Developments in Liquid Rocket Engine Technology
Dr. Richard CohnChief, Liquid Rocket Engines Branch
Propulsion Directorate
Air Force Research [email protected]
661-275-5198
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2Air Force Materiel Command
MISSION
Deliver war-winning ...
- Technology
- Acquisition
- Test
- Sustainment
... expeditionary capabilities to the warfighter
Air Force Research Laboratory
Mission: Leading the discovery,
development and integration of
affordable warfighting
technologies for America's
aerospace forces.
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3AFRL People & Facilities
5,400 Govt Employees
3,800 On-site Contractors
10 Major R&D sites across US
40 Locations around the World
10 Technical Directorates Air Vehicles (RB)
Directed Energy (RD)
Human Effectiveness (RH) (711 HP Wing)
Information (RI)
Space Vehicles (RV)
Munitions (RW)
Materials & Manufacturing (RX)
Sensors (RY)
Propulsion (RZ)
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4Space and Missile R&D Building Block Process
6.1 6.2 6.3
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5AFRL Propulsion Directorate
Corporate
InformationContracts
Turbine Engine
Division
Engine
Components
Gas Generators
Engine Demos
IHPTET Mgt
Energy, Power &
Thermal Division
Aircraft & Missile Power
Special Power
Thermal Management
Plasma Research
Space & Missile
Propulsion Division
Aerophysics
Analysis
Engines
Materials
Motors
Operations
Propellants
Spacecraft
Aerospace
Propulsion Office
Initiates, Plans,
Promotes and
Conducts R&D
Programs in Adv
Engine Science &
Technology
FinanceCorporate
Development
Integration &
Operations Division
Administration
Civilian Personnel
Computer Support
Facility Support
Front Office Support
As of: 25 Jun 10
WPAFBEdwards AFB
DIRECTORMr. Doug Bowers
Associate DirectorEdwards Site CC
Col(S) Mike Platt
Chief Scientist Dr. Dick River
Deputy DirectorCol Bill Hack
Mr. Dave BlasiusMr. Phil MitchellMs. Cheryl SkipperMs. Mary Donohue-Perry
Mr. John FedonMr. Bill Koop
Mr. Tom Jackson
Dr. Rick Fingers
Mr. Mike Huggins
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6RZ-West Organization
INTEGRATION & OPS
DIVISION (WEST)
MR. K. VANDERDHYDE
RZO (Deputy)
FINANCE
BRANCH (WEST)
MS. RUTH DECOY
RZFB
BUSINESS
OPERATIONS
CAPT MATT
PASTEWAIT/TJ
TURNER
RZOF
INFORMATION
TECHNOLOGY
MR. CARL OUSLEY
RZOI
CHIEF OF SAFETY
MS. DEB FULLER
SE
QUALITY
ASSURANCE
TSGT TIMOTHY
ROWE
QA
EXECUTIVE
OFFICER
1ST LT ERIC MILLER
CCE
FIRST SERGEANT
TSGT CARLOS
LABRADOR
CCF (Addl Duty)
SPACE & MISSILE
PROPULSION DIVISION
MR. MIKE HUGGINS
AEROPHYSICS
DR. INGRID WYSONG
RZSA
MOTORS
CAPT KRISTEN CLARK
ENGINES
DR. RICHARD COHN
MATERIALS APPS
MAJ(S) A. DUGAS
RZSM
PROPELLANTS
DR. STEVEN SVEDJA
RZSP
SPACECRAFT
DR. JAMES HAAS
RZSS
EXPERIMENTAL DEMO
MS. JULIE CARLILE
RZSO
PAYOFF STUDIES
MR. ROY HILTON
RZST
CONTRACTS
MS. LUCY CASTEL
AFFTC/PK
ASSOC DIRECTOR
SITE COMMANDER
COL(S) MIKE PLATT
RZ
RZSRZ
DET 7
RZ (Edwards)Det 7 Other
RZSB
RZSE
As of: 1 Jun 09
Propulsion Directorate
Mr. DOUG BOWERS
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7RZ-West People
Civil Service
(175)
Military
(65)
On-site
Contractors
(240)
Overall
Advanced Degrees
13% PhD
11% MS
Approx. 475 on-site personnel
RZSE
Advanced Degrees
27% PhD
36% MS
5 in Student Programs
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8Edwards AFB
Edwards AFB is located about 120 miles North of LAXMap from Google Maps
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9MOJAVE
BORONHWY 58
LANCASTER
AVENUE E
HIG
HW
AY
14
LA
NC
AS
TE
R B
LV
D.
14
0th
ST
RE
ET
EA
ST
RESERVATION BOUNDARY
0 5 10
SCALE IN MILES
HWY 395
ROSAMOND BLVD.
MERCURY BLVD.
RO
CK
ET
SIT
E R
OA
D
EDWARDS AIR FORCE BASE Air Force
Research
Laboratory
Site
ROGERS
DRY LAKE
ROSAMOND
DRY LAKE
AFFTC
Edwards AFB
HWY 58
D.C.
