributed throughout a parallel shear flow model of the jetplume, yield the following equation for the far-field noise spectrum:

p2 (a (a + 4a + 2 a + 2a )dy (14)p(,,) = aax xy yy yz

y

where f ( )d; implies integration over the entire jet plume. The factorsaxx, axy, ayy and ayz are the directivity factors for each of the contri-buting quadrupole types contained in each turbulent eddy volume element.The factor a is given by

= () 1Pa 2 2 Ca \2 (l- co8 2 -2--y7-(1-M cos) -(l-M cose) (15)16r R Ca 0O

where 1(2) is given by

1 2 (u,)7 T ) 4 ex p ( 2] (16)I( ) = (u -) (QTo) e1p

0 L

and To is the two-point velocity correlation characteristic time delay.

ii

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Subscript "o" refers to the volume-element or eddy-center location conditions.The parameters M o and Mc are defined as

M =U /C M =U /Co 0 a c c a

where Uc is the effective convection velocity of the eddy.

The directivity factors axx, axy, ayy and a have different forms,depending on the location of the source and the velocity and temperatureprofiles in the vicinity of the source. As discussed in Reference (3), thesefactors depend explicitly upon a shielding function g2, which has the form

2 2 2g2(r)= (l-M cos0) (Ca/C) Cos a (17)(l-M cose) 2

where C=C(r) and M=M(r)/Ca. Given a velocity U(r) and temperature profilesC(r) - Tr), the shielding function profile can be computed per Equation(17). Deyending on the observer angle 6 and the profile shapes, the pro-file of g (r) may have both positive and negative "zones", or may be posi-tive for all values of r. If a negative region exists, then the possibilityof fluid shielding of the sound scrce exists, depending on the location ofthe sou ce relative to the negative or shielding zone. The location r=rowhere g (r) crosses zero is termed a turning point; practically speaking,more than one turning point can occur, although more than two turningpoints is very rare.

A maximum of two turning points is considered herein. This allows sixpossible situations regarding the source location relative to a shieldingzone. These are illustrated qualitatively in Figure 4. This figure showsg2 (r) plotted versus radial distance in the jet plume for six cases. Incase (a), g2 (r) is positive for all values of r, so no shielding of thesource occurs no matter where it is located radially in the jet. In case(b), the source is located outboard of the region where g2 (r) is negative,so still no shielding occurs. In case (c), however, the source is locatedinboard of the turning point, ro < ral, and lies inside the shielding zone.The source will therefore be shielded to some extent.

In cases (d,e,f) shown in Figure 4, there are two turning points r I

and ra2 > ral. In case (d), the source lies outside of both turning pointsand therefore sees no shielding. In case (e), the source lies between thetwo turning points and thus is shielded by the fluid layer between r=ro andr=ra 2.

12

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No Turning Points One Turning Point One Turning Point

r r0 r <r

O ro

g 2

0-

t I I_ .rr 1 r

rr o ra 1

0 al0 04 Two Turning Points Two Turning Points Two Turning Points

r> r, r 2 r G <r 0 <r r 0 r 0 r0g r r rgo o

1 r 1 r r I 1 r 1a1 ra2 r 1 r 2 r 1 ro2

Dimensionless Radial Coordinate r/a

Figure 4. Possible Solution Types for a Maximum of Two Turning

Points. Shaded Areas Denote Shielding of Source.

13

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IThe acoustic radiation solutions for all of the six cases illustrated in

Figure 4 are worked out in detail in References (3), and yield different formsfor the directivity factors axx, axy, ayy and ayz for each case. Thesedirectivity factors have the following forms:

cos4e

a Co 0 (18a)xx (1-M coso) 4 xx

C

2 2

a - g 0CosO (18b)xy 2(1-M cose) 2 xy

3 4ayy = ' go Byy (18c)

1 4a - 4 (18d)ayz =8 go yz

2 2

where go is the value of g (r) at the source radius r=ro . The shieldingcoefficients Bxx, Bxy, Byy and Byz depend upon the case encountered inFigure 4. If the parameters a01 , B02 and B12 are defined as

r I

B01 = exp J-2k f g2 (r) I/2 dr I (19a)

r0

r0

02 = exp -2k f Ig2 (r)il 2 dr (19b)

ro

B12 = exp 2k J g2 (r)j1 /2 dr (19c)

ral

where k=O/Ca, the shielding coefficients are then determined from thefollowing table:

14

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Table 1. Shielding Coefficients .

Case xx 6xy Byy yz

b 1 1 1 1

C 01 0 0 0

d 1 1 1 1

e 02 0 0 0

f 12 a12 62 2

Note that a value of xx, etc., of unity indicates no fluid shielding, as incases (a), (b) and (d). When the source is imbedded within the shieldingzone, as in cases (c) and (e), only the x-x quadrupole contributes, forreasons explained in Reference (3).

3.4 SHOCK-CELL NOISE PREDICTION

As discussed in Section 3.1, the shock cell broadband noise pre-diction is based on a modification of the theory of Harper-Bourne andFisher (14). A thorough discussion of this theory and its application tononcircular nozzles can be found in Reference (3).

Although the analysis of Reference (3) demonstrated that noncircularnozzle shock-cell noise exhibits the same scaling of noise level withoperating conditions as that for a conical nozzle, the influence of nozzleshape on noise level and spectrum shape was not quantified to the extentthat a verified prediction method could be established. A method forpredicting the shock cell structures (number of cells, spacing, etc.) isstill required before a general shock noise prediction procedure can beestablished. An interim shock cell noise prediction method was thereforeadopted for incorporation into the unified aeroacoustic prediction model,with the expectation of replacement by a more general method at some futuredate.

The interim method is essentially that of Deneuville (16), with somemodifications to simplify the calculation and incorporate some of the ideasdeveloped in Reference (3). The method consists of modeling the shock cellnoise component of the spectrum by two straight lines, as illustrated inFigure 5. The primary variables required are peak sound pressure levelSPLp and the frequency fp at which this occurs.

15

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I(a)

Typical MeasuredSpectrum in For-;7- Shock Noise

ward Quadrant

0 X Mixing- / Shock Noise \<Noise

Frequency, KHz

(b)

SPLp

21 dB per /I 3dBper

fP

Figure 5. Empirical Model of Shock Cell NoiseComponent of Spectrum: (a) ShockCell Component Approximated byStraight Lines; (b) Model Represent-

ation of Shock Cell Spectrum and

Correlation Parameters.

16

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Given a nozzle operating at pressure ratio PR, jet velocity Vj,

having total flow area A, equivalent diameter D e = 4-Aj/, and hydraulic

diameter Dh = 4Aj/Pw (where Pw is the nozzle bounaary wetted perimeter),the parameters SPLp and fp can be computed as a function of observer angleOi . The computation proceeds as follows:

(1) compute shock strength parameter B from

= 4M 2 - 1 (20)J

where M 2 PR -(21)

(2) compute average shock-cell spacing L fromavg

L = 1.1 D (22)avg eq

(3) Compute peak noise frequency from

C ( + M cos e.)- (23)

P L c iavg

where U = 0.7 U. and M U/C a *c j c ca

(4) Compute peak SPL from

SPL p(6) = 152.6 + 40 log 1 0 (B) + 10 log 10 (Aj/R 2)

+ 10 log1 0 (Dh/Deq)-40 log 10 (l-Macosei) (24)

+ 10 log1 0 (N/8)

where Ma = Ua/Ca , the flight Mach number, and N is the number of shock

cells (usually N = 8 is assumed). The spectrum shape is then calculatedfrom the assumed two straight-line model shown in Figure 5. The equationsare as follows:

SPL(f,e i) = SPL (ei) - 10 lOgl0(f/fp), f > fpo p(25)

SPL(f,e i) = SPL (eO) + 70 log 10 (f/fp ), f < f1 ' p

17

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Equations (20 through 25) completely describe the shock cell noise predic-

tion method for obtaining 1/3-octave spectra at any observer angle ei.

3.5 AEROACOUSTIC MODEL INTEGRATION

An outline of the basic prediction method and a description of thecomponent building blocks have been presented in the preceding sections.This section describes how these building blocks are tied together. Addi-tionally, some practical guidelines are given which were found from exper-ience to be helpful in producing reasonably accurate predictions whilemaximizing computational efficiency.

The mixing noise spectrum is computed from equation (14), with theintegration over the jet plume J ( ) d7 replaced (or approximated) by asummation over all eddy-volume elements. Since equation (14) representsthe narrowband spectrum in terms of source frequency Q (emitted frequencyin a reference frame moving with the eddy), a conversion is made to 1/3-octave spectrum based on observed center frequency f. It is assumed thatthe 1/3-octave band level can be approximated by the narrowband levelevaluated at the center frequency, multiplied by the bandwidth, rather thanintegrating the narrowband level distribution over the bandwidth. Thestandard 1/3-octave center frequencies are used. For each eddy-volumeelement, at each observer angle 8i = 1800 - 6, the source frequency iscalculated for each 1/3-octave center frequency from the relation

= 27f(l-M c cos 6) (26)

The spectrum shape of a given eddy, equation (16), determines the amountcontributed by a given eddy at that 1/3-octave frequency. Theoretically,all eddies contribute some amount at all 1/3-octave frequencies, but therather "peaky" nature of I(Q) given by equation (16) dictates that themajor contribution of an eddy will be in the vicinity of 0 - 4/T0 .

Computationally, the integrand of equation (14) can be expressedexplicitly in terms of observed frequency, since the source frequencyalways occurs in the combination Q/(l-MccosO). The one exception is in theexponent of the spectrum function I(R), equation (16). For example, theproduct aaxx can be rewritten as

axx Pa 2(u')7(2fTo) 4xcos 46 (Ca/Co)2 (To)216 2R2 C a (I-M cose) 2 (l-M cos6) 2 8 I

a o c

Similar expressions can be derived for aaxy, etc.

18

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The eddy convection factor (l-MccosO) has a singularity at M cosa 1.To circumvent this computational difficulty, it is replaced by a modified con-vection factor as suggested by Ffowcs-Williams (6) and Ribner (8), as follows:

C = l-McCosa (l-McCosa) 2 + (atu'/Ca)2 (27)

where, as Ffowcs-Williams and Ribner have shown, the term (atu'/ca) accountsfor the finite life-time of the eddy as it is convected downstream. Theconstant at was determined (from comparison of prediction with experiments)to be approximately 0.5, independent of source location, jet operating con-ditions and nozzle geometry. An additional assumption was made that the flowconvection factor (l-Mocose) can be replaced by the modified eddy convectionfactor C given by equation (27).

The eddy convection Mach number must be a function of the local flowMach number of the eddy-volume being considered. Several expressions for Mcwere tried; the best results (over a wide range of nozzle operating condi-tions and geometries) were obtained with the following:

mc = 2 (M + 0.65 M.) (28)

where Mj = Uj/Ca, the nozzle exit acoustic Mach number. Equation (28) repre-sents a simple average of the classical assumption Mc = 0.65 Mj and the localMach number Mo = M(ro). For suppressor nozzles, equation (28) works best ifM is replaced by the postmerged potential core Mach number Mm = Um/Ca.

is can be evaluated from the results of the flow field calculation des-cribed in Section 3.2.

The acoustic theory summarized in Section 3.3 applies only for axi-symmetric jets. For nonaxisymmetric nozzles (multilobe, chute, tube, etc.),an assumption is therefore made that a representative average radial profileat each axial station can be derived which, when inserted in the acousticcalculation, will adequately model the acoustic characteristics of the asym-metric jet. The mass-averaged values of U and p are calculated from theazimuthal average of the quantities pU2 and pUH. The resulting distributionsof U(x,r) and p(x,r) are then employed in the acoustic calculation describedin Section 3.3.

For axisymmetric jets, the empirical similarity relation (to - (aU/;r) - 1

derived by Davies et al.(13) can be used to calculate the local value of Tofrom the radial velocity profiles U(r). For a multichute or lobe nozzle,however, there are volume elements close to the nozzle exit plane whichhave negligible radial gradients DU/ar but large azimuthal gradients aU/Do.It is therefore assumed that To is a function of both 3U/r and aU/ao. FromReichardt's hypothesis (see Reference 3), the transverse shear stresses arerelated to aU/;r and ;U/I by the approximate formulae

19

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V

Tr X and _A 'U_

P Dr p r a

where C m x/2. Thus the transverse derivatives of U can be expressed interms of Tr and To as follows:

U . (Tr/P) and 1 3U3r U CT x r a U _C7 x

m m

A new transverse derivative aU/in is therefore defined in terms of the abover and derivatives as follows,

n - U C2 Tr4 + tV) (29)

m

such that

To -- (JO3n (30)

The parameter Ut is an empirical constant which must be evaluated from com-parison with experiments.

For prediction of jet noise in flight, the mean square sound pressure -

level should be multiplied by the dynamic amplification factor (I + Macose)where Ma = Ua/Ca. In addition, the convection and flow Mach numbers arereplaced by (Mc-Ma) and (Mo-Ma), respectively, where Mc and M o are evaluatedin a reference frame fixed to the nozzle.

Finally, in all predictions of 1/3-octave spectra, the atmospheric

attenuation corrections given by Reference (15) are applied, using standard-day corrections (70% relative humidity and 590 F dry-bulb temperature)evaluated at the center frequency.

20

~ii*°

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4.0 COMPUTER PROGRAM DESCRIPTION

4.1 INTRODUCTION

The central theme of this report has been the development of a generalmethod for predicting the acroacoustic characteristics of turbulent jets for

a wide range of nozzle flow conditions and nozzle geometries. The precedingsection describes the analytic, algebraic relationships which have been

developed to represent the various physical aspects of the mathematicalmodel. The purpose of this section is to describe the computational algo-

rithms and associated computer program which provides the necessary link

between the symbolic representation of the model and the actual numericalresults of the prediction method.

The computer program is written in FORTRAN IV language. It has been run

on both the GE/Honeywell 6080 and CDC 7600 computers, and can easily be modi-fied for running on other systems. The program subdivides the jet plumeutilizing a built-in grid system which requires minimal input for specifi-cation. This grid system can be superseded by the user through more complex

input if desired. The nozzle geometry is input through discrete point coor-

dinates for each nozzle element boundary, and up to 109 elements can be inputfor a given case. A maximum of 24 axial stations along the jet plume is

permitted, and up to 200 radial points per axial station can be accommodated.These limits can be changed if so desired by modifying the appropriate

DIMENSION and COMMON statements in the program logic.

The limiting assumptions made in developing the method have been dis-cussed in Section 3.0, but it is appropriate to summarize them here to warnagainst indiscriminate violation of these limitations. They are as follows:

1. The exhaust nozzle elements should be co-planar, i.e., each tube orchute of a multielement configuration should exhaust at the same axial

plane. However, nozzle element exit planes can be staggered, providedthat the mixing layer of a given element does not impinge on the wall

of another element.

2. The jet exhaust gases must all be of the same constituent, because

the calculation cannot accommodate gas mixtures or species concen-t rations.

3. Within any nozzle element, the flow is assumed to be uniform at the

exit plane.

4. The time-averaged static pressure is assumed to be constant and

uniform throughout the jet flow field and surrounding ambientfield.

5. The exhaust nozzle elements must discharge axially, radial meanflow and swirl are neglected in the model.

21

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6. The effects of shock formations on mixing and turbulence levels areneglected.

These assumptions and limitations are those which pertain to the typesof problems which can be analyzed. There are, of course, additional assump-tions which went into the formulation of the model itself which may restrictthe accuracy of the model, but not the type of problem which can be analyzed.The user is advised to consult Reference (3) for the details of the modelformulation.

4.2 PROGRAM NOMENCLATURE AND SYMBOL CONVENTION

The jet plume and nozzle geometry coordinates are computed in the MAINroutine. The jet plume is divided into KX axial slices, specified by KA(l < KA < KX). The FORTRAN symbol variables for the various coordinateparameters and indices are shown in Figure 6. Note that the radial sub-division, specified by index M (1 < M < NR), proceeds in increments DSIG(KA),from SIG = RMIN(KA) to the maximum value set by NR. The value of NR isdetermined during the calculation from the location where the axial momentumflux is within a certain tolerance of being equal to the ambient level, i.e.,

IRU2 - RU2E(1)I < RU2M

where RU2M is a specified input tolerance. The maximum allowable value of NRcan be specified by the input variable IQUIT. The program dimension sizeslimit KX and IQUIT to the following maximum values:

KX < 24 IQUIT < 200

The nozzle geometry itself is input as a number (NEST) of boundary ele-ments. Each element is specified by coordinate pairs RA(I,J) and DALP(I,J),where RA(I,J) denotes the radius and DALP(I,J) denotes the angular increment,as shown in Figure 6. The index I denotes the boundary contour point number,and the index J denotes the boundary number. The reference angular location

for each boundary is given by ALPO(J). For each boundary, the exit-planevalues of total pressure PT(J) and total temperature TT(J) are alsospecified. Boundary number one (J=l) is always considered to be the ambientfield.

The far field acoustic calculations are performed on either a constant-radius arc or a sideline parallel to the jet axis, according to whether theinput variable NUMANG is set equal to 1 or 2, respectively. For NUMANG = 1,the input DIST is the arc radius; for NUMANG = 2, DIST is the sideline dis-tance. The acoustic arena geometry specification in terms of FORTRAN vari-ables is shown in Figure 7. Note that a distinction is made between thesource-to-observer distance RSTAR and the nozzle-to-observer distance RADIUS.The observer angle relative to the jet axis THETA is always in units ofradians, while the observer angle relative to the inlet axis THETD is inunits of degrees. The far-field sound pressure level SPL(I,J) is computed at

22

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RA (7, 2)

DALP (7, 2)

8 790

0005 ALPO (2)

12 00 30

(b) Nozzle Exit Plane Example NozzleElement Coordinates

S IG

DX

KAl 21 3 5 6 KX-l KX

D SIG

RMIN

-n.X

X

(a) Radial/Axial Plane

Figure 6. FORTRAN Symbol Convention for Coordinates andGeometric Variables.

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Observer

161 Q )DIST

________L___I Jet Axis

xSource

Figure 7. FORTRAN Symbol Convention for Acoustic Arena Variables.

24

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_i _ -. . ... .. ...-. --

every 1/3-octave frequency from FMIN to FMAX, at ten-degree increments from

THETD = 200 to 160'.

A list of the important FORTRAN symbols used in the computer program is

given in Table 2, along with their algebraic equivalents where possible. A

corplete description of all of the input variables and examples of input

preparation are given in Appendix A.

4.3 DESCRIPTION OF PROGRAM AND SUBROUTINES

A flow chart of the computer program logic is shown in Figure 8. It

indicates the sequence of operations, the interconnections of various portionsof the program, and their functions. A description of the main program and

each of the subroutines is given in the following paragraphs.

4.3.1 MAIN

The main program initiates the computation and controls the sequence of

operations. It reads the input data, computes the grid system for the aero-

dynamic flow field, and computes the various required nozzle exit plane flow

parameters such as velocities, Mach numbers, momentum and enthalpy fluxes,etc. The main program prints out all input data, nozzle exit conditions,

nozzle geometry, and coordinate system parameters.

The main program controls and executes the jet plume flow field compu-

tation. After each axial slice has been evaluated, the MAIN program calls

subroutine SLICE to perform the requested acoustic calculations. Upon com-

pleting the calculations at all axial slices, MAIN then calls OUTPUT to per-

form some final calculations and print out the far-field noise levels. If

additional cases are requested, the entire procedure is repeated, beginningwith reading of input data; otherwise the execution is halted.

4.3.2 ARCCOS(X)

This is a function subroutine which computes the principal value of the

arc cosine of the variable X. It is used in MAIN in evaluating certain

angles relating boundary coordinate points and flow field location points.

4.3.3 ERF(X)

This function sibroutine evaluates the error function of argument X

using polynomial approximations as given in Reference (19). It is used in

MAIN for evaluating flow field integrands.

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Table 2. List of FORTRAN Symbols.

FORTRANSymbol Meaning Related Subroutines

AA Air attenuation factor ATMOSAAA Intermediate variable LSPFIT, MAIN

ABDTH IAII MAINABLE Intermediate variable MAINABPA k -al MAINACH Mach number M MAINACHM Average mach number MAINACH2 M2 MAINAK Sound level constant MAIN, OUTPUTAL Lighthill parameter MAINALFA Frequency constant MA'NALP Angle MAINALPHT Convection constant at SLICEALPO Reference boundary angle MAINAMUIN Input turbulence constant pt MAINAMULT Intermediate value for lit MAINAO Speed of sound Ca MAINATOTAL Total flow area MAINB Intermediate variable LSPFITBETA Shock strength parameter B SHOCKBETAIN Input turbulence constant 6t MAINBETAMC Convection constant Mc MAIN, SLICEBK Intermediate variable SLICEBKR Intermediate variable MAINBOT Intermediate variable LSPFITBUG Intermediate variable MAIN

C Constant LSPFITCH Spreading parameter Ch/Cm MAINCHX Spreading parameter Chx MAINCJOCO Ratio of Cj/Ca SLICECM Spreading parameter Cm MAINCMAX Intermediate variable TPNLCCMC Intermediate variable MAINCMMC Spreading constant C1 MAINCMVR Spreading constant C2 MAINCNST Constant SLICECO Ambient speed of sound Ca MAIN, SLICE, SHOCKCOEF Conversion factor OUTPUTCONV Conxection factor SHOCKCONVF Flight dynamic factor SLICECONVO Convection factor SLICECONV2 Modified convection factor C SLICECON1 Constant SLICE

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Table 2. List of FORTRAN Symbols (Continued).

FORTRAN

Symbol Meaning Related Subroutines

CON2 Constant SLICE

COST Cos P MAIN

COSTO Cos D MAINCP Specific heat Cp MAIN

CT Cos a SLICE, CRD

CTSQ Cos 2 a SLICE

CTH Cos e SHOCK

CVR Intermediate variable MAIN

DALP Boundary coordinate Aa MAIN

DDTHE Tolerance on A6, radians SLICE

DDTHED Tolerance on AO, degrees SLICE

DELRA Transformed boundary radius Av MAIN

DELSIG Transformed radius Ar MAIN

DELTA Turbulence constant 6 t MAIN

DELTIN Input array of 6t MAIN

DEQ Equivalent diameter Deq MAIN, SLICE, SHOCK

DIA Reference Dea MAIN

DIRECT Directivity factor SLICE

DIST Sideline or arc distance MAIN, SLICE

DJET Reference diameter MAIN

DPHI Ai MAIN

DRMIN Ar - minimum value SLICE

DS Source strength amplitude SLICE

DSIG Ar MAIN, SLICE

DSPL Mixing noise pressure SLICE, OUTPUT

DSPL1 Intermediate variable SHOCK

DSPL2 Intermediate variable SHOCK

DTHED AO, degrees SLICE

DTHM Maximum increment of i MAIN

DU Intermediate variable MAIN

DUDR 3U/3r MAIN, SLICE

DV Eddy volume dV SLICE

DX Axial step size Ax MAIN, SLICEEF Enthalpy flux MAIN

EFE Enthalpy flux MAIN

EM Mach number SLICE

EMACH Exit Mach number MAIN, SLICE, OUTPUT

F Intermediate variable LSPFIT

FAC Intermediate variable PNLC

FC Center frequency SLICE

FIRSTU Flight velocity Ua MAIN, SLICE

FIS Intermediate variable MAIN

FM Mass flow MAIN

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. ... ..

Table 2. List of FORTRAN Symbols (Continued).

FORTRANSymbol Meaning Related Subroutines

FMAX Maximum obs2rved frequency MAIN, OUTPUTFMIN Minimum observed frequency MAIN, OUTPUTFO Observed frequency SLICE, SHOCK, OUTPUTFP Peak frequency SHOCKFR Frequency ratio SLICEFRSQ Intermediate variable SLICEFS Source frequency SLICEGAM Specific heat ratio y MAIN, SHOCKGAMA Gas constant parameter MAIN

GEXP Gas constant parameter SHOCKGM Shielding function CRDGOSQ Shielding function CRDG2 Shielding function SLICE, CRDHF Spectrum function SLICEHPSI Intermediate variable MAINHTR Stagnation enthalpy MAINI Index ALLIC Index LSPFITIDENT Title (80-characters) MAINII Index TPNLCIMH Index MAINIQUIT Maximum number of points MAINIS Index MAINISSY Index MAINISAVE Index LSPFITISYM Symmetry indicator MAINIT Symmetry indicator MAINJ Index ALLTMAX Maximum band number OUTPUT, SHOCK, SLICE

JMIN Minimum band number OUTPUT, SHOCK, SLICEJl Index CRDJll Index CRDJ2 Index CRDJ21 Index CRDj211 Index CRDK Index, also wave number MAIN, SLICE, PNLCKN Surrounding boundary index MAINKNCAS Case counter MAINKNK Surrounding boundary index MAINKX Number of axial slices MAIN

L Index MAINLAVG Shock spacing SHOCKLEAF Number of boundary leaves MAIN

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Table 2. List of FORTRAN Symbols (Continued).

FORTRANSymbol Meaning Related Subroutines

LEAV Number of boundary leaves MAINLINE Printout counter MAINLPHI Number of flow field leaves MAINLQ Index MAINM Index MAIN, SLICEMACH Mach number SLICEMAXNOY Maximum noy value PNLCMC Convection Mach number SLICE, SHOCK, CRDMCIN Input array of Mc SLICEMIN Input array of Mo CRDMJ Jet exit Mach number SHOCKN Index, also number of shocks MAIN, SHOCK, LSPFITNBREF Reference boundary number MAINNCASE Number of cases MAINNCBDY Number of centerbody points MAINNCELL Number of shock cells MAIN, SHOCKNCOUNT Counter LSPFITNN Acoustic calculation selector MAIN, SLICE

NODE Intermediate variable MAINNOV Minimum number of points MAINNOY Noy value PNLCNPAGE Page counter MAINNPR Printout counter MAINNPRINT Printout selector MAIN, SLICENPTS Number of points LSPFITNR Number of points SLICE, CRDNRI Index SLICENTP Number of turning points SLICE, CRDNUM Number of boundary points MAINNUMANG Arena selector MAIN, SLICENUMK Number of boundary points MAINNXC Index LSPFITOAPWL Overall power level OUTPUTOASPL Overall sound pressure level OUTPUT, PNLCOBSTN Observed Strouhal number OUTPUTOMEGR Source radian frequency SLICEPAA Ambient static pressure MAINPC Intermediate variable PNLCPGC Gas constant parameter MAINPHI Angle MAINP1 Constant 7 MAIN, SLICE, OUTPUTPI02 1/2 CRD

P12 271 MAIN

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Table 2. List of FORTRAN Symbols (Continued).

FORTRANSymbol Meaning Related Subroutines

PNDB PNdB PNLCPNL PNL OUTPUT, PNLCPNLT PNLt, tone-corrected PNL OUTPUTPOWER Exponent MAINPS Ambient static pressure MAIN, SHOCKPSQ Square of acoustic pressure OUTPUTPSQM Mixing noise__22 SHOCKPSQS Shock noise p SHOCKPSQT Total noise p7 SHOCKPT Stagnation pressure MAIN, SHOCKPWL Power level OUTPUTPWR Sound power, watts OUTPUTQ Intermediate variable MAINRA Boundary coordinate radius MAINRAD Flow integration variable Ro MAINRADO Flow integration variable Ro MAINRADIUS Nozzle-to-observer radius R SLICE, OUTPUT, ATMOSRADX Argument Ro/Cmx MAINRCBDY Centerbody radial cooordinate MAINPRCRIT Critical pressure ratio SHOCKRCRC Intermediate variable MAINRFO Intermediate variable OUTPUTRHO Density p MAINRHOE Ambient density Pa MAIN, SLICERHOESQ p2 SLICEaRHOR Azimuthally-averaged p MAIN, SLICERIN Input radius SLICE, CRDRJET Reference jet density ratio MAINRMIN Minimum value of r MAINRMINEX Exit plane value of RMIN MAINRMINSQ Square of RMIN MAINRMNSQE Square of RMINEX MAINRMP Dummy variable MAINRND Normalized radius r/Deq MAINROOT Root (zero) of g2 SLICEROOT2 r2_ SLICERO Source radius ro CRDRSIG Turning point radius ra SLICE, CRDRSIGI ral CRDRSIG2 r.2 CRDRSORSQ Source location correction (R*/R)2 SLICERSTAR Source-to-observer radius R* SLICE

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Table 2. List of FORTRAN Symbols (Continued).

FORTRANSymbol Meaning Related Subroutines

RU Mass flux pU MAINRU2 Momentum flux pU2 MAINRU2E Exit plane value of pU2 MAINRU2M Minimum value of pU2 MAINRU2REF Reference value of pU2 MAINR1 Intermediate variable CRDR2 Intermediate variable CRDS Intermediate variable TPNLCSA Intermediate variable MAINSAC Intermediate value of T MAINSACO Intermediate value of To MAINSAR Intermediate value of Tr MAINSARO Intermediate value of Tr MAINSAX Intermediate value of Tx MAINSAXO Intermediate value of Tx MAIN

SBAR Intermediate variable TPNLCSDU Intermediate value of 3U/Dr MAINSEFE Integral of enthalpy flux MAINSGN Sign LSPFITSGNI Sign CRDSGN2 Sign CRDSGI Intermediate variable CRDSG2 Intermediate variable CRDSHIELD Shielding integral SLICE, CRDSIC Intermediate value of T MAINSIG Radius r MAINSIGN Sign ERFSIGSQ r2 MAINSIGR Radius r MAIN, SLICESINT Sin 0 MAINSINTO Sin e, MAINSIR Intermediate value of Tr MAINSIX Intermediate value of Tx MAINSPL SPL array ALLSPLL Intermediate variable TPNLCSPLMAX Maximum SPL SHOCKSPLP Intermediate variable TPNLCSPLPP Intermediate variable TPNLCSPLU Intermediate variable TPNLCSRU Mass flux integral MAIN

SRUM Mass flux integral MAINSRU2 Momentum flux integral MAINSRU2M Momentum flux integral MAIN

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Table 2. List of FORTRAN Symbols (Continued).

FORTRANSymbol Meaning Related Subroutines

SS SPL array PNLCSSPL Shock noise SPL array SHOCKSTC Azimuthal shear stress T MAINSTR Radial shear stress Tr MAINSTRFR Radial coordinate stretching factor MAINSTRFX Axial coordinate stretching factor MAINSTX Axial shear stress Tx MAINSUE Reference velocity MAINSUM Sum OUTPUTSUMNOY Sum of noy value PNLCSUMSPL Sum of SPL PNLCSUM1 Sum CRDSUM2 Sum CRDSU8 Integral of source strength MAINSU8M Integral of source strength MAINSV2 Square of velocity MAINSl Intermediate variable LSPFITT Temperature ERF, MAINTA Intermediate variable MAINTAA Ambient static temperature MAINTAO Intermediate variable MAINTAU Total shear stress T MAINTAUR Azimuthal average of T MAIN, SLICETC2 Intermediate variable TPNLCTC3 Intermediate variable TPNLCTE Exit static temperature MAINTEMP Normalized temperature T/Ta SLICETERM Directivity factor SLICETH Angle MAINTHCR Critical angle ecr SHOCKTERM Directivity factor SLICETHE Angle 0 SLICE, CRDTHETA Observer angle 0, radians SLICE, OUTPUTTHETD Observer angle el, degrees SLICE, OUTPUT, SHOCK

THO 00 MAINTHT Observer angle 01, radians SHOCKTI Intermediate value of enthalpy flux MAINTOP Intermediate variable LSPFITTSR Static temperature MAINTSTD Circumferential asymmetry test parameter MAINTSTH Circumferential asymmetry test parameter MAINTSTHL Circumferential asymmetry test parameter MAINTSTL Circumferential asymmetry test parameter MAIN

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Table 2. List of FORTRAN Symbols (Concluded).

FORTRANSymbol Meaning Related Subroutines

TT Stagnation temperature MAINTTR Stagnation temperature MAINTURBIN Turbulence intensity, u' MAINU Mean velocity MAINUAP Intermediate variable MAINUAVG Mass-average of U at x MAINUC Convection velocity Uc SHOCKUE Exit plane velocity Uj MAIN, SHOCKUGLY Intermediate variable MAINUJET Reference exit velocity MAINUMAX Maximum local value of U at x MAINUND Normalized value of U, U/UREF MAINUNITS Constant for units conversion MAIN, OUTPUTUR Azimuthal average of U MAIN, SLICEUREF Reference exit velocity MAINU8 Intermediate value of source strength MAINU81 Integral of source strength MAINVA Intermediate value of momentum MAINVAO Intermediate value of momentum MAINVI Intermediate value of momentum MAINVMAX Maximum of velocities inside and outside MAINVMIN Minimum of velocities inside and outside MAINVO Flight velocity Ua SHOCKVR Velocity ratio VMIN/VMAX MAINWITHIN Dummy variable LSPFITX Axial distance x MAIN, SLICEXCBDY Centerbody axial coordinate MAINXD Intermediate variable LSPFITXE Exit plane axial coordinate MAINXND Normalized axial coordinate X/Deq MAINXOR Variable x/R SLICEXl Intermediate variable for curve fitting LSPFITX13 Intermediate variable for curve fitting LSPFITX4 Intermediate variable for curve fitting LSPFITX43 Intermediate variable for curve fitting LSPFITY Intermediate variable for curve fitting LSPFITYC Intermediate variable for curve fitting LSPFITYI Intermediate variable for curve fitting LSPFITY3 Intermediate variable for curve fitting LSPFIT

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St ti oil

Pint Out, Radfialanld Az i 11111a I

si s i t)( I o ils

Of Flo"

II. id Input

PrIq I It Oilt S I icAvc 1-,

C o li i I N1N1P lI ali I ' Y is

mI lilt N'\ Ii

Sit.ion

Flo~

al

CA I ic

cul ai it ill Y

YeNsI Ye

Fiont 8. CotIe Prora Flo Chart

From E~34

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TStart 4

First NoInelice~

YesCompute Jet

Compute Arena tGeomutry arn Plume Shielding

Geometry andandSet SPL = 0 I'an

Ie ST=0Turning

Points

ComputeAzimuthallyAveraged Norm-alized Radial

Profiles

Compute RadialSource Strength Calculate Eddyand Frequency Mixing NoiseDistributions Spectrum

Sum S ectra-]low No

rintout

No as-

Yes aluer

Print OutRadial

Profiles Vlu

Yes

4

(b) Subroutine SLICE

Figure 8. Computer Program Flowchart (Continued).

35

MEN wbddw

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S rI

Band spt i-Ira to1/3 Getavc SPil

Call SiloK

Cal]( n ] utc.Pld SIXCct it1ia

P~int OuterP

al PLpcr

CN.and TPNLT

C) lult e OUTPU

Figure 8. C or Prora A l owat(ocue)

Yes

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4.3.4 LSPFIT

Subroutine LSPFIT is a curve-fitting routine which utilizes least-squares polynomial fits of second order to perform interpolation, differentia-tion and integration of input discrete-point data. The calling statement is:

CALL LSPFIT(X, Y, N, XC, YC, NC, NF, A)

where (X, Y) are the input data coordinates (N values of each), XC are thevalues of X where output is requested, YC are the output functions, NC is thenumber of output data points, and NF indicates the type of output desired.The coding for NF is as follows:

NF = 0, YC are interpolated values of Y

NF = 1, YC are derivatives of Y

NF = -1, YC is the integral of Y fromXC(l) to XC(J), 1 < J < NC.

The parameter A is the second derivative of Y. Subroutine LSPFIT is used inMAIN to interpolate input plug/centerbody geometry coordinates at variousaxial stations in the flow field, and to obtain radial gradients of densityfrom the computed density profiles.

4.3.5 SLICE

Subroutine SLICE directs the mixing noise calculation for each axialslice. The calling sequence is as follows:

CALL SLICE (X(KA), DSIG(KA), DX, M)

where X(KA) is the axial location, DSIG(KA) is the radial step size, DX isthe axial slice thickness, and M is the number of radial points in the slice.The flow parameters (which are circumferentially mass-averaged values) aretransferred through labeled COMMON statements. Subroutine SLICE computes theacoustic arena geometry parameters THETA, THETD, RADIUS and initializes SPL(I,J) to zero during the first call, skipping this calculation on succeedingcalls. The normalized radial profiles of velocity (MACH) and temperature(TEMP) are evaluated, followed by a calculation of source strength amplitudeDS and characteristic frequency FS for each radial volume element.

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Subroutine SLICE compute-s the acoustic shielding function profiles G2(J),the number of turning points NTP, and their locations RSIG. Subroutine CRDis then called to calculate the acoustic shielding exponentials and quadrupoledirectivity functions. Subroutine SLICE then sums up the mixing noise con-tributions from each radial volume element, factoring in their individualsource strengths, characteristic frequencies, spectrum shapes, directivities,and shielding factors. The resulting noise spectra from each slice is storedas the variable DSPL(I,J), where I denotes the observer angle index and J isthe 1/3-octave frequency band index. Upon completing the calculation for agiven slice, SLICE returns control to MAiN.

4.1.6 CRD

Subroutine CRD computes the Jhiiilding fiinction integrals and quadrupoledirectivitv factors for a given axial slice as a function of radial sourcelocation. The radial distributions of normalized velocity (MACH) andtemperatures (TEMP) and shielding function (G2) are transferred to CRD throughlabeled CO DION statements. The calling statement is:

CALL, CR)

At each source radius, subroutine CRD interrogates the data to determinewhich of the six shielding conditions in Figure 4 applies, and computes theappropriate shielding integral (i.-O, 1,O2, or i12 ) , and the appropriatedirectivitv factors. After all radial source volumes have been evaluated,CRD returns control to SLICE.

4.3.7 OUTPUT

Subroutine OUTPUT performs the final acoustic calculations and printsout the far field SPL spectra, OASPL, PNL and PNLT directivities. The callingsequence is as follows:

CALL OUTPUT (ENACH, DJET, RJET, UJET, UNITS)

where EMACP, DJET, RJET, and UJET are the characteristic (usually reference)let Mali pamber, diameter, density ratio and velocity, respectively. Theparameter UNITS is a conversion factor for converting from lbf/ft 2 todynes/cmI relative to 0.0002 dvnes/cm2 . Subroutine OUTPUT converts thenarrow-hand spectra from SLICE into 1/3-octave levels. Subroutine SLICE thencalls SHOCK to compute SSPL spectra (shock noise) and adds these to theturbulent mixing noise spec tri to obtain the total noise spectra. The(orresponding power spectrum (PWL) is then computed, and subroutine ATMOS isthen called to correct all SPI spectra for atmospheric attenuation. Sub-routin,,s PNLC and TPNLC are then cal led to calculate perceived noise level

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- -_- -- --------

PNL and tone-corrected noise level PNLT. Finally, overall sound pressurelevel OASPL is computed, and all of these acoustic parameters are then

printed out. Subroutine OUTPUT then returns control to MAIN.

4.3.8 SHOCK

Subroutine SHOCK computes the broadband shock-associated noise spectraat each observer angle. The calling statement is as follows:

CALL SHOCK

All parameters are transferred into and out of this subroutine throughlabeled COMMON statements. Subroutine SHOCK computes the 1/3-octave SPLspectra for each nozzle boundary element which has a non-zero shock cellnumber input, NCELL > 0. The individual boundary contributions are summed ona mean-square pressure basis and added to the mixing noise spectra.

4.3.9 ATMOS

Subroutine ATMOS corrects the input SPL spectra for atmospheric attenu-ation effects using standard-day atmospheric absorption factors for 70%

relative humidity and 590 F ambient conditions. The calling sequence is asfollows:

CALL ATMOS (SPL, RADIUS)

where SPL(I,J) is the sound pressure spectrum array, I denotes the index for

observer angle, J denotes the index on frequency, and RADIUS(I) is thenozzle-to-observer distance array. The atmospheric absorption in dB per 1000ft from reference (15) is corrected to the proper distance RADIUS(J), and theresult is subtracted from SPL(I,J). The array of SPL(I,J) returned to OUTPUTis the corrected array.

4.3.10 PNLC

Subroutine PNLC computes the perceived noise level in PNdB at eachobserver angle from the input 1/3-octave spectra. The calling sequence is asfollows:

CALL PNLC (SS, FAC, PNDB, OASPL)

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where SS is the input array of either 1/3-octave or octave SPL values, FAC isa constant equal to 0.15 for 1/3-octave and 0.3 for octave levels, PNDB isthe output PNL, and OASPL is the conventional overall level. The method usedto calculate PNL is taken from reference (17). The OASPL output from sub-

routine PNLC is discarded because it only computes the summation for thefirst 24 values of SS. This is sometimes insufficient for model scale

conditions where the frequency range of interest can cover as many as 33 1/3-octave frequency bands.

4.3.11 TPNLC

Subroutine TPNLC determines a pure-tone correction factor to the PNLvalue as a function of the 1/3-octave SPL spectrum. The calling sequence is

as follows:

CALL TPNLC (SPL, PTCOR)

where SPL is the input 1/3-octave spectrum and PTCOR is the correction to beapplied to PNL to account for the presence of tones in the spectrum. Sub-routine TPNLC reads in SPL and returns PTCOR. The tone correction anddetection procedure is based on the method proposed in reference (18).

4.4 PROGRAM USAGE AND LOGIC

A complete description of the program input variables and input format

is given in Appendix A. A list of notes and suggestions on running theprogram is also included. A description of program output format, includingwarning flags and diagnostics, is given in Appendix B. A sample case listing

(including input data card images) is given in Appendix C for a 7-tube

suppressor nozzle, one of the data-theory comparison cases presented inReference (3). A complete FORTRAN source listing of the program logic isgiven in Appendix D.

Program users should be completely familiar with Appendix A, since there

are many pitfalls which can be avoided by giving attention to the recom-

mendations presented therein. The program flexibility permits analysis of

nozzle planforms of any imaginable shape, so long as certain input rules and

guidelines are followed. When non-axisymmetric nozzles are run, a completelythree-dimensional, turbulent, compressible flow field analysis is performed,

and input mistakes can be costly in terms of computer processor time. Theuser should make initial checkout runs for complex nozzles, running just one

or two axial slices at first, to ensure that all input is as desired, before

running a complete jet plume.

The program is designed to serve as a diagnostic tool, in addition tofunctioning in the standard jet noise prediction mode. Individual slice

calculations can be made by suitable input selection, running each slice (or

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: ', ISO. This mode permits evaluation of the

;It each frequency and observer angle.model can be bypassed to assess, for

t,, of convection, acoustic shielding, etc. Thet., predict only the jet flow field, if desired.

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5.0 CONCLUDING REMARKS

A theoretical analysis and associated computer model for the solution of

the flow field and the acoustic characteristics of nozzles of arbitrary geo-metry is presented. A large number of cases have been calculated with thismodel and compared with appropriate experimental data (Reference 3). Thecomputerized procedure presented herein provides a reasonably accurate methodof predicting the aeroacoustic characteristics of a wide variety of exhaust

nozzles over the range of flow conditions of interest, at least for thoseconditions and or observer angles where shock-cell noise does not dominate thespectrum.

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APPENDIX A

DESCRIPTION OF INPUT

The input data is supplied through NAMELIST input format, with the

exception of the alphanumeric title data card, which precedes the input

NAMELIST data. Any number of successive cases can be run consecutively,

limited only by the user's execution time available. Each successive case

requires a title card (80 - character label in columns 1 - 80), followed by

the INPUT NAMELIST. The data from preceding cases remains in storage, so

only those variables which are to be changed from the preceding case input

value need be included in the INPUT file of succeeding cases.

A suggested input preparation format is given in Table A-i. Those

variables marked by an asterisk (*) have preset values built into the program,

and need not be input unless the user desires to over-ride the preset valuewith a different one. The definitions of each of the input variables given in

Table A-I are lisced in Table A-2. Again, preset variables are marked by an

asterisk (*). The values of those variables which are preset are given inTable A-3. The format of Table A-2 is such that a note number (where approp-

riate) is given for each variable which corresponds to the note number inSection A.1 (Notes on Input). These notes give further elaboration on how to

specify and prepare the input data.

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Table A-i. Suggested Input Format.

Column2

(80 - CHARACTER TITLE CARD, COLUMNS 1-80)

$INPUT

KX ~ ___ NEST =___,LPHI* ___ ISYM=

IQUIT -_ __NN -__,NCASE =__,NBREF-

NPRINT * ____,NCBDY=

BETAIN* = _ __

DELTIN* =

ALPO = 0 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

LEAV = 1 ,_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

NUM = 1 ,______ ______,_____ ,______,___ __

KN I _____ _____ _____ _____ _ _ _ _ _

DED___________ E____________, ____________, ____________ ___________ ___________

DS =, ___________, ___________, __________ ___________ ___________

NCELL =,___________, __________, ___________,___________

[IT =, ___________, ___________ ___________ ___________ ___________

IT =,________ _______ ________,_______

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Table A-i. Suggested Input Format (Concluded).

Column2

DALP(I,2) =

DALP(i,3) =

(etc., for boundary 4, 5, 6. ..... NEST)

RA(l, 2) = ......

RA(l, 3) =

(etc., for boundary 4, 5, 6. ..... Nest)

CM* = ,CH*= ,CMVR*= CMMC* -

GAM = ,CP = ,PS = ,ALFA* =

DTHM* RU2M* AK = BK*

STRFR* = , STRFX* - , AT0TAL =

ALPHMC* = , BETAMC* =

NUMANG = , DIST = , FMIN*=, FMAX* -

ALPHT* , , , , , ,

XCBDY = , _,_, , ,

RCBDY = , _, , , , ,

$

(NEXT CASE, IF ANY)

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I

Table A-2. Input Variable Definitions.

Variable Note Description

KX Number of axial stations to be analyzed; amaximum of 24 stations is permitted.

NEST 1 Number of closed boundary contours defining

the nozzle exit geometry. A maximum of 110is permitted.

LPHI 7 Number of symmetric leaves (repeating seg-ments in the nozzle exit planform.

ISYM Nozzle symmetry indicator; ISYM = I for ax-symmetric nozzles or completely asymmetricnozzles, = 0 otherwise.

IQUIT Maximum number of radii at which flow field

is calculated (e200).

NN 12 Acoustic Calculation option indicator.

NCASE* Number of cases to be run consecutively.

NBREF* Reference condition boundary number.

NPRINT* 13 Aerodynamic station printout indicator.

NCBDY 9 Number of centerbody input coordinate points.

A maximum of 40 is permitted.

NOV Minimum number of radii at which flow fieldis to be calculated, for each axial station

(KX values required).

X 11 Axial location of each axial station, ft.(KX values required).

DSIG 11 Radial step size to be taken for flow fieldcalculation at each axial station, ft.(KX values required).

BETAIN* 15 Axial shear stress turbulence constant(KX values required).

DELTIN* Azimuthal shear stress turbulence constant

(KX values required).

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Table A-2. Input Variable Definitions. (Continued)

Variable Note Description

AMUIN* Azimuthal velocity gradient turbulence fre-quency constant (KX values required).

RMIN 9 Minimum radius for flow field calculationat each axial station (KC values required).

XE 8 Axial location of exit plane of eachboundary, ft. (NEST values required).

ALPO 2 Reference angle ao from which the coordi-nates of each boundary point are specified,radians (NEST values required).

LEAV 1,4 Number of symmetric leaves (repeating seg-ments) of each boundary (NEST valuesrequired).

NUM 1,5 Number of input points (coordinate pairs)

to be supplied for each boundary (NESTvalues required).

KN I The number of the boundary which enclosesa given boundary (NEST values required).

DEQ 16 Equivalent flow area diameter of eachboundary, ft. (NEST values required).

DS 16 Shock-cell spacing characteristic dimension,

usually hydraulic diameter, of each boun-dary, ft. (NEST values required).

NCELL 16 Number of shock cells for each boundaryelement (NEST values required).

PT 6 Stagnation pressure inside each boundary,lbf/ft (NEST values required).

TT 6 Stagnation Temperature inside each boun-dary 'R (NEST values required).

DALP(I,J) 2,3,5 Angular increment Aa from preceding boun-dary point which locates the given boun-dary point I on boundary J, radians (omitboundary number 1, ambient field).

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Table A-2. Input Variable Definitions (Continued).

Variable Note Description

RA (I,J) 2,3,5 Radial coordinates of boundary point I onboundary J, ft. (omit boundary number I,ambient field).

CM* 10 Empirical jet momentum diffusion ratespreading parameter Cm.

CH* 10 Ratio of enthalpy-to-momentum spreadingparameters Ch/Cm.

CMVR* 10 Momentum spreading parameter velocityratio influence coefficient.

CMMC* 10 Momentum spreading parameter Mach numberinfluence coefficient.

GAM Specific heat ratio y = Cp/Cv.

CP Specific heat at constant pressure Cp,in (ft-lbf)/(slug - 'R).

2PS Ambient static pressure, lbf/ft

ALFA* Turbulence characteristic frequency con-stant.

DTHM 7 Maximum allowable increment in angularcoordinate, (d )max, for flow field calcula-

tion.

RU2M* Minimum value of jet momentum flux, (pU 2)minbelow which the flow is not calculated.

AK* Sound pressure level proportionality con-stant for mixing noise calculation.

BK* Sound pressure level proportionality con-for dipole density-gradient noise calcula-tion.

STRFR 11 Radial coordinate stretching factor for useof automatic mesh calculation.

STRFX 11 Axial coordinate stretching factor for useof automatic mesh calculation.

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Table A-2. Input Variable Definitions (Concluded).

Variable Note Description

2ATOTAL Nozzle Total exit flow area, ft

ALPHMC* 14 Convection Mach number weighting factor.

BETAMC* 14 Convection Mach number weighting factor.

NUMANG Arena selection indicator; NUMANG = 1 indi-cates constant radius arc, NUMANG = 2indicates sideline parallel to the jetaxis.

DIST Arc or sideline distance, ft.,

FMIN Minimum frequency for which acoustic cal-culations are required, Hz (>50); aninteger variable.

FMAX* Maximum frequency for which acoustic calcu-lations are required, Hz (<100,000); aninteger variable.

ALPHT* Convective amplification factor turbulenceconstant at; 15 values required, one foreach observer angle e, from 61 = 20* to 1600in 100 increments.

XCBDY 9 Centerbody input point axial coordinate,NCBDY values required.

RCBDY 9 Centerbody input point radial coordinate,NCBDT values required.

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Table A-3. Preset Input Values.

Variable Value

AK 0.08

ALFA 1.0

ALPHT 15* 0.5

ALPHKC 0.5

AMUIN 24* 0.2

BETAIN 24* 4.0

BETAMC 0.325

BK 0.0

CH 1.15

CM 0.075

CMMC 0.08

CMVR 0.25

DELTIN 24* 4.0

DTHM 0.1

FMAX 100000

FMIN 50

IQUIT 50

KX 15

LPHI 9999

NBREF 2

NCASE 1

NN 0

NPRINT 1

RU2M 3.0

STRFR 0.01

STRFX 1.259921

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A.1 NOTES ON INPUT

1. The jet nozzle geometry is specified by input of the number of

component boundaries, NEST, along with pairs of coordinates, RA and

DALP, for each boundary element. The ambient field is alwaystreated as the first boundary in the input arrays for UE, PT, TT,

LEAV, NUM, KN, XE, and ALPO. This is why some numbers have alreadybeen filled in on Table A-1 in the first column for these arrays.

A nozzle with N elements has NEST = N + 1 boundaries.

2. The steps to specifying nozzle geometry input are as follows, re-

ferring to Figure 6:

a. Obtain sketch or drawing of nozzle exit cross section and

select a coordinate origin which is optimum from the stand-point of symmetry and boundary point specification.

b. Number each boundary, reserving boundary Number 1 for the

ambient field.

c. With respect to the coordinate origin, select a reference

angular location for each boundary, ALPO.

d. For each boundary, select points represented by pairs of

coordinates. The coordinates used as input are radius,

RA(I,J), and angular increment from the preceding point,DALP(I,J). For the first point, DALP(I,J) is the angular

increment from the reference angle ALP0. The index I is theboundary point number, and the index J is the boundary number.

Both ALP0 and DALP are to be input in radians, and RA is input

in feet.

3. The last point on a given boundary should be located at ALPO ifthe boundary has only one leaf. The sum of all DALP(I,J) should

equal zero if the boundary has only one leaf.

4. If the boundary is a circle about the origin, only one point on theboundary need be supplied, and the value of LEAV for that boundary

is set equal to the number of boundary points desired on the circle.

5. The program uses linear interpolation between input boundary pointu.If a boundary is made up of or contains straight line segments,only the end-points of the straight line segments need bo input.

6. The variables PT and TT refer to stagnation pressure and temperatureat the exit plane inside the boundary of interest. Setting the

first value of PT equal to PS gives a static ambient field. Thefirst value of PT greater than PS simulates non-zero flight veloc--

ity.

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7. The variable LPHI determines what angular extent of the flow fieldneeds to be calculated. If the nozzle geometry is axisymmetric,setting LPHI equal to a large number (such that 2r/LPHI is lessthan DTHM) forces the program to calculate the flow field at onlyone angular location. The flow field for a nozzle containing twoadjacent circular jets, for example, has LPHI = 4, since the flowis the same each quadrant. Several examples of how boundary para-meters are specified are shown in Figure A-1.

8. The program can currently only handle coplannar nozzles, i.e.,every nozzle element must terminate at the same axial location.Therefore XE must be the same for all input boundaries.

9. The centerbody, if any, is input through coordinates pairs XCBDY(J),RCBDY(J), where I < J < NCBDY. A maximum of 40 points can beinput. The LSPFIT subroutine uses this input to interpolate forfinding the values of RMIN at each axial location X. The LSPFITroutine can treat line segments, both straight and curved. Typicalexamples of centerbody coordinate input are shown in Figure A-2.If there is no centerbody, the user can avoid automatic computationof the potential core of axisymmetric nozzles (which has no impacton mixing noise) by specifying RMIN as input, but with NCBDY = 0.This option causes the computation to begin at r = RMIN(KA), whereKA is the axial station number.

10. The input value of CM is modified for velocity ratio and Machnumber effects by the relation

CMDBDX =

(1 + CMVR*VR)(I + CMMC*ACH)

where DBDX is the modified value of Cm, and VR and ACH are thevelocity ratio and Mach number, respectively, of a given boundary.The heat transport spreading parameter is then calculated from therelation

Ch = CH * DBDX

The values of CM, CMMC, CMVR and CH recommended and preset in theprogram are given in Table A-3. These values can be changed by theuser to reflect experimental evidence if so desired.

11. The axial locations of the axial stations can be input by the arrayX(KA), where 1 < KA < KX. The radial mesh step size can also beinput by the array DSIG(KA). An automatic grid selection procedurehas been devised to obviate the need for supplying all values ofX(KA) and DSIG(KA). The only input required is the first axialstation X(l), and the grid stretching factors STRFR and STRFX. Thegrid is then calculated from the following relations:

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TI

NEST -2

J 1 LPHI 999

ISYM 1

J 2 LEAV 1,36

NUM 1 ,1

ALP= 0,0,

KN = 1,1,

(a) Circular Jet

J = 1 NEST = 3

J =2 LPHI = 999

J =3 ISYM = 1

I = 1 LEAV = 1,36,36,

NUM 1,1,1,

ALPo = 0,0,0,

KN = 1,1,2,

(b) Coannular Jet

J 1 NEST = 2

2 11LPHI = 4

3 ISYM 0

LEAV = 1,2,

NUM = 1,3,

ALP0 = 0 ,0,

(c) Rectangular Jet

KN - 1,1,

Figure A-1. Examples of How Boundary Parameters are Specified.

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V

I ont NmberCurved Line Segment

23

Straight Line Segment3x

Repeat Coordinate

NCBDY 7,

XCBDY = X1 ,X2 ,X3 ,X4 ,X5 ,X6 (-X 5 ),X7 ,

RCBDY = R1 ,R2,R 3 ,R4 ,0,0,O,

(a) Example 1 - Curved Centerbody

r

Straight Line Segment

Curved Line Segment

/x0

Straight Line

rs S egment 0 M

Repeat Coordinate 10

Repeat Coordinate

NCBDY = 10,

XCBDY = X1,X 2 ,X3 (=X2 ),X,I,X 5 (=X4 ),X 6 ,X7 ,X8 ,X 9 (=X8 ),XIO,

RCBDY = RI,R 2 ,R3 ( R2 ),R4,R 5 ( R4 ),R 6 ,R7 ,Rs,R 9 (=R8 ),RIO,

(b) Example 2 - Segmented-Cone Centerbody with Curved Tip

Figure A-2. Centerbody Input Coordinate Examples.

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P 2,2) P(1,2)

\ k ALPO(2) P(8,A N \P(7,3)

8 P(6,3)58 ---- q \ /P(5,3)

P(4,3

LPO(9) P(3,3 (2 )RA(I ,9) 4 (1 ,3) Bsln

co -4--'1 '--- 2 3 DA P- P(0, 3) B sln

/System (1 ,3)

[ DALP 12--9(1,9)

Figure A-3. Example Demonstration of' Nozzle Geometry Specificati-,nwith a Generalized Nozzle Exit Configuration,

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X(KA) = STRFX * X(KA-1)

DSIG(KA) = STRFR * X(KA)

This provides a grid which exhibits larger and larger step sizes asthe plume is developed downstream. Recommended value of STRFR andSTRFX are preset and listed in Table A-3.

12. The variable NN determines the type of acoustic calculation desired.

Normal (preset) operation is with NN = 0, which give the completeacoustic calculation described in Section 3. The user may desireto perform diagnostic computations to assess the relative impor-tance of convectiol., shielding, etc. By selecting the appropriatevalue of NN, the various components of the acoustic calculation canbe switched on and off in various combinations. Setting NN = 4gives only the aerodynamic calculation, and the acoustic calcula-

tions are bypassed. The various options for NN are listed below:

NN = 0 - complete acoustic calculation.

NN = 1 - convective amplification, no shielding.

NN = 2 - no convective amplification, no shielding.

NN = 3 - no convective amplification, with shielding.

NN = 4 - no acoustic calculation, aerodynamics only.

13. The printout of aerodynamic flow field data is controlled by NPRINT.

When NPRINT = 0, no aerodyanmic printout is provided. If NPRINT =1, aerodynamic printout is provided at every axial station. IfNPRINT = 2, aerodynamic printout is provided at every second axialstation (i.e., KA = 1, 3, 5, 7, etc). For PRINT = 3, printout is

provided at every third station, etc.

14. For dual flow nozzles, if the inner stream has a higher velocitythan the outer stream, use ALPHMC = 0.5 and BETAMC = 0.325 (preset

values). These variables are weighting factors in the convectionMach number calculation, which is computed from the relation

MC = ALPHMC * MACH + BETAMC * EMACH

where MACH is the local acoustic Mach number U/Ca and FMACH is theexit plane reference Mach number Uj/Ca. If the outer stream has ahigher velocity than the inner stream, use ALPHMC = 0.5 and BETAMC

= 0.325/VR, where VR = (Uouter/Uinner)j. For multielement suppres-sor nozzles, VR = Uj/Um, where Um is the post-merged potential corevelocity. If Um is not known, BETAMC 0.2 to 0.25 is usually agood approximation.

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L5. For dual flow nozzles, input BETAIN = 4.0 (preset) for all valuesof X, provided the inner stream velocity is higher than the outer

stream velocity at the exit plane. If the outer stream velocity ishigher than the inner stream velocity at the exit plane, input

BETAIN = 0 for all axial stations where X ' I0*DEQ(NBREF), and

BETAIN = 4.0 thereafter, where NBREF is the outer stream boundarynumber. For multielement nozzles, input BETAIN = 0 for axialdistances less than l0*DEQ(l), where DEQ(1) is the equivalentdiameter based on total flow area at the exit plane.

16. For each boundary element DEQ, DS and NCELL are input. The first

value of DEQ is the total flow area equivalent diameter. The firstvalue of NCELL determines whether or not the shock cell noise iscomputed. If NCELL(1) is input zero, no shock noise is computed;for NCELL(1)>O, the shock cell noise routine is called. The shocknoise of each boundary element is computed separately and added tothe total noise. If any boundary has a value of NCELL = 0, that

boundary element is bypassed in the shock noise calculation. It is

recommended that NCELL = 8 be used for each element unless the actualnumber is known.

A.2 EXAMPLE CASE INPUT SELECTION

To illustrate how geometric input parameters are selected for a complexnozzle geometry, an example is presented, taken from Reference (1). Theexample nozzle exit geometry is shown in Figure A-3. Consideration of this

figure indicates information over a 45' sector of the flow field will besufficient to describe the complete flow field. This is one-eighth of acircle, thus LPHI = 8. Neither axial total similarity or dissimilarityexists so ISYM is 0. Counting the number of closed contours indicates avalue of NEST of 12, where one is included for the ambient or externalfield. Values of PT and TT must be provided for the exit state existing justwithin each of these contours. Values of XE, ALPO, LEAV, NUM, KN, DEQ, DS,and NCELL must be provided for all the contours except the first which is the

boundary at infinity. Values of these parameters for the contours shown inFigure A-3 are now considered in the following discussion.

Boundary 2: Description of this boundary starting at 450 to the systembaseline is convenient. Thus ALPO = n/4 radians. Since each 90' sector of

the contour is identical with the proceeding one, LEAV = 4. Since the pro-gram assumes straight lines to exist between successive boundary points,

description of this boundary is possible with only three points for each

quadrant. These are P(1,2), P(2,2), and P(3,2). Each point is described by

its distance from the system origin and the angle between the line joining itwith the origin and the line joining the proceeding point with the origin.Note that no value of RA is given for the point P(0,2) since it will be

identical to RA(3,2). The value of NUM for boundary 2 will therefore be 3.

Boundary 3: This contour has eight symmetric leaves, thus LEAV = 8.ALPO of 0.0 is as convenient as any other value. Ihe eight points indicatedP(1,3) through P(8,3) probably are sufficient to describe the boundary. ThusNUM = 8.

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Boundary 4: Since this is a circle about the origin it can be dividedinto a convenient number of leaves and only one point given for each (NUM =1). If a hundred boundary points are desired; set LEAV = 100, DALP(I,4)=7/50and RA(I,4) equal to the circle radius.

Boundary 5 through 12: Each of these contours must be described indi-vidually unless certain artifical changes are made in the arrangement. Apartial representation of Boundary 9 is shown in Figure A-3. Note that suc-cessive points on the boundary are obtained by progressing around the bound-ary in a counter-clockwise fashion. In order to reduce the labor of repre-senting each circle separately, a straight line can be drawn connecting eachcircle. Two contours can then be visualized, one consisting of the outerhalves of the circles and the lines, the other consisting of the inner halvesof the circles and the lines. Each contour has eight leaves and only oneneed be represented by the programmer. Since this technique requires thecomputer to integrate along each straight line twice in the course of computa-tion, it will definitely increase the computational time over the methodwherein each contour is represented separately.

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APPENDIX B

OUTPUT DESCRIPTION

The output format is generally self-explanatory. The input data isfirst printed out, using the same nomenclature previously defined in Table 2.

Nozzle exit plane flow conditions (static temperature, velocity, Mach number,momentum flux, and enthalpy flux) are then printed out for each boundary

contour.

At each axial location specified, the radial and tangential distribu-

tions of flow field properties are printed out. After the flow fieldinformation, the noise characteristics of that particular axial station are

then listed.

Following all of the axial station flow field data, a summary table of

the noise characteristics (SPL spectra, PNL, PWL, OASPL) is given.

Appendix C contains an input deck card listing and output printout for a

sample case run. This particular case is for a 7-tube nozzle presented inReference 2. Only a portion of the total output is shown for brevity, but

the formats of the various output data are all included.

Two warning flags are built into the program. The first is a case

termination flag, which occurs whenever an input total pressure (PT) is less

than the input static pressure (PS). The flag message is as follows:

****ERROR - MACH NO. SQUARE IS NOT GREATER THAN ZERO - CASE WILL

TERMINATE****

The second flag is a warning detected in subroutine SLICE, which occurs

whenever the number of turning points (NTP) is found to be greater than 2.The flag message is as follows:

WARNING - NO. OF TURNING POINTS IS GREATER THAN 2 AT

KA = , X = _ , ITH = _ , THETA = _ , NT __

where KA is the axial station number, X is the axial location, ITH is theobserver angle index, THETA is the observer angle in degrees (e1 ), and NTP is

the number of turning points found. The two outermost turning points areused and those inboard of these two are discarded in such cases, since the

acoustic shielding model can only accommodate up to 2 turning points. Thenoise output at those values of 61 where this warning appears should be

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treated as suspect, since the acoustic shielding effects are not properlymodeled. This is most likely to occur in the initial mixing regions ofmultitube nozzles where multiple peaks in the aximuthally-averaged velocityprofiles are likely to occur.

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APPENDIX C

SAMPLE OUTPUT LISTING

An example case of a 7-tube multielement nozzle is described herein,

selected from one of the data/theory comparison cases presented in Reference

(3). The nozzle consists of a hexagonal array of 0.875-inch diameter tubes,

with a spacing/diameter ratio of 3. The acoustic arena is a 9 ft. radius

arc. The geometry is illustrated in the sketch below.

Observer

SU 1

5 r.,8 t--\ 2Centerline

60 07 Boundary F MME U'jNumber

d : 0.875 in.

D 3.0 in.

The input data cards for this case are listed in Table C-1. Note that all

geometry input lengths are in feet, and all input geometry angles are in

radians. The output listing for this case follows Table C-1.

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T 71,Table C-1. Input Data Card Listing Sample Case.

5R329? LIT 1J-C6-77 16.411 INPJT DATA CARD LISTIN6 -- M-G.- ..

CRO 7-TURC AQ#?.3 Nr7?ZLF - VIJM?200 FPS - TTJbIbOfl CrG-W

NEST =8, LPHI 12, ISYM=D, IQUIT=1l32,RU2NI=3, DTHM=J.1, PS=2116,A TOT AL .C29 23 1, D E2=8 -.. 072916 7, DS=8 *C. 7 2 9

16 7o N CE LL8-3,KN~i*l, XE=S-J,

GAM=1 .35, CP=6619, *ALP=0.0,',.96144,0.72544?,.772642.8198, 3.8670,4.9142,0.J,

LEAV=0,6*1,24, NUMi=1,6*24,1, KN 8*1, XE=8*i,O ALP (1 ,2 ).*U3 3595, . 4 5592, . J 54064, .05 9862,.063 450,. 0651 68,* 06 51653,. L634 5 0,. '9 59862p,. 05 4084 ,.045 590P. 03 35 96,.017C39,-.605317,-.D34336,-.068984,-.103591o-.126562,

-. 1'656?.-.03591,-.6,8984,-.C;34336,-.0J5 3 1?o. 0 1?03 9oD ALP( (1, 3) =.03 35 9, . '45 59G. .0 54 164, . 059862 f. C 634 50 P. 06 51 68,

* 06 163, * C 6345 0. J5? 862,. L 54084,. 045590,. 033596,.017139-.005317,-.J34336,-.068984,-.103591.-.126562,-. 126562,-.103591,-.068984,-.034336,o-.0053l7,.01?C39,V ALL (1,4) =

.033 595P . (45590o .054084, .05 9862P. 0634 50,. 06 5168,.06 51b3 , .D63450.. 35? 862,. 35 408 4 . 045 590, .03 35 96#.01703?,-.0J5317,-.34336.-.06d98i4,-.103591.-.126562,-. 1?6552,-.103591,-.068984,-.034336,-.005117,.017039#DALP( (1,5). 03 3596o. C 45 590*. Ci 54084o,. 05 9862 P. 0634 50P. D6 5168..065163.C,63450,. 0 59862, . 05 4084,. 045 590. . 03 35 76o.01703 9 ,-.00531?,-.34336,-.06893 4 ,-.13591,-.12D>562,-. 126552.-.1G3591,-.068984.-.034336,-.005317,.017039,

"033596P. 045590P. 0 54084, .059862,. 0634 50, .06 51 68

.01703?e-.005317,-.034336.-.068984,-.103591,-.126562,-. 126552,-.103591,-.1J63984,-.034336,-.O05317,.017239,D ALP(C I,? ) =*033 595. & 045 590, . 0 54084,. 05 9862. 0634 50,. 06 51 68*.065 163 . U634 50P. 059862,. 05 4084,.045 590P. 0335 96o.017039.-.005317,-.034336,-.068934,-.103591,-.126562#-. 1?6552,-.103591,-.068984,-.034336,-.005317,.017039,R A( (1,2)* 12392e.13145,.13 759,. 142 12,. 14 489.14583,. 14489,.*1 421 2P.13 759P .131 45,o. 12 392,P. 1 15290. 10596, . 39646, .03 748, .07991 , .07476,.0 7292,P* 07476,. 07991, .08 74, . 09646,. 10 596,. 11529,R A( (1 , 3)=

.07476.3799l,.03748,.09646,.10596,.11529,

12392,.1314 5,.13 759P.142 12,. 14 489,.14583,

10596, . 0646, .C6748,. 07991, .0? 476 ,.0 7292,

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Table C-1. Input Data Card Listing Sample Case (Concluded).

5R529 Cl 1 0-C6-77 16.471 .** INPUT DATA CArD LISTING -- M*G*d *.

.07476,. D799 1,.09 748, .09646,.10 596,. 11529,RA( I , 5)

.12392,. 1314 5, .137 59,. 142 12 ,.14469,.14583,

.14489,. 14212,.13759,.13145,.12392,.11529,

. 10596,.. J9646, .L3 749, .07991 .07 476,. 7292,

.07476,.h 7991,.*C 74, .09646,.1) 596,.11529,RA( 1 6) =

.12392,.13145,.13759,. 14212,. 14489,.14583,

.14489,. 14212,. 13759,. 13145 ,.12392 ,.11529,

* 10596,. :9646, .06 745, . 07991 ,.07 4?5 ,. 07292,.074 76,. D 7991, .03 746, .09 46,. 10 596,. 11529,RA (1 , 7)-

12 392,. 1 3145, .13 759,. 14212,.14489,. 14583,

.1449, ..14212,.13759,.1314 P5,.123

92,.11

529,

.1 0596,.;9646,.08 748,.07991 ,.07476 ,. 7292,

.07476.. D 7 991, .TP 748,. 09646 f,. 10596,. 11529,DAL ( I.) 2.2618, RA( 1,8)= .03645 ,

ALPHMC=fJ. 5, BETA4C=3.25,

FM.N=z1C, FMAx=8000, NUMANG=l, DIST=9.O,KX=)4, X=(.0729167, STRFR=9.01,

USIG=10 3.3Jl729157, 14*,, NOV=10*20,14*J,

BFTA IN=15-* .C,NPR N NT=NCASait

PT=2116,7*573?, TT*; O,7*160l ,

S

63

Page 79: OH AIRCRAFT ENGINE GROUP F/6 20/1 292 HIGH VELOCITY ...2" 11* v o~ftz j & nr, source locamzw amu 2 reductionw task 2a., supplement ... lia r78aeg324 high velocity jet noise source

CflMPlJTATION OF AE*O-ACOIj',0 a P " PERIIE-S F -- 4F 0.C ', LS

CASE I. ) Cwl. 7-TI),E AP=2. I '7."LF VJ= ? 0 F'P, - TTJ= 00 OF ;-P

1P.PIT DATA

KX ?4 NEST= 6 L,)HI= 12 ISYM= j NPOINT t6 Cm=

.075

cm= t.1-,C GAm= 1.3-' CP= 6h19.0 irTHm= .1(00 PI2M= 3.0000 PS= 2116.0

. COPUTATV1' MESH CONjTPOL PARA4EOEPS ........................ TUPLILECE CONSTA .TS

- -- SLICE NG. X - - - - SIG - RU'IN -- OV - PETA -DELIA -- MU

1 . 2 .0672?4 C.C --- ?0 . o 0.00 4.00 .20... 2 . 1 ? 7 .05720T 0.0000 2, _ 0.O _-4.00 __ .20-

3 .I 117c; .. 77?9 0.00000 2) 0.00 4.00 .20. .. 4 _ .4,583 .3C72. 0.000% 2) __ 0.00 4.00 .20

S .IA374 .r72l O.00O' ?) 0.00 4.00 .20- ?3='1 _ C.r 7'01 Q.00^0 __6 0. ' 4.QQ_ .20_7 .20167 ."7- 0.oCCo 2,' 0.00 4.00 .20_ .7 748 .- 72 -' o, ?n - 0.00 4.00 .20

9 .0 "7 . ,"0000 0. ? 0 i.C0 4.00 .2013 .56313 .0:7?9 0.0oo00 20 0.00 -4.00 _ .20

11 .73.q5 .0r7 1.c;0C C. 0.00 4.00 .20

. ....... 12 5.9?5-'1 .__ _ ---------- ."')0 V _. ... Q* _ _. .o . .0.13 1. 1A.67 .ol I1 7 U..) 0.co 4.00 .2014 I. 41 '. 1,7, 0..7a 3000 0 . 0.00 4.00 .20IS;

I .'l I Q7 . I .1 C. ()n, 6 0.00 4.0A .20- - 1 2.111)3 .02323 '. :rt) 0. 4.00 . .00 .20

17 2.q0TQ2 .0?,4, O..oCCG 4 4.00 4.00 .20S ___.18.. .7j3, -1)37l~i.0 03 4____ l .00-4_ .. 00 - -__ 20

19 4.066667 .04667 O.CO000 0 4.00 4.00 .20..- -.... 5.87963 - ____.05660 ___ _ 0.0000 ___ 04.00 ___o_.O0 .2021 7.4,767 .07408 0.00000 0 4.00 4.00 .202 -......... 9.33333 _ 09331 _ .00000 0 4.00 __ -00 -. 2023 11.75926 .11759 0.00100 0 4.00 4.00 .20

_____21 14-81574 - I -UL o.000 0o 4.00 4.00 .20

... XE = O.0 ALPO (- 2= 5.961 4 L?4V L -L -4UM-L-I- - -NL2-= - K____1_

___ DALP 1 .21= .3336 -RALI -2)=- 239- DALP.(_-2)= .456-__RA_ 2t1_=__-__.315 ....

_AlP(-_a2.24 4I PA( 3 21)= .13"76 DALP( 4. 21= .0599 PA( 4. ?) .1421

DALPi 5._2)=__.135 --. 4-.92= U 9_AALP_6._--= .06,2--RAI.2) .I4

- DALPI 7. 2)= - .0652 -_JRAL7. -2)-= ... 1449 DALPLSa.2Z =-- .0.65- RAIL8L -2) .1421 -_

DALP( q, 21= .*159q RA( 9. 21= .1376 DALP([O. 2)= .0541 RA(IO, P)= 1315

n___ __lALP11 -2: _3.456 A(IIl.-2 1z .1239 DALP(12. 2)= .0336 .- RAL12. 2)a .1153-

--....... DALPA3L.2l~7 -~AI~-I3D 2l=_.1260 DALP4_ Z0--.(L05a__ RAAI14-p- ? .0965-...

____________-DAL'!Si .21= 1 LL.i2L 07_ _3AL1--IAL 21 -. 0690 RA(16, 2)= .0799

..&. . 1.7'';. 2)= -. 103 _RA( 17.)= .0748 DALPlIBa. 21 - .1266 RAiLSg2= .0729___-

OALP(10. 2)= -. 1266 WA(IQ. 2) .0740 DALP(20, 2)= -. IC36 - .Pa020, 2)= .0799

_? DAL2LL21=. . (,l, 2) o..0175 DALP (221- 2)_-.0- . Q43__R AJ L2)--l=a_9&____

DALP(23. 2)= -. 0053 PA(23. 2)= .1060 PALP(24, 2)= .017a RA(249 2)= .1153 _

64

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• M G 1 ** •PAGE d

COMPUTATION OF AERO-ACOUSTIC PROPERTIES OF SUPPPESSnR f4OZZLES

CASE NO, I CP 7-TURE AR-?.3 NOZLE - VJ=??30 FPS - TTJ-1600 OEA--

XEI 3)- 0.00 ALPn( 3)= .7?54 LEAV( 31= I NUMf 31= P4 KN( 31= 1

. ALP( . 3)= .031h PAI I. 3)z .1235 OALP( ?, 3)= .0456 PA( 2. 31- .1315

DALPI 3. 3= .0541 RA( 3. 3)= .1376 [ALP( 4. 3)= ,U599 RA( 4, 31= .1411

DALPI 5, 3)= .0635 RAI 5. 3)= .1449 [1ALP( A, 3)= .U65? PA( 69 3)= .1458

I)ALP( 7. 3)= .0652 PAI 7. 1)= .1449 I)ALPI A. 3)= .C635 PA( A. 3)= .14?!

DALP( 9. 3)= .05v9 RA( 9, 3)= ,037t IAtP(Il, 3)= .t'41 RA10, 3)= .131S

OALP(1I, 31z .0456 RAII, 3)=- .1239 lbLP(f?. 3)= .0316 RAWIT, 3)= .)153

DALPII3, 3)= .0170 PA(13, 3)= .106U DALP(14. 3)= -,"05" PA(14. 3)= .0965

DALP(IlS 31= -.n343 RA(15, 1)= .0875 nALP(l,. 3)= -. U 60 RA (6. 3)= .07c49

DALP(|7. 3)= -. 1036 RAW1, 3)= .074H lALP(lR. 31= -,9266 PA(9i, 31= .07 9

DALP0I9, 3)= -.1?66 RA(19, 31= .0148 (OALP(?0. 3)= -. 1(36 RA(?0. 31= .079

DALP(21, 31= -.0690 RA(71, 3)= .0875 I)ALP(??, 3)= -. 0143 RA6??, 3)= .09A9

OALP(23. 3)= -.0053 -RAA213 = .9060 DALP(?4. 39= .0170 A(24. 3= .11513

XEl 4)- 0.00 ALPOI 4)= 1.7726 LEAV( 4): 1 Ntlm( 4)= 24 'N( 4)= 1

OALP( 1. 4)= .0336 RA( 1, 4)= .1239 [ALP( ?. 4)= .04')6 RA( P, 4)= .131c

DALP( 3. 4)= .0541 RA( 3, 4)9 .1176 OALPI 4. 4)= U5 9 PA( 4, 4)z .14?1

OALP( 5, 49| .0635 WA( 5, 4)z .1449 DALP( 6, 41= ufb? PAI f. 41= .145P

DALPI 7. 4)= .0652 RA( 7. 4V= .1449 OALP( S, 41= .0635 RA( S. 4)= .94?1

DALP( 9. 4)= *059q RA 9. 4)9 .1376 9ALP(IO, 41= .0141 RA10. 4)= .1315

OALP(II, 4)= .0456 RAMI1. 4)= .1239 DALP(12. 4)= .0136 RA,?. 4)= .1153

DALPII3. 4)= .0170 RAM.3 4)= *963(ALPl94, 4)= 9A'53 P(14. 49= .0965

DALP(IS. 4)= -.0343 PA(5, 4)= .0875 DALP(16. 4)= -. 0690 RA16, 4)= .0799

DALP(17. 4)= -.1036 RAM7, 41= .0748 )ALP(I. 49= -. ?66 ( P9I9, 41= .0729

OALP(9. 4)= -.1?66 RA(*9. 419 .074P 30AtPIO, 4)= -. 1036 PA10. 49z .0799

DALP(21, 4)9 -.3690 RAMP , 4)= .075 OALP9??. 4)= -.6343 RAI?. 4)= .0965

OALP(23. 4)= -.0053 P69(?, 4)= .10603 DALPI?4. 4)= .0170 PA94. 41= .1153

65

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** M G R P PAGf 3

COMPUTATION OF AERO-ACOUSTIC PROPERTIES OF SUPPRESSOR NOZ.ZLES

CASF NO. I COD 7-TUE AP=2.3 NOZZLE VJ=??O0 FPS - TTJ= 160O nEn-P

XEI S1= 0.00 ALPO( 5)= 2.8199 LEAV( 51= I NtI( 5.z

24 KN( 51=

OALP( 1- 5) .0336 PA( 1. 51. ti nALP 2. 51= .0456 Pit 2 5)= .1315

DALP( 3. 5)z .0541 PA( 3. ,)= .1376 rIAL-PI 4. 51) .0999 PA( 4. r,) * 14?I

OALP( S. 5) .0635 WA( 5. 5)= .1444 fALVP 6. L= .065? W0( 6. 9)= .1456

DALPI 7. S)- fl652 RA( 7, 5)= . 1 4 4 ') IALfPI H. =l= .4635i PAll HI.', 1

DALP( q 5)= 0S99 PA( 9, 5)= .137h DAIPIO, = ,0541 PA(lo 51 .131;

DALP(1I1 5)= .0456 RA(II 51= .,139 DALPII? 5)= o0336 PA(12 5)= .1153

DALP(13. 51= .0170 RAM1. 5)= U1(60 IALP(14. S)= -.0053 RA414. 5i= .096S

OALP(15. 5)= -.0343 1A(IS, *4) .047, [)LP ; = -.(1 . --- , 5----= .079q

DALP(II. 51= -.1036 RA(lW. 51= .0748 DALP(IS, 51= -. I?6b RAIIS, 5)= .0729

-OALPIlq. S)= -.1266 PA(19. S)= .0741 DALPI?0. -. 103 WAt?0O 1= .079q

DALPI2I, 5)= -. 0690 RA(21. 5)= .0875 DALP(??. 1= -. 0143 PAW?, 5 O= .0965

DALP(23. 5)= -.0053 RA(23, -)= .106 PALP(24. 1= .0170 PA(?4. 51= .I163

XE( 6V= 0.00 ALPO( 6)= 3.9670 LEAV( 6)= 1 NUIM( 6)= ?4 rN( 61= I

(ALP( 1. 6)= .0336 RA( 1. 61= .l?1- DALPI 2- 6)= .04'6 PA( ?, t)= .1315

DALPI 3. 6)= .0541 PA( 3. 6)= .1376 OALP( A. 6) .0599 PA( 4, 6)= .1421

DALPI 5. 6)= .0635 PA( 5. 6)= .1449 DALP( . b)t= .069? RA( 6. 6)= .149A

DALP( 7. 6)= .0652 PA( 7, 61- .1449 DAI.PtH. h)= U0635 1kh( , h)= .14?1

DALP( 9, 6)z- .099 RA( 9. 6)= ,1176 DALP(IO. 61= .0541 PAMO, 6)= .1315

DALPII. 61- .0456 PA1. 61= *1?3Q

OALP(I2. 61= .0336 P4W1. 6)= .W153

DALPII3, 6)= .0170 PAM(3. 6)= .1060 DALP(14. 6)= -. 0013 PA(14. 6)= .096S

DALP(|), 6)= -.0343 PA(IS, 6)= .0475 UALPII6, -)= -. 0690 A(16. 6)= .0799

DALP(17, 6)= -. 103t RA(17, 6) .074h DALP(II, 61= -.o?766 RA(16, 61= .0729

DALP(I1. 6)= -.1066 PAl . n1 .474H DVLP(?0. I)= -. 1u36 A(?. 61= .0799

DALP21. 61= -.069n A(21, 6)= .3d7, [lALG?1,. 6)= -. U443 PA(??. A)= .0965

UALP(23. 61= -. 0053 PA(?3. 01= .1360 OAP(24. h)= .0170 PA(?4. t)= .1153

66

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tn) -c -, C\. a a '.

-LX '~ - i ~ '. 0 C L

I4 .~ 3 1 - 0a

iti

it 'C ) ILI i\. zI C ( ( C '

c I -T I ~ ' 3 4 N ' C

2 N N N N N N

4 4

.2 - i~ ' N - ('. i~r' N 0'.2

C ~ ~ :L or 4 4 4 4~

-,' Z4CJ-- C - LE t\ ' 'C 2' 4 C C' ' It

I ~ ~ ~ L ii '- 4L C 0' ' ' 'C C C i

a N ~ ' I 'C C IC .3 -a 'C C '

N < < ~ ~ 2 1 N

i..: 67

Page 83: OH AIRCRAFT ENGINE GROUP F/6 20/1 292 HIGH VELOCITY ...2" 11* v o~ftz j & nr, source locamzw amu 2 reductionw task 2a., supplement ... lia r78aeg324 high velocity jet noise source

LLJ a cc c occo aC, CD r

)-) -- . 4 4 4

I- y -

ccC

a u

C' Cr cya ,

a a

If zCL

It-

a. Nf -r u-a rL

U.. C C, .

- . )- U~fJ ~f68

Page 84: OH AIRCRAFT ENGINE GROUP F/6 20/1 292 HIGH VELOCITY ...2" 11* v o~ftz j & nr, source locamzw amu 2 reductionw task 2a., supplement ... lia r78aeg324 high velocity jet noise source

~~~~ 6 E rc4 s

'OMP TA AT 1 -'N O A o - A '-TIT C Pp'[ 'E P TIEFS (J I A) Pp cS p OP l~ f07

IAS 5O- pr 7-ru<(' AP=P-i .n 7 L r - VJ=??C.l FPS -TTJ=Ikoo nFC,-P

4XIAL LOCATTON = 7''2 (/F = I Oponli'i")

'I'F f.S T T TF' * f/Lli T i'IT .T

I C I C1'.4' . tl O9.A 1 19. 7 1~0.2 . . ' .'iI .$ GC1 1" ~ 1 4 *4~ * ti,)'. I ~'-* 7 *.' , *0 ~ '~ I o* ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ) 1Q3 *i ?4.t0 !'Ii.~ 1'h5 > o *

3~ ~ ..-' cC (1A ( C)99Z 'A 7 * u'0 . 04 *? h

2199 CC4950~ (13.3 19 & *0 ? p9 0;uu 0

4 ;) 71P ~.0 c4 Y0Q'4< (I t1 31 099. *U 9 .3 U000r. . (2)' 3'o ] 4oov 1 1T4. 31 * 99.i- 4 .0 30 .A0 0J

4 .92917 'I.,, "1'.

01219 1?9S 95 ~ .5~l .0

6 * m . . s -* ,,' 1 r 1 ~ * * I * , v f l' o 9, 7* 2 ) 5 ?40 9 . I 7 i * 0 'r ?Q-4 7 - 1i .4 70 IA' I ) s- I.~ 3, 370 *-1~~ ~ 1 ~ . 1 3 7 3; , .) ' 7 * ' 6f o 1 42 7 *0". i . I H 5 0?C 7'2~ ?4 1 17 .1.1I~ P c.1 3~.S .14 .n 0n0P L4 " 1 .7* 7 0 i~-, ~ 1 1i4 1 P' .' . 74I * o

7 .4 7 '~7 1?9 721 4, 7215/ .> l ' * '? 2 4O o6 ' ~ " I . A' 1 4 . ' 1 O ; 7 24 14 r 5?99 ~ . 4 0 77 ."17

3i P,9 1:01'P > ~ .' 2 7 . 4 2 iOl(7~~~ 7 '.~ 17 v so; 3?s.42 .~ ''~ .0'?0 7H -'00 .- 47s 2'- .2 01 16~~' 7,)5 . 0 19 7 .034200 1 0

01 17 1 .2" 73 s-1 1rp'), 7 (.cs. 79 25 13 * oo4-7 4's 7.*r ,? ?11, '-12 . 001 .002 *700

7 4

71 u 7 1 ;f . L; -4 1 w .027k' 0 vf. 0 n7 7s~

,175~1*~~~~~ u'~- I . 0 * ' > 7 '' '. l . 0 p . 0 ~ - o7 - V -. " .~ r , ' 9 n' I') t. , u.0 0. ( . 9 0

?691

Page 85: OH AIRCRAFT ENGINE GROUP F/6 20/1 292 HIGH VELOCITY ...2" 11* v o~ftz j & nr, source locamzw amu 2 reductionw task 2a., supplement ... lia r78aeg324 high velocity jet noise source

* * p ( P * * * PAGE 7

COMPUTATION OF AERO-ACOOSTIC PROPFPTIFS OF SIJPPPFSSOP NOZZLES

CASE NO. I CPO 7-TIJRE AP=?.3 rnZZLE - VJ=2?00 FPS - TTJ=1600 UF0-P

AXIAL LOCATION = .07292 (X/0EU = 1.00nOc)

m P ANGLE U OF NS ITY TEMP. U/UPL TOPH.INT. P/DEQ

9 .05831 17.14 O.uO .0o?283s 541.00 0.00000 0.00000 .00olu9 *r5831 21.43 0.G!, .00?2835 546.00 0.00000 0.O00OO .t 00)09 .1;833 25.71 0.' n 00??835 54 ,0f 0.00000 0.00000 .0009 . 5933 30.oC O.(' .0??35 540.O ).00000 0.000O0 .bn00

10 .065,3 0.O ?03.37 .5016986 72,94 .09246 .04216 .qOOoO10 .O6563 4.29 169.-,c .9017420 707.84 .07638 .03710 .9000010 ..066 9f.7 05.34 n09676 66.?5 .04335 .02447 .9000010 .06563 12.66 33.4q .(020323 h06.71 .01523 .01067 .9000010 * .- 6563 17.14 5.94 ,'0?1 F, it, Ag .0026 .0C3 ? .9-00010 .;c6563 ?1.43 0°3 ,?02?835 54L,0' (,00000 O.00O 9003010 ."6563 ?5.71 0?g .?83r 54,C 0.00000 0.0'J000 .900001C .?6563 33.01 V 0. .3022935 5..CC 0.00000 0.000U0 .C) 0011 .07?Q2 0.00 1378.45 D011599 1163.19 .6267? .13779 1.O00001 .o72Q? 3.7c 1282.33 .'011754 1)4q.07 .58302 .13990 1.6000011 ,729? 7.50 1015.37 .C012396 9q4.75 .46165 .13664 1.00000II .1729? 11 .25 608.69 .0013P46 g9 ,'.58 .?7674 .10947 1.uO00011 .0729? 15.00 i,?.76 .^016504 747,13 ,11037 .05941 1.000011 .0729? 18.7- 57.?C .301 955 6?9.6V .02600 .01S4 1.00000I1 .0729? 22.50 6.44 .0?1637 564,90 .00293 .00179 . 000011 .072q? ?6.?5 0.00 .uO?R9 35 54,.0 0.00000 O.OO0CO 1.00000II 7?9? 3A .0 0.(0 .00??R39 54,.0C 0.00 00 0.00000 1.0)0001? .09021 0.0 ?145.74 .'1011Q6 12(19.4? .97558 .05249 1.10000I? VO021 3.75 2124.S4 .0I02?66 12(1.14 96594 .06441 1.1000012 .08021 7.50 2025.14 .00i0525 1171.60 .92075 .10460 1.100001? .0f021 11.25 1717.49 .0( 1]0? 1115.68 .78087 .I9R5? 1.1000012 .OROl 5.GO I 0q.87 .9012>70 1r04.97 .4FHP .16340 1.100001? 01.70 353*,4 .0)1544t 79H.27 .16C74 .08533 1.1000012 .08021 22.50 53.70 .0C19669 627.C3 .02441 .ORRO 1.10000I? .090 26.2 2.21 .0017P1 567.69 .00100 .003A4 1.100(012 .0021 30.00 0.1° .002?90 545.00 0.00jOO 0.00000 1.160013 oO87-o 0.00 21QIq .°009950 123.3u .Qq9)H .00213 1?000013 .08790 3.33 21I8.94 .D009(52 1?39.&7 .99977 .00.50 .20000

13 .09750 (.(7 ?16.f4 .0009967 1?37,1? .9987? .01146 1.2000013 .087C0 ].oc 2175.80 .0010076 12?23.8, .9925 .04213 1.2000013 .08750 13.33 ;0QP.46 .I 10509 1171,47 ,92408 .11990 1.2(00013 .0A7c0 16.67 1500.16 .0011379 1 OP3.l .68206 .1861C 1.?000O13 .08750 10.00 616.35 .)OI3HR 81.1'. .28023 .I9u?9 1.2000013 .087O 23.33 110.21 .001P367 671.34 .05011 .03566 1.2000013 .08750 26.#7 7.95 .A02152 572.14 .00357 .00463 1.?000013 .08750 3J.o0 0.90 .y2?P 35 540.00 0.00000 0.00000 .2000014 .A94 7 0. 0 219.4r .,000948 1239.57 1.0000 .00140 1.3000014 .9479) 3.33 2199.45 .o009q48 1239.57 1.00000 .00161 1.300001. .A9479 6.67 2109.44 .(O09L4R 1?29.55 99999 .00087 1.3,00014 .09479 10.00 2148.75 .0009951 12?8,90 .99968 .005F3 1.3000014 .o(474 13.33 2175.18 ,n01007A 1223.48 q897 .04684 1.3000014 .0947q 16.67 1911.43 .0010745 1147.62 .86905 .15684 1.3000014 .09479 ?0.00 1022.0 .0 01?373 996.57 .4646q 17t?1 1.3000014 .nQ47q 23.3- 29H.7r .9I16929 72H.7Q .09489 .06o7 I .39990

70

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COMPUTATION OF AFRO-ACOJ-TIC P'OPf-PTIFS O SI.PPPSSOM N)7ZLS

CASE NO, I CkD 7-TIIPF AP=2.i N077LF - VJ=??00 FP, - rTJ=i600 nEr-p

AXIAL LOCATION : *o 7?9? (X/DKQ = 1.000uo)

m P ANSLF 0 1FtISI TY TFMP. U/tLAF rUPH. INT. P/OEO

14 .,9479 ?6. ,7 14.75 ."0?1I6 59?.59 .00t71 .00707 1.3000014 .lq479 3.03 0.? .00?2 35 54f.00 0.00000 C.00000 1.3006015 .10209 *.fl 2109.4; .,)00gq4k 1239.57 1.0000 .00031 1.4000015 .10?OR 3.0, ?19.45 .9O009'.9 1?39.57 1.00000 .001% 1.4000015 . 0208 6.00 ) .09,45 . (99n4 1239.57 1.O0oO0 .GGl40 1.0()00015 .10208 9.00 ?19.45 .9009948 1239.56 1.00000 .001" 1.400coIS .10209 1?.n) 2158.55 .C000954 1?38.72 9995 .00723 1.4000015 . 0?0A 1.00 261.A3 .uoIu135 1216.62 .%e280 .0616u 1.4000015 •lc?OP 1F£.00 l o] . 1 0o 21 II29.12 F,1907 .176mc5 1.400UO

15 02 08 ?1.0O k-4.46 ?'01?917 9r4.61 .1793Q .16055 1.4000015 .1020 2I.0C 146.71 .0017738 h95.1 .O67o .0453 l.4o00015 .10?0p 27.00 9.45 .I021459 574.63 .00430 .00516 1.400001 .0?08 C. .0 . ! ??P02935 54(r.f 0.00 00 0.000C0 1.4000016 .1093A 0.00 ?10q.45 .000994R Il?3.57 1.00000 .00104 1.5000016 .1091R 3.CU ?199.4; .00Q09hA 1?39.57 1.00000 .002?? .o500016 .10938 6.0 ?.19.45 .009948 1?q.57 1.00000 .00?7? 1.5000016 .1039 .r 219q.4c; .003994R 12Ph.56 1.30100 .00 1? 1.5000016 . 093A 1?.00 219.-! . 000953 128.45 .999t1 .Onq 1.5000016 .I093A I.0 ? .161.1R ."010137 1?)6.41 .98260 .06159 1.5000016 .10938 1H.OC 1752.C Q .0010996 1121.4) .79660 .181 ? 1.500 016 .I0939 21.0.) 710.45 .'013394 ?0'.63 .32301 .14531 1.5000016 .I1093R 24.0n 98.26 .001A6I9 062.41 .04 4 hR 0 32cg 1.50000

16 .1091P ?7. C 4.P] .002 136 564.70 .o01? .00363 1.5000016 .10937 30.01 0.00 C022835 .500 ? 0.04 .0UO 0.00007 1.5000017 .116(7 13.04 2199.43 .000994P 1239.57 1.00000 .00751 1.600017 .11667 2.73 ?199.45 .000994 1239.97 1.00000 .0023 1.6000017 .11667 91.9? 239.47 .001994P 72.44 *l0000 .051 1.6000017 .11667 2.18 209.45 .00994 123q.56 1 o0.00 .001r7 1.6000017 .11667 1.27 ?0.9l .00399c; .390.4 .99915 .00i57 I.tOO17 .11667 13.f4 ?174.3 .C000 13.34 .8 5 007.004751 1.6000017 .11067 10.0 1Q).4 .010 75 114. 7) .P6,74 .15670 1.000017 .11667 2L.79 I1q9.43 .0009049 Q99.94 .07241 .1 474 1.6000017 .11667 21, 2309.47 .P0l9o4 742.44 10P7 .063 .6000017 .11267 ?4.S5 ? .71 .0000o0 13I.2 .0094? .0087, .6000017 .11667 17.7 10.1n .00035 11.460 C.00000 0.00000 1.6000017 .11667 3C.60 0.2) .002035 54o.0( .O0UO 0.00000 1.6000018 .1239l6 1.O 1433.Q7 .4 094R9 I 179 .;7 .19vO0 .001 4 1.7060018 .2396 P.73 19.45 .D004 7R 1?4.7 1.00000 .1011 1.70000Is I ? 390 1;. .& 2| Ir4C4. 4 - .()000 9 4R 1;1)'. 56 I°00Q00 .0 61 (1p .700,1018 .12 lq6 ti1 . 2R?1 (9. 13 . o0 O I 19 .°11 .91498" .00436 .?7000018 .12 1'6 1t).91 ;319 .7 1 . ) 1no 1 3 1 P31 .46 .9(45 1 .0 ' 1 7 1.7000018 .1?396 13.64 0 1. 0 .001046L 117H.31 .931-59 .11403 1.70000Is .I1 9il I h. 16 1413.H7 . ^Ol11.7kl 11-74°2;6 or,14 I I 468 ° 7000018 .12396 19 .19 47H.5r .',0014574 e40. I .2 1o .10 756 1.70000

18 .12396 ?I.R2 P .2P4 .0019401 tfV. c,6 .01897 .02146 1.7000018 .1 p90 24.55 2.p0 .uO1965 561.37 .00121 .0034? 1.700001s .12396 27.27 0.110 .0022935 '4n.00 0.00000 0.00000 1.7000019 I .? I()., p.. H00 A ',4 1 r0 .3.0000r 0 11 1) A001 r, I.70.oo

71

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M G R PAGE 9

COMPUTATION OF AERO-ACOUSTIC PROPEPTIFS OF SjPPREsSOP NOZZLES

CASE NO. 1 CPO 7-TURE AP=2.3 NOZ?LE - VJ=2?O0 FPS - TTJ=1600 DEG-P

AXIAL LOCATION = .37?Q? (X/DEO = l.000")

M P ANGLE U OENSITY TEMP. U/UREF TUPB.INT. R/DEQ

19 .13125 .00 19q.19 .1009950 1239.32 .99988 .003?9 ).90000

19 .13125 2.5" 2196.9q .009951

1239.12 .99979 .00412 1.O0000

19 .131?5 S.03 ?1q7.42 .)00996P 1237.75 .99908 .00926 1.8000019 .131?" 7.5 2185.40 D010630 12?9.37 .99361 .02954 1.8000019 .131?5 13.o ?16.46 .r 0103?1 1194.73 .95772 .08446 1.8000019 .13125 1?.50 1776.53 .uGlO963 1124.8- ,R0771 .15885 1.8C00019 .13125 15.00 1038.?? .001?3?7 I(uou.33 .47203 .16182 1.80000

19 .131?c 17.50 318.73 .9015743 783.25 .14491 .07710 1.RO00019 .13125 2o.00 47.64 .198119 6

2c.91 .02166 .. 163R 1.89000

19 .1312 2?.Sc 2.R .0021988 560.79 °20131 .00320 1.'000019 .1312; 25.00 0. 0 .00?2835 540.0) 0.00600 0.00000 1.10000

19 .13125 27.59 0.20 .9022835 54C.09 O.On(00 0.00000 1.80000

19 .131?S 30.03 O. O .0022835 54 ..00 0.00000 u.00000 I.E000

?0 .13954 A.On ?145.6R .0010196 1209.39 .97555 .05?55 1.9000020 .13854 2.50 ?l?9.MS .3010;>4 1203.09 .96835 .06116 1.9000020 .13854 5.00 ?061.C6 .0010438 IIPI.39 .9374q9 .0886 1.90000

?o .13854 7.51 1867.77 .0010520 1139.60 .84920 .13235 1.90000?0 .13854 10.50 1436.1? .0011483 1v73.86 .65295 .16129 ).9000020 .13854 12.50 796.51 .0013?1? 933.33 .34-395 o12Q13 1.000020 .13854 15.00 231.75 .0016626 741.66 .1C537 .05730 1.90000

20 .138c4 17.50 -7.77 .0020185 611.90 .01717 .01295 1.9000020 .13854 ?0.Oc 2.50 .9022007 560.32 .00114 .00319 1.90000?0 .13854 22.50 0.00 C02-835 549.00 0.00900 0.00000 1.9000020 .13854 25.00 0. n .0022P35 b40.00 0.00000 0.00000 1.9000020 .13854 27.90 O.00 .0022835 941).00 n.00000 0.00000 1.90000

20 .13854 30.00 O.c .0022835 540.00 9.00000 0.00000 1.90000

?I .14583 0.00 137A.11 .0011599 103.10 .62657 .13781 2.0000021 .145R3 2.31 1303.87 .1011715 1u5?.5? .59281 .137q6 2.00000

21 .14581 4.6? 1100.6A .0012170 1013.17 .50043 .1349S 2.00000?2 .145R3 6.9? 773.97 .001315 938.05 .3518q .11671 2.0000021 o145R3 9.23 414.00 .0015092 H21.91 .18823 .08055 2.00000

21 .145P3 11.54 154.16 .0017639 6Q9,08 .07009 .03R61 2.00000?1 .14c53 13.85 P 7.1? .0020?04 610.3? .(1688 .01201 2.000021 .14583 16.15 4oq7 .0021826 564.95 .00226 .00328 2.0000021 .14583 18.46 0.10 .3022835 54(.00 0.00600 0.00000 .G000021 .14583 20.77 0.0) .00?PA3q 542.00 0.00000 UOUoOo 2.00000?1 .14583 23.08 0.10 .0022835 540.00 0.00000 0.00000 2.0000021 .14583 25.3p 0.0' ,6022835 54').00 0.00000 0.00000 2.00000?2 .14581 27.69 0.)o .0022835 54).00 0.00000 0.00000 2.0000021 .14583 30.00 0.00 .1)022835 541.00 0.00000 0.00000 2.00000

7? .15313 0.00 203.27 .001698A 725,85 .0924? .04220 2.10000?? .15313 2o14 1A1.15 .0017236 715,40 .08236 .03R75 2.100002? .15313 4.29 131.99 .0018010 6R4,65 06001 .03049 2.10000?2 .15313 6*43 73.?Q .001q140 644,25 .03332 o01912 2.1000022 .15313 8.57 31.17 o0020427 603,66 .C1417 .00955 2.100002? .15313 10.71 9.03 .00215?4 57?,88 .00410 .003q6 2,1000027 .15313 12.86 1.10 .0021963 561,44 .00050 .00274 2.1000022 .I5313 5.'I I 0.0 .002235 i4r. O O.C0000 0.0000 ?.0o0o0

72

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* * * M G R * * PAGE 10

COMPUTATION OF AE7O-ACOIiSTIC PPOPERIIFS OF cIIPPRESSOk NOZLES

CASE NO. I CPD 7-TiJRF AP=?.- N0o7L[ - VJ=??00 FPS - TTJ=1600 nEt-P

AXIAL LOCATION .C7292 (X/DEO 1.000or'

M P ANGtF U {F'4SITY TEMP. (J/UPEF TURn. INT. P/DEO

22 .15313 17.14 0.',o .J2235 540.¢C 0.00000 9.00066 2.1000

2? .15313 1'.?q 0.;0 .o2?A3l 54"'0V 0.000G0 0.000% 2.100002? .15313 P1.43 5.,- .102??35 34-.ot 0.00000 0.00006 2.100002? .15313 23.-7 0.(': .C02?35 5400 0.00000 0.00000 2.10000P? .15313 2.71 O.rm .C022835 q4 0t,, 0.000)0 (.00000 P.10000?? .15333 27.s6 0.- .CO22835 540.00 0.00000 0.00000 2.10000P? .15313 30 .0 ., .10?;2PR 3 54 4' ).00 00 o.00000 ?.I000023 .1604? 3. 4.(l .00?1890 563.?e .00210 .00280 2.2000023 .1604? 2.14 3.77 .'0?144 561.93 .0017? .0028 2.2000023 .1604? 4.29 2.P6 , 6022076 558.5t .0009A .00276 2.20000?3 .16042 t.43 0.iO .;022?R3 540.03 0.00000 0.00000 2.2000023 .16042 8.S7 0.') .C022835 54,.00 0.OoO0 0.00000 2.20000?3 .1604? 10.71 0.11 .1022839 40,0) 0.00000 0.00000 ?.2000023 .1604? 12.86 0.1)i .Q022835 541.00 0.O0000 0.00000 2.2000023 .16042 15.01 O.11( .OU2i35 c 40.00 0.00000 0.00000 2.2000023 .1604? 17.14 0. .0 .022935 543.0n 0.00000 0.00000 2.?0000?3 .1604? 19.;9 0.V .00?2235 540.()0 0.00000 0.00000 2.20000?3 .16042 21.43 0.3 .002283 3 94.C O 0.000 0 0.00000 2.2000023 .1604? 23.57 0.50 . 0?54?b.O0 0.00000 0.OuO00 2.2600023 .1604? 25.71 O.3 .P02?H35 54r.00 0.00000 0.00000 2.2000023 .1604? 27.A6 0. n .00??.3n 541.0f 0.00000 0.00000 2.20000?3 .1604? 30.O0 .'0 .°002?83 5(,.O0 0.00000 0.00000 2.20000

73

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CIPCtIMFERENTIALLY-AVEPAGED PARAMETFRS

NP RADIUS MACH NO. TEMP. INTENSITY FPEQUEhCY

1 .0001 1.9662 2.2955 .66906E-12 0.

2 .1000 1.966? 2.2955 .?4773E-06 3.3 .2000 1.966? 2.2955 .95416E-08 C.4 .3000 1.966f, ?.2951 .2134E-04 7.

5 .4000 1.91R2 2.2398 .16103F+05 241f.6 .500O 1.?27k 1.o)6 9 8 .17198E+08 2595R.

7 *01" *18At9 1.3452 .51u43F+04 16407.

8 .7f00 .0028 I.u583 .398P5E-04 4377.9 A(Oi .0019 1.;777 .41234E-06 524.

10 .9 00 .1277 1.2755 .11304E+04 5139.11 1.01C. .A929 I.,q?57 .1] 9P4E+08 12312.

12 1.1000 1.5573 P.1133 .?QO16E.08 5707.13 ].2on0 1.723? ?.?014 .4??13F.08 ?S95.14 1.3000 1.7745 ?.?247 .40008E*08 1676.

15 1.4000 1.7964 2.?343 .1582.fl 1326.

16 1.9"l I . ?4 ? .2367 .4?91RE*O6 1313.17 1. AlOf' 1.7963 ?.?339 .396?4F+OR 1513.

If 1.7000 1.7761 ?2?55 .43543r 08 1888.19 1.8000 1.7230 ?.2014 .30032F+08 2593.

20 1.9000 1.55P9 2.1139 .?4184E OA 4755.21 2.0000 .q9 I1.P57 .14303E08 R933.22 ?.I000 .1275 1.?751 .19046E+04 3436.

23 2.200 .0029 I.,G(7 .19514E-04 733.

WARNING - NO. OF TOIRNING POINTS IS GREATER THAN ? AT

KA= 1 X= .07292 ITH= 10 THFTA= 110.00 NTP= 3

WARNING - NO. OF TU NING POINTS IS GREATER THAN 2 AT

KA= I X= .07292 ITH= 11 THETA= 120.00 NTP= 3

WARNING - Nn. OF TItJNING POINTS IS GREATFP THAN 2 AT

KA= I X= .07292 ITH: 12 THETA= 130.00 NTP: 3

WARNING - NO. OF TURNING POINTS IS GREATEP THAN 2 ATKA= 1 X= .07292 ITH= 13 THETA= 140.00 NTP= 3

WARNING - NO. OF TUPNINr, POINT; IS GPEATFP THAri ? AT

KA= I X: .07292 ITH= 14 THETA= 150.00 NTP= 3

WARNING - NO. OF TURNING POINTS IS GREATER THAN ? ATKA= I X= .0729? ITH= 15 THETA= 160.00 NTP= 3

74

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~(I)= .07P9 1181( I)= .?~rA99E+? I FtA( 1)= .?419E+01 (IAV(,( I) I=I 47.5S1 UMAX( 1)= 2199.46

4APNINr, NO. OF TI)PNING PO~t4TS IS GPFATFP THAN ? AT-(A= ? XZ .09187 ITH= 10 THFTA= 110.00 N\TP= 3 - - - -

WAPNING -NO.-OF TURNING POINTS IS GREATER THAN 2 AT -_ ___

'(At 2 Y= .09187 ITH= 11 THFTA= 120.00 NTPw 3

.ARN1NG -NO. OF TURPNING POINT~S IS r,PFATFP THAN P ATK=P X= .091B7. ITH= 12 THETA= 130.00 NTP=2______

4ARMING_ -t.NO.-OE IUPtlIJC2POWtTS 15 CPEATEP THAN.? AT _________________

KA= 2 X= .OQ4IR7 ITH= 13 THETA= 1140.00 NIP= 3

4APNING - NO. OF TUPNING POI'!TS IS cPFATFP THAN P AT

)KA= _2_. X=- I3...J 14_ T,4LTA _ 15J.0f -.-- NP= I

X(2) ogi w0'l1 II?)= *.t3ASF.21 FM( 2)= P?QF-01~

14A P N I N- NO.. OF TIJPN I N G PFO~iTS IS GPFATE0 THAN?. AT __ ___________________

KA= 3 x= .!1l75 ITH= 10 THETA= 1l.o1. NTPz 3

4APtIING - NO. OF TII HINr, POP'TS IS GPEATEP THAtL > AT-- X=- __I ITN LiA4E1A ?0 NIP= 3

-ANN NO. OF TOPN.ING POITS IS GPEATEQ THAN 2 AT __ ___

KA= I X= .11975 ITH= 12 THFIA= vlo.uyu NTP= 3

WAPNING -NO. OF T11PNIN6 POITS IS GPFATFR THAN ? ATKA 3 -X=. .11575--. IIH= 13 THETA= 14U.00 LTP3 ____ __3_ ______

WAPNING -NO. OF TOPNING POINTS IS GREATER THAN 2 AT___________KA . X2 .11575 ITHo 14 THETA= 19r.eo NTPm 3

(3)= .1157 1J81( 3)= .2A.1Q2E+21 FM~( 3)= .?66'F*I01 UAVG( 31= 1674.56 UMAX( 3)= 2199.45

WAPNING -NO. OF TI)RNIN(G POINTS IS GREA7ER THAN ' ATK(A 4 _ X= .1458.3-- 1THM 1 THETA= 11C.a5~ T. ____________

WARNING---NO. OF -TURNING.POINJTS. IS-GEATER THAN 2 AT.- -____________

KM4 X& .14SA3 ITHm 11 THETA= 120.00 NTP= 3

75

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1-- - - --.--.- - - - -~----.__ ____ __ - --.--------.---.---

4- 0

cc N N NN

%I Ii z zz< I) <<< t< 1 <9

4: < 4fm< T< m < i

0C z

+' 4-

II Im n I M. I I- J) 0 L ,1o

o.a aa CA 0 a4- 4-4- I-I- ~ ) 4- 1

2~~~ Z 2Z

4 c cc Z N N oc

C)1

41X Ifi .11 a '1 0:11 411 a. 11

< < <. < 4 <U . 41 LLU ~ ~ ~ N VUL UL UL

a a a a a6

Page 92: OH AIRCRAFT ENGINE GROUP F/6 20/1 292 HIGH VELOCITY ...2" 11* v o~ftz j & nr, source locamzw amu 2 reductionw task 2a., supplement ... lia r78aeg324 high velocity jet noise source

C (, il PAGE I I

COMP(ITATInN OF AEPO-ACOwSrIC PPoPERTIES OF S4PPP&S5Op NOZZLES

CASE NO. I CPR 7-TU)RF AP=?.3 rOZ7LE - VJ=2?O0 FPS - TTJ=1600 nEG-P

AXIAL LOCATTO. .?91h7 (X/OFO = 4.00W0)

M P ANGLE I ()ONSITY TEMP. U/UPEF TIPR.INT. P/DFN

I .00001 i.C.C 2106.11 ,01046R 1177.91 .95756 .016P .000101 .00001 13.0 ?116.11 .301046q 1177.9j .95756 .00168 .000101 rooo1l ?0no0 ?106.1l .001046P 1177.9t ,q5756 .0016P .000101 .00001 3G.00 ?106.11 .o010468 1177.-' .95756 .01(8 .00010? *,)07?Q O.CO ?079.7G .rO105l] 1 °.73 .94555 .05657 .100002 .03729 1j.00 2079.72 .010550 11 8.73 .94556 .0565H .10000? ,007?9 ?.50 ?079.7? ..)010550 1168.73 .94556 .05658 .A000? ,c072 30.C0 ?)79.7 o,01I0551 116,.73 ,94555 .0565H .100003 .0145H n.fl.0 Q1,4.79 .o01077f, 1144.?9 .9694 ,0H7?9 .200003 "14q A

7,S' C094.74 .L010776 1144?7 .9r69? .0,472 *200O03 .3145 1g.00 1994.77 .^010776 1144.28 .90t94 .OR73 .200003 .01458 ?2.50 1994.73 .010776 144.,7 .90692 .08730 .200n03 .01459 30.00 19o4.77 .01776 1144.28 .90694 .08730 .200oo4 .o21A8 9.0" 183R.10 .0011099 1111.11 .P3571 .114?9 .300004 *fl19 7.10 1939.13 .0011094 111100? .83572 .11436 .300004 .021H' 15.On 138.^4 .nol109q 1 11.97 .83568 .11431 .300004 ..?lq ??.9C 183.,6 .0ol00q ll'.95 *A3569 .11432 .3nO004 ,cAR 33.00 1837.QQ .00111o 1110.92 ,H3566 .1143? .300005 .02917 (.00 l6(1.57 .(0114P9 1073.31 .72817 .1315P .400005 .r2917 6.0) 1601.44 .uO1149 173.23 .72811 .13160 .40000S .0?517 12.00 16C1.33 .'011491 1j7 3.07 .72804 .13166 .400005 .m2917 18 .0oj 1601.6? .1011493 1372.85 .7279? .13172 .400001 .C?917 14.O1 1600.7' .01141)6 1,72.64 .72778 .13176 .400005 .2917 30.00 100.6k .3011496 157?.58 .72776 .13178 .40006 .03640 0.00 12?0.70 .601159 1.31.04 .59 .46 .13? 5 .5n0006 .03646 6.00 1299.61 .C011)63 1,;30.74 .59(43 .1326S .500no6 .03641 1P.30 126.97 .-011975 129.74 .5896R .13295 .500006 .(3646 18.0 1295.36 .01198 I (?P.56 .58895 .13329 .500006 .03646 24.0) 1?Q4.41 .,0011 q 1027.64 .58851 .13355 .500006 .03646 30.00 1293.49 .r012004 1027.?0 .58p10 .13363 .500l07 .04c7; 0.0 9ROls ..01?487 9P7.46 .44565 .11324 .600007 .04375 5.00 978.?1 soOI?St2 986,?8 .44475 .1136? .600007 .34371 10.30 973.63 .0 1?537 991,54 .44267 .1146? .600007 .14475 1C.,) 967.6? .001584 979.89 .43994 .11590 .600007 04375 20.o 941.3 00l7636 975.87 .43710 .11703 .600007 J437S 25.00 956.95 .0012673 972.9) .4350R .11782 .600007 .1437g 30.0r 955.55 .00)?6m5 972.08 *43445 .1181? .600008 .05104 0.00 758.09 .0012799 963.41 .34467 .06822 .700009 .1;104 5.00 751.56 .0012834 96"*A1 .34170 .07114 .700008 05104 10.00 733.93 .n01P2Q8 953.80 .33369 .07705 .700008 .05104 15.00 710.9 .0011064 943.H4 .32285 .0W25? .700008 .05104 ?0.00 6A6.08 .0013216 933.04 .31193 .08631 .70000s .05104 25.00 66R.47 .,013335 9?4.72 .3o393 .0884.3 .700008 .05134 10.00 662. c7 . 013379 9?1.6R .3c101 .GI 811 .700009 .05A33 -'.00 7gS8A5 .0012799 9A3.41 .34'465 .96817 .80009 .05833 4.29 745.61 .n012839 Q60.44 .33930 .07124 HO0009 .0933 .57 710.47 .001?950 952.16 .3230? .07635 ,P00009 . 115?33 12.94 I58.39 .1I?1 939.74 .?q934 .07855 .n Ano

77

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8 **~ PAGE- 12

COMPITATInN OF AERO-ACOIISTIC PrWPERTIFb OF SIUPPPESSOlP NOZZLES

CASE NO. I CPn 7-TIIHF AR=?.3 NOZZLE - VJ=2?00 FPS - TTJ=160O fE(,-P

AXIAL LOCATIONI .29167 (X/DEQ= 4.0000, l

M P ANGLF I) OE-NSITY TEMP. W/UkEF TUPH.INT. P/LAiQ

9 .ncA33 17.14 5Q7*g .(013330 92590) .27183 .07582 .,0009 A05833 ?1.43 540.35 C0O1531 ,11.P9 .246b7 *06p14 tl00009 *m5p31 ?5.71 40R.87 .0013676 9(1.61 .?,682 .C57)q .800009 .(5833 30.00 483.69 .001372P dg9F,. .21991 .05027 .8000010 .16 6 c (.00 (8OC.9 .C01?4mi7 c,97.45 .44561 .113?1 .9000010 .06563 4.?9 958.94 .001?541 c83.5 *43599 .11533 .9000010 .061 4.57 k98 .41; oI Y?6? 971.57 *40849 .II9? .900010 .06563 12.86 805.40 .001283 4 553.39 .36618 .11906 .,000010 . )6S63 17.14 6Q2. 79 . 01244 931.09 1 31498 .1124R .9000

10 .^65(,3 ?1.43 579.98 .101'541 91, .63 *?6369 .r9745 ., 0O0010 .06563 25.71 492.43 .0013716 iQc.03 .22389 .0715R .9(00010 .0656 30 .00 4-,44 0 1375f, 8Q6,38 .?086 .03069 .9000011 0f7292 2.00 1298.64 .u011960 1031.04 .59044 .13253 1.000011 *37?<? 3.75 1278.97 .0011997 1027.8! .5950 .135PA 1.00000II .C729? 7.50 1213.17 .0012120 1(17.42 .55158 .142P7 1.0000011 .2729: 11.25 1o,9.9? .0012334 99973 .5u459 .1400 1.0000011 .07292 15.0c 977.73 .0012630 47t,3? .44453 .14727 1.0000011 .'7?9? )A.75 8?.45 .001?980 053.00 .37712 .13134 1.00000II .C7?? ??.50 6H6.,)0 n 0 1V3 9?6.50 .31190 .11965 1.n000011 .)729? ?6.25 576.o? .00135)6 912.95 .26189 .0888? .QA00011 .072?Q 3).00 533.54 .0013553 q09.83 .24,;8 .04985 1.00001? .80?1 0.00 1601.50 .0011489 1073.30 .72813 .13157 1.10000I? .ORO?! 3.75 1577.02 . 0115? I 6.60 .717v1 .13788 I.10000I? 0RC?l 7.0 1503.70 .00116a5 1658.63 .68367 .15133 1.IC0000

I .I071 11.25 1383.35 .,011948 1,4 .71 .62895 .1633 1 .1000012 .8021 15.00 1219.62 .001?135 1.:161l .55451 .16798 1.100001? .0021 18.75 108.14 .0012507 g985*g .46745 .1613- 1.1000012 0R0?] ??. 0 838.)3 .001?285 956.97 .38102 .14139 1.10000I? C08021 26.25 68R,35 .013137 o03s.r .31296 .10494 1.1000012 .08021 30.0C 6?9.41 .0013?01 934.09 .28617 .05050 1.10000I3 .)8750 -. 00 138.0('4 .00 1199 1111.01 .83568 .1148 1 .2000013 .08750 3.33 1817.98 .,.Oll35 1107.37 .82656 .1 226 1.?n00013 .3P750 6.67 1756 .9 .0011?41 10Q6.90 .798? .14180 1.2000013 .0 750 10.00 16S3.41 .;011412 I80.52 .75174 .]611) 1.2000011 ,oP790 13.33 1507.73 .n011642 1059.16 .68550 .17533 1.2000013 to8750 16.67 1326.82 .001193? 1033.45 .60325 .18014 1.2000013 .087q0 20.60 1116.- .001??H7 1003.54 .50778 .17240 1,2000013 n87;0 23.33 Q93.38 .0012641 975.46 .41619 .15031 1.2000013 .oA750 ?.67 760.19 .001?286 958.20 .34563 .11C59 1.2000013 .°3R7C0 3C.00 6q9.78 r o01?926 153.93 .31816 .0394? 1.2000014 .,947q j.00 10)4.74 C0010776 1144.?8 .90693 .087? 1.3(900014 ,9479 3.33 1974.9 .0010822 1139.4' *89795 .1015 1.3000014 oQ479 6.67 1914.12 .0011951 112.76 .87023 .)255 1.300001' .)947

9 10.00 l607.q< .0011154 11g,55? .8182 .15554 1.3000

14 .9479 13.33 152.47 .0011410 1(R0.71 .7t131 .17#63 1.300014 .09 474 1 .67 1451.76 .011721 10?.06 .66005 .18673 1.3000014 .09479 20.0 121Ip1? .01209 I01).96 .59383 .1H?0' 1.30000

78

.~ -NM I,

Page 94: OH AIRCRAFT ENGINE GROUP F/6 20/1 292 HIGH VELOCITY ...2" 11* v o~ftz j & nr, source locamzw amu 2 reductionw task 2a., supplement ... lia r78aeg324 high velocity jet noise source

. *** AI ,f P 1(E 3

COMPrATI hI OF AF RO-AC O(T TIC PROPEPT IES OF c(jPPPF SSO NOZZLFS

CASE NO' 1 CPD 7-TUHF AP=?.3 N077LF - VJ=2200 FP - TTJ=iO0 fE0-P

AXIAL LOCATIO! = .29167 (K/oEO 4.O00CS)

m P ANGLE U DFNSITY TEMP. U/LJREF TUPH. INT. P/DEO

14 *0947C 26.(7 799.20 00?757 o6f.18 .36291 .11775 1.30000

14 .nQ479 30.00 7?5.24 .00183l 96(,.9R .32973 .004c'5 1.30000

19 .10?CA ,.ur ?079.69 .c010551 1 19.7? .94554 .)56q 1.40000

i5 .1020A 3 . o ?064.c3 .001059f 1 163.69 .93843 .0785% 1.40000

15 .?029 6. -3 ?315.26 .0010726 1 4q.t, r 91b26 .10976 1.4 0u0

15 *1020P 9.tort 19?2.f4 .l0109 2 3 IIPP.86 *87687 .14000 1.4C0(,

iS .10209 1?.o 179.20 *,]011168 11(4.R .818? *16.? 1.40000

15 .1o2,c? 15.00 1624.99 .0011454 1(:76.54 .73881 .18425 1.4OOO

15 .10?)R 1.30 1411.t4 .00117PR lC46.1 .6418] .19010 1.40000

15 .1008 2 ?.IC 172.£ .*30?lHl V,12.27 .53311 .18135 1.4000

1 .i020 ?4.(' q4?.79 .C01?? q79°?3 .42 86 .1 569C ).41000

15 .02oR ?7.09 766.69 .'01?97? 9c 7.97 .4888H .1114? 1.40000

15 .1021R 3).00 698.15 .-oO1?4 7 95?.41 .3174? .0400? 1.400;0

th .10935 1.3 ?l16.fP .f010469 1177.98 .95755 .00131 1.50000

16 .1093P 3.0C ? 0P9.Q? .((Iq 1 172.16 .95)20 .069H2 1.50000

16 .1093H 6.0( 2039.21 O0019665 1156.?3 .92714 .10518 1.5000

16 .l093A J.0 194R.1? ro0108H? 1133.09 .98573 .1377? 1.5000

16 .I9.1p 12. 0 1910.36 .011151 110c. A' .82319 .16-,71 1 . 0

16 .1093l 15.0" 16?3.35 .011464 1.75,63 .73 9 u 7 .18414 1.5'000

16 .103R 18.0c 13q.64 .c011837 1041.70 .63363 .188gp 1.50000

16 .i09lp 21.03 1 .R .0012300 cO?.51 .51644 .1796? 1.S(000

16 .10q3p 24.00 aR.64 .O01?9oA (,7?.5 .404,j3 .15401 1.50000

16 .1091A 27.00 6Q8.70 . 13180 9,., 3 .31767 .1I21? 1.500

16 .10939 3K.00 (?4.17 .3013288 9?7.94 .?8379 .n515p 1.50000

17 .116(7 0 0 2079.64 .0018851 116H.69 .94553 .05661 1.60090

17 .IIrr7 ?.73 ?064 .6 .(,010594 11 3.3 .93t81 .07639 1.60000

17 .)16A7 ;.Z p0ol.'A .101#717 l1o.53 .91790 .10564 1.60000

17 .11667 .IR 1917.3? .01.)906 1131.61 .9R9H? .13436 4 6( f0

17 .11 A 7 1,).14 IR15.35 .0011144 l110.47 .PS3 6 .15995 1.60000

17 .11667 13.f4 16c0.35 .8011426 1079.16 .75034 .17H34 1.60000

17 .1167 1.3f, lI4S.IQ .001 176 1)47.S? .65716 .18636 1.60000

17 .11667 19.0 I 1l0.13 °1012? 1 1 Iu.6 1 .5502c .18208 1 .6000

17 .11667 21.R? 965.46 .001275? 866.93 .4389; .1525 l.o000

17 .11617 ?4.8c 743.4 .0013331 ?4.94 .33806 .13778 1.60000

17 .1f6.7 ?7.?7 -7 R.H .001374) bQ8.93 .263) .4 q31 1.60000

17 .11667 3).00 515.41 .0013875 hAR.71 .2434 .05403 1.6000

1 .1286 0 .8C 1994.5 .6010777 1144.15 .*Q(685 .(;H734 1.70000

18 *1?396 2.73 1977.29 .coloiq 11lq.8S S9s99q .09823 1.70000

IR .2396 5.45> 194.r1 .01(q31 11?7.67 .87477 .12066 1.70000

18 .12396 4.IR 1831.25 .rOllll6 1109.29 .83259 .144,; 1.70000

1 .1?396 1 q IIo195.34 .30l1174 |0.6.06 .77080 .16479 1.700C0

18 .12196 1.6 4 1516.33 .0Ol16C,4 1'8.07 .*6941 .17735 1.70000

19 .1?o6 16.36, l30?.9 .IjOlC4 3 lU?3.87 .59137 .17q31 1.70000

18 .1239 19.09 1057.75 .8012592 974.*Q .48091 .16939 1.70000

I .12396 21.82 pjm|H9 .40?3264 9?Q.7s .3718 .14918 1.70000

19 .I ?39f 24.55 606.74 .-013991 q98.3? .?75H6 .12107 1.70000

18 .12396 27.27 4 20? .0O14540 9R.04 .20551 .08595 1.70000

1 IC9 .00 o A 3'IQ;).4? (101470c) 3A.3 . 17842 n497? I. 7nn0

79

Page 95: OH AIRCRAFT ENGINE GROUP F/6 20/1 292 HIGH VELOCITY ...2" 11* v o~ftz j & nr, source locamzw amu 2 reductionw task 2a., supplement ... lia r78aeg324 high velocity jet noise source

* * , A ; * * * PACE 14

COmd !'T MTY0 OV AF-O-ACOIucTJC PROPFRTIIFS OF SUPPEFSSOP NOZZLES

CA'-F- tr , I CPO 7-TIURF AP=2.3 NOZZLE - VJ=2?00 FPS - TTJ=1600 1Er.-P

AXIt1 LOCATTO( - .29167 (x/OEO = 4.000U0)

L. 4'-(A F ki (f 1U4 TS IY TEMP. (i/UPEF I 1PH . I r, T . /

11 31 ?1- ).(1 1 -47. 39 0r l l: 1 1Cr II1 .4+2 .H3539 . )1I4iq I. o C, o0

1 .1 31?" ?.5u 19H?..44 .4011136 1 I( 7.3 .R2768 .120C71 .H0 001q Q . 3 1? ;,L .,1 1 7 H. ,(4 c I I ??

P I n #,p .P? h 424 . I I JEc4 . Hon0o

19 .131?E 7.' 1l6" 1.4? .001137q 1vlC3.7 7 .76447 .1oq07 1.p00001,4 . 1 7 1 I. I 15 c .14 .(0 1 1 1 7 1 ()-4 .P .7 ¢7A 7 . 1 ()?(,4 .1 t , 0

19 13 1 1.QI 137.4O . ? 14 .463 7 1 b.1b431 p.2100I Q 13 12- 1h n P,,!6. . ,0 7u o I I - 97 .'54 864 . It H l . ln10C,0

19 .1 31? , 17.50 . 97.5c4 .C0764 96f-.03 .4553;4 .16935 1.000019 131q 2? .cc 7P7..? *0134?9 'l,'.?4 .3 19 .142491 . 0000

19 .1 1? 22.5 ( c, 3 .76 .6c14217

7.3r .,9,6 .12005 1. 60(01 1 31?5 2L*. f 41 .22 .315017 ?1.12 .1 c696 .09427 I.0 G01 . 31?£ ?7.5( 316 ).P9 .C01"%lqc 74iti . * 144 (,M .0,659 I 1000I9 .I 13? 3 ;.'C 273 .4 .'01L-;771 701.9p .12433 .04087 1.00020 .1 3R5 30^ 15Q .74 .;011s16 17 .72 .7?6PA .13194 1.,OO002 I .3#4 ?.4 0 15,79.89 .(0115E E R 167.T7 .7183 .135A? .9,00020 .IIA54 ).(]C 15?3.?2 .r)011644 Lrti.99 .69256 .14?77 .q000020 .1 3854 1.C 14?c. ?7 .1011 H' lu'-*4.23 .64703 .1Sq4 1.n0 00

?0 1 385o, 1'.CU 1301 .'5 .'1012052 123.13 q190 .16?? I.90DO0?0 I 3954 12.50 1136.77 .01?401 7 Q 3.H4 L)516H. .1577 1.93000

2o .I 30A4 15.03 454 .012H96 956.17 .43399 .14R44 1.'LC0002o I 39r,4 17.c5'" 7',6.15 . 0 3 3 '11.3Y, .34834 .13,"5£ 1oci()o20 .I 3A4 ?1.0 5r,.jop .90143?C. 961.07 .76601 .1154 1 .l000,c .1 3854 ?.r, 'c.?.4? .'Ol5?3n 0: c.65 .19342 .393,? 1.90000

20 . 3R94 ?.C ?(96.cs .0 1613? 7(4.3C .13496 .07079 .,010000 . 384 ?7°.5 ?0R.(1 .,1670 734.4A .9457 .OZ+P2, .o0 0

20 .13854 3 .(. 174.2 . .% 16907 725.87 .O7023 .03019 .9000021 .145R3 C0.9 0 1?H7.4( .'012r,7q I. ).R4 3H*583, .13417 ?. O00021 .1 49A1 e.31 1?73.23 .' 0lI C9l Q 1 1 765 - .1353? 2. 0000?l .I 4,5 R 1-2I1 ., .:II.,01 1 109.39 .5I535 .13771 .1 )00021 .1 4p 3 f,.9? 11L3 .PC .00124,0 ')/.4 .51840 .13956 ?.00000?1 .14583 9.21 1'33.50 .;; I671 L73.0P .469809 .13924 2.0000021 .1453 11.54 9)05 .49R .0013049 44.9Q .41169 .13506 2.00000

21 .14593 1339,

764.63 .'nI139 41 ).74 .34764 .1264r) 2.0000021 .1483 11.15 619.74 .0 14161 7 .74 .?8177 .11370 ?.;0300

2 14511 11 .4 f, 4P4 I.43 .'014913 ?o.87 .?]H 9 .09777 2.0000021 .14583 2).77 3S7 .91 .00 1 S764 7H2.20 .16273 .001? 2.00000

P1 .1 4q3 23.0 24 .57 .0166A64 710.96 .11574 .0236 P.(1000

21 .14;5H3 ?5.3 175.01 .C01751 704.5A .07957 .0494 2.00000

?I .14c;%43 27.69 121.b4 .C01R"79 6p?.03 .05530 .030o? ?.00000

?21 .145A3 31.00 1G1 .49 . 101 ?4q 675 .7)

.04614 .02011 2.000 00?? .15313 ".f0 937.77 .'312946 2c,?.4 R .42637 .11903 2.100002? .15313 2.14 24.9W .. 1)00127 94(c*49 .42G3 .11979 2.10000

2? .I5s13 44.29 89qH7.8l 0 01 . l r , 1 ct. 1 4 .4 035 .1143 2.1 t00

2 .15111 11.43 282.08 . 013.10 9

426.59 .37640 .11719, 2.10000

2? .1"313 8.57 749.c54 .C 011,)A 906.R0 .34079 .1 14f-0 ?.10002? .19313 I).71 656.99 .101399 H1.41 .29870 .1070 2.10000

2? .15313 1 ? 55A c-6.37 .')01 448 1.2 .2519, .1000R 2.1(000;22 .1513 1.00 I I n .o 4r4. . "01 0 R 9 17.r1 .2i3667 .o HI) Ir, p. I ronn

80

Page 96: OH AIRCRAFT ENGINE GROUP F/6 20/1 292 HIGH VELOCITY ...2" 11* v o~ftz j & nr, source locamzw amu 2 reductionw task 2a., supplement ... lia r78aeg324 high velocity jet noise source

I * N C, p P A * *IGF 15

COMPIITATION 0v

AFwO-ACOLISTIC PROPFPTIFS OF ,ijPPPFSSO8 N077LES

CASF NO, I rP 7-1'HF AP=2.3 Nn77LF - V.J=?200 FPS - ITJ=1600 DEC-P

AxIAL LOrATION .29167 (X/DFQ = 4.0000,')

m p ASLE U )FNJTY TEOP. I J/IPEF T08. 11.. I /[TFO

2? .131' 17.14 357.45 ..,0 1 r- 777 781.57 .16%252 .n7(34 2.100902? .19313 34.24 ?70.S4 .1"01 f543 7ss,. 19 .1"3u1 .158pk ?.100q0?2 .1531' ?1.4'3 187.>? .*%17346 71., .l..H,,f7 .C461 2.1oo2? .15313 ?3.'7 1"7.85 .01B14 ? 7 4 . 7 .0,27, .i373F .10'0?? 131C33 ?5.7 1 c 3. 7 ' .01P P 4 t-i4 I,.. 17 .C'.2"- .02,75 f.1000022 .15313 27.66 64.47 .3018'13 f- lk.4 , .029 31 .017p6 2.100o02? .15,31' 30. C, ( 3.60 . 0144 4 3&.1 .*1 ,7 .3197 2.140023 .16042 c .0 613.13 .001419- p,-.70 *?7H7 .q41 ?.?500023 .16042 2.14 603.k2 .',014?4? i .?74? , .6 T0 ?.200n0P3 .1604P 4.*q 575 . .0143H7 857.,.6 .*?61(- I *(1 C6 ?.?nO00?3 .1604? 6.43 9 10. 11 .0 146?2? H4?*91 .?4#1.- J f88 ?.?00()023 .1604? 8.57 472.73 .0 14Q7 9 -. 72 *?14.3 .CI() ? .?0000P3 6t)04? 1.71 406.7P .00)14.)g 0.? . 5 .077'10 ?. n 0 023 .1I04? I1.RO 317. 135 .,01594? 773.46 .15 3?,4 ..,)087 ?.2000?3 164? 15.iY 258.33 *1655R 744.6A .1 2246, .95929 2.20000?3 .1604? 17.14 ?C6.7? .r'017?38 715.3r .04399 .04904 2.20000?3 .1604? IO.?Q 15?.?l A3017Cl5 t6.64 .069? .03RR7 2.2000023 . I F042 ?lI. 43 1.-7.77 ., o18P H(,R I Cp .049010 .285 2.2000CP3 .1,04? ?I. 7 73.44 .101Q367 f 6 .7 .0333Q .0214q 2.2A00023 .1604? 2'5.71 48.2? . 01 P64 617.66 .02193 .014R4 2.2000023 .1604? 27.46 1.74 n0O?0367 ,5.4? .01443 .O09p 2.?O0023 .1604? 33.33 25.54 .30204P4 61.86 .(1161 .0065C 2.2,100024 .1677! ).00 37 . 3f .n)1177c 741.48 .162415 .r64P7 ?.3o000?4 .1',771 2.00 391.6! .10 142?4 77Q.?5 .15986 .0h431 2.30000?i. .1h771 4.00 35.%9 .110 7 772.74 .15258 .06210 ?.3(i,0?4 .1771 6.00 310.'i .0016176 762?.?6 .1409 .0599| 2.300C024 .16771 4

.CO 277.37 .30164P1 748.17 .12597 •O.)q52 2.3000?4 .16771 1. or ?40.00 .(-A1,6 731.32 .10912 .35086 2.300o024 .16771 12 .if 200.67 . 01731? 712.27 .09123 .04'.05 2.30,o024 .16771 14.0O 161. P7 .0017H?O 691I .95 .07360 .03854 2.300?4 .1I6771 16.nuO 1?6.)) .'0 1,367 67137 .05734 .03189 .300C(024 .16771 1 .00 4.96 .3O0 1,9 f-1I.4l .0431H .02550 2.300 024 .16771 ? 3 .Cu 6 R. tn 7 .0019496 532.46 .03122 .01 Q4 2.3000024 .16771 22.00 47.91 .0020038 515.35 .02178 .01446 2.3000024 .16771 ? .0 3?.?7 .0 ?,' 31 6o0.63

, .01467 .1')31 2.3l000

24 .16771 ?F, .0 ?rl.97 . )2C.04 7 54 8 , 0 c ,954 .0070, 2. -31)0o0?4 .16771 ?.%1 13.73 .0()21I 51.3? .006?, 00464 2.o000024 .16771 3c.0 1 0.4 .O?9 57P.8( .004'4' .00 P7 2.300)025 .17r.0 1.00 3F86.1? . 1749 704,8, ti) .IH4e',,' . ,') ?.40000PC .17CO ?.0 Iq2.5 .30 1753 703.08 .0"', .0 Ail 2 ).4800025 .1750 4.0') 173.41 .-,07sf 1 68.2p .07 ' .( 37t.1 2.4000025 . 17;0 6. 3 158,. 16 .00178f60 8. IQ .0, P .C' Th? ,.4000025 .17500 .O0 140.63 .00191 34 f871. ) 4' 12 .2 4 ()o00025 .17500 13.00 ?Op.R .C00146 7 * *. .3 .f 2.PI C04002 . 7 3 12.09 o01 .8* .001q45 14.15 .,,4, .1.,,..8 ?.400O025 .17500 1 .03 78.44 .101)27. &3(). 77 . f 3'- 'U7( 2.40000? .17500 1 .03 ,Q .4 .01-714 ,25.4, . 4 .1.) r 2.400002r-, 7c;03 1.0 I I0 44 .Pn 1 r5 f .I I. .R Ih, . 1l h14) 2.40000O

I8

Page 97: OH AIRCRAFT ENGINE GROUP F/6 20/1 292 HIGH VELOCITY ...2" 11* v o~ftz j & nr, source locamzw amu 2 reductionw task 2a., supplement ... lia r78aeg324 high velocity jet noise source

COMPrIATION OF AFPO-ACOUISTIC PPO(PEPT7FS OF SUPPPFSSORP N07ZLES

CASE NO4' I (00f 7-TfRf7 Ac-=. 3 t(,7L( - VJ=;2?Oo FPS -TTJ=I 600 0-

AXIAL LOC.ATION = .29167 IX/IOFo= '4.000'jj)

Ni p A'4 L E D E 1 1S IT Y T FM P . [),'uPFF T 0PS H I r r . E~ I-

?c; .1759 ?9.t,0 () I 1.1I4 .3,2c)(4' .99(04 . 014 1 H *0 Q()4 ?2. 0025; .17900 ? ? . 1, ; ?1.1I? *002996l7 'P7 . -5 .0 09t0 .0169,4 2.4.00 , CP5 .1750,0 ?4.nQ 11.77 . 0?1344 ',77.71 P.32 ~4~ .4.0000P95 .79t)0 26 . 0 46 *0?21 -31, F3 9 ? .0039w4 .0C33z 2.'4f00025 .1 7900 2-. "C 5.41 .C 0 ?1 11 , I 5'.'- C i 1.-40:4 .0023? 2 . 00C0?C5 I17530 30G. 00 41' .IH 02 1 77 63 6 '4 .00 1 o0 *00lq2 ?..G90 026 (I I18229 .091 '6 .6-, *j0 O 6 1 '.56 7 6 394/I0 .020'1 2. )0 00?2( .1 229 1.417 05. .") 0 1 13 1 t14 . 56 *03 69 .0(20 ?c 2 2.560 002 6. .R2? 1. 7 c p0. L4 *0 1 4 p17 -,41.64 *0IToHl .0 1 37& 2.0 0 )0

?26) I *1? ? 5.6 ? 74 . f6' C, I -AL7 137 .0 ? .*3 3)(, *0 1 .6 ; 50 0 026 I1F?,9 7 ; 'Co' p. 4) !0 1 9 -' I r .* 67 .03-,19 o.I (-q7 ?.bo000?6 .1 p? . 37 57.l .I r01 97Th' P-4 *Q025~p .011; ,r , r.50o26 . 1224 11 . ?R 47.6 .'-c; (iCi004m L' 1.0 G *(166 .01303 2. ,0 0 11?6 .1 8?2; 3. 1? 38.?Q oU020337 f(00.33 .0141 0 1 C.-7 ?.590000P6 I R;??Q 10 9 2. 6c, !l( .21)(o1 c 57 .41 .(11 3'4 H .0-7q 2. )0 01026 .1 8? 16.P7 ?2. 17 .'0C4 ~ .1 .10O', .0063 t2.10000?6 .lR??91 1o.75 16.1"3 .0 ?9 ')R .00/2?9 ("1", -4 P.500A

6 .18229 22.62 1 1.1)4 (002 1 c;" 573'1 . 0 0 )7 .00O 2.156 D0 0026l I FA229 ??.59' 7.44 .P2171, f 567*9 03 3 .0 f?' 2.5-0C0( 026 .1?? ?.3 7 4.70 .0?5 5691) ; s,1.6 3 .021 .lI 0 0?' 2 .P5 0 ( r0260 ?I,?' 2.29 ?. ' P ( .0?;, 1 lb S7 F, f *'"013) .0 1 72? .- 02 6 .1R229 ? a. I? I.o6 .0? 21 - 7.0?*7 ) .07 .015 7.0

?6 .1 A21) 390. 00 1.1 ~ .022 17 4 6! 0r* *9)5 4 .0)0H2? .5002 7 1 R058 0 36.196 JL ? 0 4 11 4.1 .Ic' 01(40 .00971 ? . t'00902 7 *14; '. 1 A7 3 3k . ~ ?'9 .3 . 7 *Z ISOt .0P 0695,7 25.?7 .19~ C.7 33'? .00o 0.0 1524 .097 .00

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82

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-A 094 292 GENERAL ELECTRIC CO CINCINNATI OH AIRCRAFT ENGINE GROUP F/S 20/1HIGH VELOCITY JET NOISE SOURCE LOCATION AND REDUCTION. TASK 2 S-ETC(U)

MAY 78 P R GLIEBE OOT-OS-30034UNCLASSIFIED R78AE6324 FAA-RD-76-79-2A NL

2 2 flflfflflfflflfEmEE..h.---- Eu--II-IIIEE.I

Page 99: OH AIRCRAFT ENGINE GROUP F/6 20/1 292 HIGH VELOCITY ...2" 11* v o~ftz j & nr, source locamzw amu 2 reductionw task 2a., supplement ... lia r78aeg324 high velocity jet noise source

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Page 100: OH AIRCRAFT ENGINE GROUP F/6 20/1 292 HIGH VELOCITY ...2" 11* v o~ftz j & nr, source locamzw amu 2 reductionw task 2a., supplement ... lia r78aeg324 high velocity jet noise source

** M* P G 6 DAGE 17

COMPUTATION OF AFRO-ACOUSTIC PROPERTIES OF SUPPPESSOR NOZZLES

CASE NO. I CPP 7-TURE AR=2.3 NOZZLE - VJ=200 FPS - TTJ=1600 DEG-R

AXIAL LOCATION 1.16667 (X/DFO 15.99999)

M p ANGLE U DENSITY TEMP. tL/tIREF TURH.INT. H/DEU

I .00r31 0.3C 1231.43 .Ao1??99 1(02.6p .563(,6 .00079 .000161 ,.003 I.00 1238.43 .,012299 1 .6? .563S6 .00J79 .000161 .0000i ?-.01 1718.43 .*1l12?99 .0?.6? .56306 .00079 .000161 .00001 30.o0 1?38.43 .O012299 V O?.6? .563C6 .00079 .00016? .01167 0.c- 1?36.41 .001?310 1C01.65 .56215 .019q9 .160002 .. 07 0OGO 1236.43 .0012310 1001.65 .56215 .01960 .160002 .0iM67 ?.00 1736.44 .0012310 1001,66 .56216 .01961 .160002 .01167 36.00 1236.44 .001231) I'01.66 .5621b .,01960 .160003 .02333 0.00 1?30.gr .C012345 998R 596 .02794 .3?0003 .^2333 7. 1 30 .89 .01235 998 .7 .55963 o02794 .3?0003 .02113 15.00 1?10.qo .0012345 996.8A .55964 .02797 .320003 .02333 22,S¢ 1?30.Q2 .012345 998.88 .55965 .02797 .320003 .C?313 R.03 ?30.98 .nDI0344 99A.9', 55967 .,279A .3?00O4 .3500 0.UO 1I?.34 .uO124C; 994.04 .55529 o03476 .4P0004 .03500 7.S0 1??1.47 .o0l404 9Q4.07 .55535 .03477 .410004 .3500 15.oo 1?1.3Q .0012404 994.C7 .55S32 .03482 .4t0004 .1350 1 ?2.SO 121.41 .901?404 994,6 .55532 .034A9 .4A0004 .0350c 30.00 1??1.32 .0012404 994,97 .5552A .03491 .480noS .#-4667 0.00 IP6.68 .012491 96f6*99 .54672 .04115 .640005 .n4667 6.01 1?-06.94 .901 493 9P7.0? .54875 .04119 .640005 .f4667 I?.or 1206.9A .0012493 9P7.05 .54876 .04135 .640005 .!4667 ]8.00 1206.86 ."01749? 98707 .54871 .04154 .640005 .04667 ?4.00 1?06.74 .001249? 987.Jn .54865 .04169 .640005 .04667 30.o 1206.84 .001?492 9P7.12 .54870 .04170 .640006 .05833 ,.o00 I67.62 .A012613 977.66 .93996 .04768 .800006 .0583 6.06 1167.6? .,n1?61; 977.69 .53996 .04783 .800006 *.5833 I2ooo 11A7.26 .CO?611 977.75 .S3980 .04814 .800006 .C5831 1 .0) 1187.;6 .')01?610 977.86 .53971 .0450 .800006 .".811 24.00 I]87.59 .001?6)a 977.9A .53972 .04878 .800006 .05833 30.00 1187.07 .1012608 978.03 .53971 .04888 .800007 o07000 0.00 1162.27 .0012765 966.0] .52843 .0546C .960007 .07000 5.00 116?.31 .0012764 966.08 .52845 .05478 .960007 .07000 10.o0 1161.97 .001276? 966.24 .52830 .055?0 .960007 .07000 5.O0C 1161.4A .6012759 966,44 052808 .05571 .960007 07000 20.00 ill.p8 .001?755 966.7o .,52799 .056)8 .960007 .07000 25.00 1160.97 .001753 966.86 .52784 .05648 .960007 .07000 30.00 1160.9? .001?75? 966.94 .52782 .05655 .9f0008 .08167 0.00 1110.21 .0012946 (?.48 .51386 .06181 1.120008 .08167 5.00 ll0.r .0012944 952.61 .51378 .06208 1.120008 .08167 10.00 1129.59 .0012940 95?.9? .51358 .06?7P 1.1?0008 .08167 15.O0 1128.75 0001?935 "53.32 .51320 .06347 1.1?0008 .08167 20.00 1128.C7 .001292s 993.79 .51289 .06411 1,12000A .68167 ?5.00 1127o3 .1012924 4c4.10 .5125A .06453 1.1?000R .08167 3;).00 1 12 7 .u7 .001?923 954.20 .51243 .06465 1.120009 .09333 O0 1060.2? .001315; 917.34 .49570 .06894 1.2po009 .39131 4.29 1090.O0 .0013153 937.5i .49561 .06919 1,280009 .1933 * 87 1069.36 .0013147 917.9| .495?9 .06987 1.28000

9 ."9111 IP.Af 1066.1 tnlfllq 9 18~.44 .494A? .i#7A7; 1.Pp00

84

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i!

m* G4( R * PAGF 18

COMPUTATION OF AERO-ACOUSTIC PROPERTIES OF StoPPRFsSOR NO7ZLES

CASE NO. I CPD 7-TIuIF AR=?.3 N'OZZLE - VJ=??00 FPS TTJ=1600 DEG-P

AXIAL LOCATIONJ 1.16667 (X/IFO = 15.999991

M p ANGLE U DENSITY TEMP. U/UREF T(IRB.INT. k/DEQ

9 .'9333 17.14 1087.31 .,0131?9 939.17 .49436 .07151 1.280009 .09333 21.43 10 8 6 .v4 .C0131?? 939.73 .49378 .07208 1.280009 .0933 25.71 1685.25 .d001lll 94,1.17 .4934? .07242 I.?0009 *09131 11.06 104.88 .6013113 94Z,31 .49325 .07253 1.2PO00

10 .10900 ).00 1042.41 .0013387 9?1.08 .47394 .07553 1.4400010 .10500 4.29 1041.87 .0013385 921.26 .47369 .07585 1.4400010 .10r00 8*57 1040.72 .0013376 921i.88 .47317 .07667 1.4400010 .10500 12.86 1038.96 .0013363 972,76 .47237 .C7767 1.4400010 .10 17.14 1017.13 f:01334R 9-3.7 .47154 .07854 1.44000

10 .10500 ?1.41 1035.17 P0O13336 9?4,64 ,47u65 .07914 1.4400010 .10500 25.71 1033.91 .,'0133?6 9?5.3n .47007 .07946 1.4400010 .10500 39.00 1333.26 .t013323 (05.51 .46978 .07954 1.4400011 .11667 0.00 985.99 .001164? 903.86 .44829 .0810c; 1.6000011 .11667 3.7r 985.47 .0013639 91)4.08 .44805 .08133 I.bAO00II .11667 7.0. QA4.n9 .0013629 904.73 .44742 .08206 1.6000011 .11667 11.25 981.9? .001361 905.7D .44644 .08298 1.60000

II .11667 15.00 979.34 .0613599 906.P4 .44526 0h3b4 1.6000011 .11667 18.7, 976.76 C-013SPO 90M.O(t .44409 .08448 1.6000011 .11667 ??.S 974.34 .1013 69 9g,8q .44299 C-84RA 1.6000011 .11667 26.25 972.7C .01359r 9(9.66 .44225 .08504 1.O000011 .11667 31.00 972.31 .1013551 90919S .44207 .08510 1.600001? .12833 5.00 921.76 .0013917 l85,9 .41909 .68510 1.760001? .17833 3.75 9?0.97 .0011q]4 RR6.24 .41873 .08538 1.760001? .12833 7.5c 91.A91 .001390I 887.0? .41779 .08hI0 1.7600012 .12831 11.2S 915.85 .fo13883 8A8.21 .41640 .08701 1.760001? .12833 15.00 91?.? .00138l 889,63 .41475 .0871i 1.7600012 .12I33 18,75 906.30 .E013A38 "1.05 ,41297 .08835 1.760401? .12833 22.50 904.86 .0013AO 892.7 ,41140 .08861 1.76001? .1?833 76.75 90?.56 .C013807 k93.09 41036 .08866 1.7600012 .12833 30.00 901.71 .001380! 893.38 .40997 .08866 1.7600013 .14000 9'.01 850.11 .0014216 867.36 .38651 .08730 1.9?00013 .14000 3.33 849.,7 .0014212 867,60 .38617 .08750 1.9200013 .14000 6.67 847.30 .0014?01 868*33 .38523 .08A05 1.9?00013 .14000 10.00 843.77 .00141F3 869.38 .38363 .08876 1.9200013 .14000 13.33 839.44 .0014161 870e7? .38166 .08943 1.9200013 .14000 16.67 834.79 .0014138 (72.18 37954 .08988 1,9200013 .14000 ?0000 R30,35 .001411S 873.58 .37753 .Oq09 1.9200013 .14000 23.33 826.85, .0014096 874,76 .37593 .09009 1.9200013 .14000 26.67 824.45 .0014084 875,51 .37484 .09001 1.9?00013 ,14000 30.00 823.73 .0014079 875080 .3745? .08998 1.9200014 .15167 0.00 772.49 .0014541 #47,97 .3512? .08750 2.uO001. .15167 3.33 771.38 .3014538 848,19 .35072 .08767 2.0800014 .15167 6o67 768.55 MO14Sq 848.91 -34943 .08813 2.0800014 .15167 10.00 764.35 .0014506 850.6 *34752 .08871 2.0800014 .15167 13.33 759.01 .1014482 851,47 .34509 .08918 2.0800014 .15167 16.67 7c3.47 .0014455 853.05 .34257 .08943 2.0800014 .15167 20.00 747.99 .0014430 854,52 .34008 .08941 2.0800014 15167 71.11 741.77 .Oflt44f(Q 85.79 .1A14 .A8Ql 7.nAAAA

85

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M * * q , 8 * * * PAGE 1q

COMPUTATION OF AERO-ACOUSTIC PROPERTIES OF SUPPRESSOR NOZZLES

CASE NO. I CPD 7-TUJRE AR=2o3 NOZZLE - VJ=2200 FPS - TTJ=1600 DEG-R

AXIAL LOCATION = 1.16667 (X/DEQ = 15.99999)

M p ANGLE U DENSITY TEMP. U/UREF TUPR.INTo R/DEO

14 .1S167 ?6*67 740.7S ,014395 856.58 .33679 .08902 2,0800014 .15167 3G.00 739.65 .3014391 8S6.84 .33629 .08893 2.08000i5 .16333 A.0c 690.4? *0014A9R 827.68 .31391 0h564 2.24000is .16333 3*0l 689.59 .0014894 kW7.88 .31353 .08575 2.2400015 .16313 6.00 6R6.8) .0014885 R28.43 .31226 .08603 2.2400015 .16333 9.00 682,73 .0014868 829.35 .31041 .08638 2.2400015 .16333 12.00 677.69 P"O14P46 813.56 .30812 .08667 2.24000 !15 .16333 15.00 671.85 u014827 831,90 .305,t6 .08677 2.24000Is .16333 18.00 665,83 .0014799 P33.24 .30272 .08666 2.24000

15 .16331 pIOG 6A0.62 .0014779 814o56 .30035 .08640 2,24000r .16313 ?4.00 6-6.?7 .0014757 835.59 .?983A .08605 2.2400015 .16133 279CC 693.$1 .9014745 H36,28 .29712 .08578 2.2400015 .16333 30.00 6c?.68 .0014740 836,57 o29675 08568 2.2400016 .17500 0.00 606.1 .9015289 906s53 .27589 0A184 2,4000016 .17900 3.01 605.99 .015285 8n6.75 .27552 .08193 2.4000016 .17500 6.0 602*Q9 .0015276 807.20 .27411 .08208 2.4000016 .17500 9.O() %98.56 .,015?60 908.06 .27214 .08227 2.4000016 .17500 12.00 592.66 .,015?40 809.09 .26946 08234 2.4000016 .17500 15.00 SP6.40 .0015?16 810.36 .26661 .08?5 2.4000016 *17500 18.00 579,P3 .0015192 811.65 .26362 0b193 2.4000016 .17500 21.0C 574.10 .0015169 81?.0q .26097 .0814q 2.4000016 .17500 24.00 569.29 .0015150 813.93 .25883 .08101 2.4000016 .17500 27.^C 566.13 .0015138 814,56 .25740 .08062 2.4000016 .17500 30.00 565.13 .0015133 814,81 .25694 .08049 2.4000017 .18667 0.00 524.23 .0015714 794,69 .23834 .07644 2.5600017 18667 2.73 573,45 .1015711 794.83 .23799 .07647 2.5600017 .18667 9.45 5?0,84 .00157,5 785.15 .23680 .07651 2.5600017 .18667 8.18 516.92 .015693 785.74 .235C2 .07655 2.5600017 .18667 10.91 511.73 .0015678 786.50 .23266 .07649 2.5600017 .18667 13.64 505.65 .0015661 787.38 .22990 .07627 2.5600017 .18667 16.36 499.45 .0015640 788.42 .22708 .07592 2.5600017 .18667 19.09 493.33 .0015619 789.45 .22430 .07540 2.5600017 .18667 71,8? 487.93 Q01561 0 790,4? .22184 .07493 2.5600017 .18667 24.59 483.66 ,00155s5 791.20 .?1990 .074?9 2.5600017 .18667 27.27 491.',2 .9019574 791.74 .21870 .0739? 2.5600017 .18667 30.00 4A0.13 .0015570 791.94 .21829 .07378 2.5600018 .19833 0,00 444.5 .0016173 76?.41 .2u26 .06978 2.7?00018 .19833 2.73 444.,6 .0016)71 762,53 .20190 .06978 2e72000IR .19P33 5.45 ,441.44 .0016166 762.75 .20070 .06974 2.7?00018 .19833 8.18 437,39 .0016157 763.17 .19886 .06964 2.7200018 .19833 191 432.15 .r016145 763.74 .19648 .06942 2.7?00018 .19831 13,64 426.10 .0016130 764,46 .19373 .06906 2.7200018 .19833 16.36 419.72 .0016113 765.27 .19083 .06854 2.7?00018 .19833 19.cq 413*45 .C016095 766.10 .18798 .06790 2.7200018 ,19P13 ?1.82 407.9q .0016078 766o94 I855 .06722 2.7200018 019A13 74,9 403.63 .0016064 767.62 .18352 .06660 2,7200018 .19833 27.?7 400.90 .0016054 768.08 .18227 .06616 2.7?00018 .198A1 l0.A 39qq.q .n16n51 768.? .IIS? .6600 2.7?n00

86

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M c, G PAGE 20

COMPUTATION OF AERO-ACOUSTIC PROPERTIES OF SUPPRESSOR NOZZLES

CASE NOO I CRD 7-T(IRE AR=2.3 NOZZLE - VJ=2200 FPS - TTJ=1600 OES-P

AXIAL LOCATION = 1.16667 (X/DEO = 15099999)

M p ANGLE iJ DENSITY TEMP. LI/UREF TUP8.INT. R/DEQ

19 .1(100 0.00 370.73 .n01666? 740.06 .16855 .0 62 28 2.8800019 .21000 2.50 370.1 .0016661 7 4 u.1l .16823 .06225 2.8809019 .21000 5.00 367.92 .0016658 740.23 .16728 .06?17 2.8800019 .21000 7.50 364.58 .0016653 740,45 .16576 .06200 2.8800019 .?IO00 10.0c 360.11 .0016647 740,74 .16373 .0617? 2.6900019 .21000 12.53 354.93 C0016637 741.15 .16137 .06133 2.8800019 .plo00 15.00 340.35 .0016625 741.68 .15883 .06081 2.8800019 .21000 17.r0 343.58 .0016613 742,23 .15621 .06017 2.8800019 .21000 20.00 338,1i ,0016599 742.84 .15376 .05948 2.8800019 .21000 22.5o 333.44 .1016587 743,4- .15160 .05879 2.8800019 .?1000 25.4c 3?9.79 .0016576 743.89 .14994 .05821 2.8800019 .01000 27.50 327,48 .0016569 744.21 .14889 .05781 2.8800019 .?1000 39.0 326.69 .0016566 744.32 .14853 .05767 2.8800020 .22167 0.01 3 3.31 .0017173 718e03 .13790 .05436 3.04000?0 .22167 2.50 302.60 .0017173 718902 .13758 .05431 3.0400020 .22167 5.00 300.64 .001717? 718.06 .13669 .05418 3.04000?0 .?2167 7.50 297.45 .0017171 71A.13 .13524 .05394 3.0400020 ,22167 10.00 293.36 .0017167 718.31 .13338 .05359 3.0400020 .22167 12.c0 P8.49 .0017161 718.52 .13116 .05312 3.04000?0 .22167 IS9.0 283.14 .0017155 718.8i .12873 .0525? 3.0400020 .22167 17.50 277.74 .0017145 719.18 .12628 .05183 3.0400020 .22167 20.00 272.60 .0017136 719.6,) .12394 .0S109 3.0400020 .?P167 22.50 268.15 .C017129 720.03 .12192 .05038 3.0400020 .22167 25.00 264.66 .0017117 72C.40 ,12033 .04977 3,0400020 22167 27 .SG 262.47 .0017110 720,66 .11933 .04937 3.0400020 .22167 30.0C 261.72 .0017108 72(.75 .11899 .04922 3.0400021 .23333 0.00 243.54 .r017699 696.68 .11073 .04640 3.2000021 .73333 2.31 ?43.02 .0017700 696.67 .11049 .04635 3.2000021 .23333 4.62 241.46 .0017701 696.63 .10978 .04621 3.200n021 .23333 6.92 239.06 .0017701 696.62 .IL869 .04598 3.2000021 .03333 9.23 ?35.R0 .0017701 696.61 .10721 .04564 3.2000021 .23333 11.54 231.86 .0017701 696,62 .1054? .04520 3.000021 .?3334 13.85 ?27.5? .0017649 696.7, .10344 .04466 3.2000021 .23333 16.15 222.94 .0017695 696.83 .10136 .04404 3.2000021 .23313 18.46 218.46 .0017690 697.04 .09932 .04336 3.?0000?1 .23333 20.77 214.31 .0017681 697,31 .09744 904268 3.2000021 .23333 23.08 210.74 .0017676 697.58 .09582 s04204 3.2000021 .73333 25.38 208.uo .0017670 697.83 .09457 .04152 3.2000021 .23331 27.69 206.28 .C017666 698.00 .09379 .04118 3.2000021 .23333 30.00 705.69 .0017664 698.07 .09352 .04106 3.2000022 .04500 0.00 191.94 .008229 676,44 .08727 .03874 3.3600022 .24500 2.14 191.56 .0018230 676.41 .08709 .03869 3.3600022 .24500 4.29 190O.4 .6018231 676,39 .08657 .03857 3.36000P2 .74500 6.43 188.54 .0018234 676.25 .08572 .03835 3.3600022 .24500 8.57 186.04 .001A237 676.15 .08458 .03804 3.3600022 .24500 10.71 183.*C .0018243 676.04 .08320 .03765 3.360022 .74500 12.86 179.58 .V018242 675.97 .08165 .03718 3.3600000 .245rn 15. An 17.91 .nnlAP4P 67S.94 .07998 .f3664 1.36onn

87

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*0* M G p *p * PAGF 21

COMPUTATION OF AERO-ACOUSTIC PROPERTIES OF SUPPRESSOR NOZZLES

CASF NO. I CPO 7-TURF AR=2.3 NOZ7LE - VJ=2?O0 FPS - TTJ=1600 OEG-R

AXIAL LOCATION = 1.16667 (X/DEO = 19099999)

M P ANGLE U OENSITY TEMP. U/UPEF TURH.INT, R/DEU

2? .?4500 17.14 172.18 *0019241 675,97 .07828 .03605 3.36000

2? .24500 19.29 168.57 .0018239 676.07 .07664 .03544 3.3E(000P? .?45)0 ?1.43 165.28 .0018239 676.21 .07515 .03484 3.36000?? .7490 23.57 162.49 o01A231 676.37 .07388 .03430 3.360102? ,P4S00 2S.71 160.36 .0018226 676.53 .07291 .03386 3.3600022 .74500 ?7.86 19Q.03 .0018223 676.64 .07231 V03358 3.36000P? .?4S00 3J.00 158.5p oJ0182?? 676,69 ,C7210 .03348 3.3600023 .75667 C.00 14H.97 .0019751 697.61 .06755 .03165 3,b?00023 ?25667 2.14 14P.24 .001875? 6.75M .06740 .03160 3.5200023 .75667 4.?9 147..6 °90|1794 697,48 ,06695 .03147 3.52000Z3 .75667 6.43 145.67 .-019759 697.34 *C6623 .03126 3.5200023 .?5667 8.57 143,13 .0018764 657.16 .06526 .03096 3.52000?3 .?5667 11.71 140.94 .0018769 696.97 .06408 .03058 3.5?00023 ,?c667 12.86 138,'1 .001R774 6S6.79 .06275 .03013 3.5200023 .25667 15.10 134.87 .001877A 6;6.66 .0613? .0296? 3.5200023 .25667 17.14 131.67 .0018780 696.58 .09987 .02906 3.5200023 .75667 19.2c 128.97 .0018780 696.57 0it46 .02849 3.5200023 .25667 21.43 1?5.74 .0018779 696.6? .05717 .02794 3.5?00023 .5667 ?3.97 1?3,33 .00177A 66.71 .05607 .02744 3,5?000?3 .25667 25.71 121.49 .0018774 696,l .05524 .02704 3.5200023 .25667 27.S6 120.34 .0018771 6;6,89 .05471 .02678 3.5200023 .75667 30.O0 l19.9 .t018771 b66.92 .05453 .02669 3.5200074 .26833 0.00 112.PR .-019255 64().39 .05132 .02529 3.6800024 .26833 2.03 112.64 .0019256 640.34 .05121 .02526 3.6800024 .?6831 4 .00 111.93 .1019261 64n.?4 .05089 .02515 3.680024 .?6833 6.00 110.78 .C019264 640.08 .05037 .02497 3,6800024 .6833 8.o 109.?? .0019271 639.87 .04966 .02473 3.6800024 .26833 Ioo0 107.3? .0019278 639,64 .04879 .0244? 3.6800024 .76833 1?.0G 105.13 .0019285 639.41 .04780 *02406 3.6A00024 .26833 14.00 102.75 .0019291 639.19 .04672 .02364 3.6800024 .26833 16.00 100.27 .GO19296 639.0? .04559 .02319 3.68000?4 .26A33 18.0c 97.79 .0019300 638.90 .04446 .02272 3.*6000?4 .26R33 ?0.00 95,44 ,U019367 638.84 .04339 .02224 3.6A00024 .26833 22.00 93.31 .V019302 638.83 .04242 .02179 3.6F00024 .6833 24.00 Q1.51 .0019301 638.87 .04161 .0213q 3.6800024 .6833 ?6.00 90.16 .0019299 638.92 .04099 .02108 3.68000?4 .?6833 28.00 89.31 .001929R 638.97 .04060 .02088 3.6R(00?4 .76813 10.03 89.o12 0019297 638.99 .04047 .02081 3.6800029 .8o00 0.00 84.19 .0019734 6?4.84 .03828 .01978 3.8400025 .2800,) 2.00 84.00 .0019735 624.80 .03819 .01975 3.8400029 .78000 4.00 93,41 .001973Q t?46.9 .03793 .01966 3.8400025 .28000 6.00 A2.50 .001974S 624.51 .03751 .01950 3.8400025 .po00 .00 81.24 .0019752 624.28 .03694 .019 R 3.8400025 .28000 110I% 79.70 .O19761 624.01 .03624 .o01901 3.8400025 .28000 1?.0' 77.94 .1'019769 6)3,74 .03544 .01868 3.840007r .2800 14.00 76.11 o 019777 623.4R .03456 .0183? 3.84000PC .28000 16.0( 74.1f .001q785 623.25 .03365 .0179? 3.84000PS .2R)Alnfl I1.0n 71.Q9 .OA1979. 61 .AA .0173 .n1701 3.H4A00

88

ILk ...

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*** M G P **. PAGE 22

COMPUTATION OF AERO-ACOUSTYC PROPERTIES OF SUPPRESSOR NOZZLES

CASE NO* I CPn 7-TURE A=2o3 N0Z7LE - VJ=?200 FPS - TTJ=1600 nEG-R

AXIAL LOCATION = 1.16667 (X/DEO 15o9999q)

M P ANGLF ) DENSITY TEMP. U/UREF TUPR.INT. R/DEQ

?5 .P8010 20000 70. '7 *0019744 h?2,97 .03186 .01710 3.8400025 .78000 22.00 68,33 .nOlQ79g 6?2.91 .03107 .01671 3.b4000P5 .P8000 24.0,0 A6.7 .0019795 6?2,91 .03040 .01637 3.84000P5 .28000 76.nC 6S.76 .0019795 6?2.93 .02990 .01611 3.84000? .8000 ?8.i! 65..;6 .0019794 62P.96 .02958 .01593 3.8400025 .po00 3f,.OC A4.t3 .j019791 622,97 ,02947 .01587 3.84000?6 729107 0.00 61.6.1 vO?0180 61l.14 .02802 .01514 4.0000026 .P9167 1.n7 61.'i0 .C020181 611.0 .02796 .01512 4.00000P6 .09167 3.75 61.11 .,020185 610.9c. .02778 .01505 4.00000P6 .?4167 5.6P 60.46 .10?0190 61).73 .02749 .01493 4.0000026 .Q167 7.1;5. 595. . .020197 610.5? .02709 .01476 4o00000P6 .79167 9.17 ;8.ol .0020206 64|.26 .02660 .01455 4,00000P6 .29167 11.?9 c7.26 .00?021% 6f9*99 .02603 .01431 4.0000026 .29167 13.12 55,p .j020224 609.71 .02540 .01403 4.00000P6 .?9167 15.' 54.41 .0?0?32 609.46 .02474 .01373 4.0000026 .79167 16.87 52.91 .uO70?40 6(Q.24 .02466 .01341 4.00000?6 ,79167 18.75 c1.44 .0020245 609.06 .021339 .01308 4,.00000?6 .?9167 2C.6? 50.59 .0020?49 buso99 .02276 .01?77 4o0000026 P9167 22.50 48.81 .602025? 608.88 .02219 .01247 4.0000026 .Pql67 24.37 47.76 .0020252 608.86 .02172 .01222 4.00000?6 .29167 ?6.?s 46.98 .(02025? 668.86 .02136 .01202 4.0000026 ?9167 28.12 46.4 .C02025? 608.87 .02114 .01189 4.0000026 P9167 '1100 46.37 .11020757 6C9.8 .02106 .01185 4.0000027 30333 0.00 44.28 .0020598 598.94 .02013 .01135 4.1600027 .10333 1.87 44.1F .1020589 598.90 .02009 .01133 4.1600077 .30333 3.75 43.A8 .0020592 sq8.Ro .01995 .011?7 4.1600027 .30333 S.7? 43.39 .000598 59R.63 .01973 .01117 4.1600027 .30333 7.50 42.72 .0020606 598.42 .01942 .01103 4.1600027 .10333 c,37 41.89 .0020614 598.16 .01904 .01086 4.1600027 .30333 11.25 40.93 .0020624 bq7,BA .01861 .01066 4.16000P7 .30333 13.17 19.87 *0020634 597,6f .01813 .01043 4.16000?7 .30333 lb.00 38.74 .0020643 597.34 .01761 .01018 4.1600027 .30333 16.A7 37.5R .O0020651 597.10 .01709 .00992 4.16000P7 .30333 l8.79 36.45 .0020658 596.91 .01657 .00966 4.16000P7 .30133 20.6? 35.37 .002066? 596.77 .01608 .0094v 4.1600027 .30333 22.50 34.41 .0020665 596,69 .01564 .00916 4.1600027 030333 24.37 33.60 .0020667 596.65 .01528 .00895 4.1600027 .30333 26.25 32.99 60020667 596.63 .01500 .00879 4.16000P7 .00333 ?8.12 32.61 .3020667 596.64 .01482 .00869 4.1600027 .10333 30.00 32.48 .0020667 596.64 .01477 .00865 4.16000?8 .11500 C.oC 31.7 .0020955 588.45 .01419 .00832 4.3200028 .31500 1.76 31.15 .0020956 588.42 .01416 .00831 4.3200078 .11500 3.93 30.95 .0020959 588.34 .01407 .00827 4.3200078 .1I00 5.29 30.63 .0020964 588.19 .01392 .00819 4.3200028 .31900 7.06 30.1P .0020970 588.01 .01372 .008l 4.3200078 .31900 8.82 29.6? .0020978 587.78 .01347 .00798 4.320002A .31500 10.9 214.97 .00?0987 587.54 .01317 .00783 4.3?000PA .I I fl IP.5 28.2P ..P0;096 57.28 .n184 .OA767 4.3Pfnn

89

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V) C L. 0 0,~

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Cc 4 %c

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Page 108: OH AIRCRAFT ENGINE GROUP F/6 20/1 292 HIGH VELOCITY ...2" 11* v o~ftz j & nr, source locamzw amu 2 reductionw task 2a., supplement ... lia r78aeg324 high velocity jet noise source

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Page 109: OH AIRCRAFT ENGINE GROUP F/6 20/1 292 HIGH VELOCITY ...2" 11* v o~ftz j & nr, source locamzw amu 2 reductionw task 2a., supplement ... lia r78aeg324 high velocity jet noise source

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Page 110: OH AIRCRAFT ENGINE GROUP F/6 20/1 292 HIGH VELOCITY ...2" 11* v o~ftz j & nr, source locamzw amu 2 reductionw task 2a., supplement ... lia r78aeg324 high velocity jet noise source

. . 1. . . . . . . . . . . . . . ... . .

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94

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APPENDIX D

PROGRAM SOURCE CODE LISTING

This appendix contains the FORTRAN IV source code listing for the

aeroacoustic prediction model, suitable for running on the CDC 7600 computer.The listing of subroutines is in alphabetical order, as follows:

1. MAIN Program (MGB)2. ARRCCOS3. ATMOS4. CRD5. ERF6. LSPFIT7. OUTPUT9. PNLC9. SHOCK10. SLICE11. TPNLC

95

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Page 113: OH AIRCRAFT ENGINE GROUP F/6 20/1 292 HIGH VELOCITY ...2" 11* v o~ftz j & nr, source locamzw amu 2 reductionw task 2a., supplement ... lia r78aeg324 high velocity jet noise source

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Page 114: OH AIRCRAFT ENGINE GROUP F/6 20/1 292 HIGH VELOCITY ...2" 11* v o~ftz j & nr, source locamzw amu 2 reductionw task 2a., supplement ... lia r78aeg324 high velocity jet noise source

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REFERENCES

1. Lee, R., Kendall, R.M., et al: "Research Investigation of the Generationand Suppression of Jet Noise," General Electric Company ContractorReport No. NOAS 59-6160-C, January 1961.

2. Grose, R.D., and Kendall, R.M: "Theoretical Predictions of the SoundProduced by Jets Having an Arbitrary Cross Section," A.S.M.E. Symposiumon Fully Separated Flows, May 1964, pp. 58-63.

3. Mani, R. (Ed.): High Velocity Jet Noise Source Location and Reduction,Task 2 - Theoretical Developments and Basic Experiments. Contractorfinal report, FAA-RD-76-79-II, 1977.

4. Benzakein, M.J., Chen, C.Y., and Knott, P.R.: "A Computational Tech-nique for Jet Aerodynamic Noise," A.I.A.A. paper no. 71-583, June 1971.

5. Lighthill, M.J.: "On Sound Generated Aerodynamically I. General Theory,"Proc. Roy. Soc. (Lond.), vol. A211, 1952, pp. 564-587.

6. Ffowcs Williams, J.E.: The Noise from Turbulence Convected at High Speed,"Phil. Trans. Roy. Soc. (Lond.), vol. A255, 1963, pp. 469-503.

7. Jones, I.S.F.: "Aerodynamic Noise Dependent on Mean Shear," J. Fluid Mech.vol. 35, 1968, pp. 65-72.

8. Ribner, H.S.: "Quadrupole Patterns Governing the Pattern of Jet Noise,"J. Fluid Mech., vol. 38(l), 1969, pp. 1-24.

9. Knott, P.R., and Benzakein, M.J.: "Analytical and Experimental SupersonicJet Noise Research," A.I.A.A. paper no. 73-188, January 1973.

10. Moon,L.H., and Zelazny, S.W.: "Jet Noise Modeling": Experimental Studyand Model for the Noise and Turbulence Fields," A.I.A.A. paper no. 74-3,January 1974.

11. Chen, C.Y.: "A Model for Predicting Aero-Acoustic Characteristics ofCoaxial Jets," A.I.A.A. paper no. 76-4, January 1976.

12. Mani, R.: "The Influence of Jet Flow on Jet Noise; Part I. The Noiseof Unheated Jets," J. Fluid Mech. vol. 73(4), 1976, pp. 753-778.

13. Davies, P.O.A.L., Fisher, M.J., and Barratt, M.J.: "The Characteristicsof the Turbulence in the Mixing Region of a Round Jet," J. Fluid Mech.vol. 15, March 1963, pp. 337-367.

14. Harper-Bourne, M., and Fisher, M.J.: "The Noise From Shock Waves inSupersonic Jets," AGARD Conference Proceedings no. 131, 1973.

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15. Anon, "Standard Values of Atmospheric Absorption as a Function of Tempera-ture and Humidity for Use in Evaluating Aircraft Flyover Noise," SAEARP 866, 1964.

16. Deneuville, P.: "Prevision Simplifiee du Bruit d'Ondes de Choc d' un JetSupercritique de Tuyere Convergente," SNECMA YKA No. 5982/76,Oct. 11, 1976.

17. Anon, "Definitions and Procedures for Computing the Perceived NoiseLevel of Aircraft Noise," SAE ARP 865A, August 15, 1969 Revision.

18. Anon, "Noise Standards: Aircraft Type Certification," FAA Part 36,Vol. III, Appendix B, 1969.

19. Abramowitz, M., and Stegun, I.A. (Ed.): Handbook of MathematicalFunctions, National Bureau of Standards Applied Mathematics Series 55,June 1964 (1972 printing).

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