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High Thrust Facilities
NINETEEN LIQUID ENGINE
STANDS TO 8,000,000 LBS THRUST
THIRTEEN SOLID ROCKET MOTOR
PADS TO 10,000,000 LBS THRUST
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Facilities: Bench-Scale Labs
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History
1939 Rocket research begins at Power Plant Lab, Wright Field OH
1947 Edwards AFB selected for rocket testing
1959 Rocket scientists move from WPAFB to Edwards
1997 AF labs consolidated into AFRL
Key Accomplishments
Saturn V F-1 engine development
Minuteman ICBM silo basing
XLR-129 engine (for Shuttle main engine)
Peacekeeper ICBM development
Missile defense interceptor HOVER tests
Titan IV solid rocket motor upgrade
RS-68 engine for Delta IV EELV
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AIAAs 1st Historical Aerospace Sites (2000)
1. Rocket Site2. Aerojet Pasadena, CA
3. Goddard First Auburn, MA
4. Dutch Flats San Diego, CA
5. Tranquility Base
6. Huffman Prairie, OH and Kitty Hawk, NC
Helped to Advance the Arts, sciences and technology of aeronautics and
astronautics, and promoted the
professionalism of those engaged in
these pursuits. -AIAA
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AFRL Edwards Rocket Site: LiquidRocket Technology Development
Air Force Programs
Air Force Proposed
Other Programs
X-33
XRS-2200
On-Demand Launch
(RBS)
Space Vector 1
AFRL Aerospike Tech
AFRL Thrust
Cell Program
Military Space
Plane & SOV
AFRL IPD
Concept
Engine
AFRL XLR-129
Space
Shuttle
SSME
X-15
AFRL XLR-99
RL-10
Centaur Upper Stage
CL-400 Suntan
DC-X
J2X
RS 68- A/B ARES
Four Decades of Leadership in Rocket Engine Technology
AFRL HCB
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Key Rocket Parameters
Key components of rocket engines Main Thrust Chamber Most catastrophic failures Preburner/Gas Generator Most tech challenges, harshest environment Turbopump Most likely to delay development, increase costs
Booster Engines Booster stages provide initial thrust to lift vehicles off the launch pad Booster engines require high thrust Flow-rates can exceed 1000 lbs/s of propellant
F-1 engine flow-rate ~650 gal/s 1.5 Swimming Pools/minute Upper Stages
Final thrust to transfer orbit Moderate thrust, high performance requirements
Critical parameters for rockets include Specific Impulse Thrust to weight Throttle Operability Reusability Reliability
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Differences between Rocket & Jet Engine
Rockets use pure oxygen as oxidizer Operate at significantly hotter combustion temperatures
Pumps need to operate at cryogenic conditions
Oxygen Blanching
Oxygen ignition of materials
Rockets may use liquid hydrogen as a fuel Extreme cryogenic conditions
Hydrogen embrittlement
Potentially very high pressures Can exceed 6000+ psi in some components
Extremely high heat fluxes
Operate at 100% throttle during most of mission Total operational time measured in minutes
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Comparison of Rocket and Turbojet
500,000 lbf 50,000 lbf
Power density 10X greater in rocket compared to turbojet
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Liquid Engine Branch Current Objectives
Technology focused Develop the technologies needed to develop next
generation of flight liquid rocket engines
Do not develop a solution to a particular point design but attempt to increase design space
Do develop integrated technology demonstrator engines Tools are a critical part of that mission
Systems engineering approach Both in execution and selection of technology to develop
Current focus Reusable Boost Stage Expendable Upper Stage
Future focus Reusable upper stage
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Joint government and industry effort focused on developing
affordable technologies for revolutionary, reusable and/or rapid
response military global reach capability, sustainable strategic
missiles, long life or increased maneuverability spacecraft
capability and high performance tactical missile capability
SMV/SOV
Air-to-Air Missiles
High Energy
Upper Stages
ELVs ICBMs
SLBMs Satellites
Micro-Satellites
Integrated High Payoff Rocket Propulsion Technology (IHPRPT)
Ground/Surface
Launched Missiles
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Liquid Rocket Engine Technology Efforts
Rocket Engine Technology Demonstration Programs1. IPD (Lox/LH2 Booster)
2. USET (Lox/LH2 Upper Stage)
3. Hydrocarbon Boost (Lox/RP-2 Booster)
4. 3GRB (Lox/LCH4 Booster)
Core Technology Efforts Drive towards Modeling and Simulation
Most common conference to present programs JANNAF ITAR restrictions It is open to people from academia Must be a US citizen
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1. Integrated Powerhead Demo (IPD)
Joint program between AF, NASA, and Industry Supports sortie-like launch for Operationally
Responsive Space (ORS)
Payoffs: 200 Mission Life (20X improvement) 100 MTBOH
First known full scale demonstration of Full Flow Staged Combustion Cycle in the World!
IPD Ground Engine: E1 Test Stand NASA SSC, Test
014TA: Standard Start to 85%PL, (Actual 89%PL) w/
Steady State; Test Profile SA, December 15th, 2005
IPD Ground Demonstrator Engine
installed in E1 Complex Cell 1
IPD Ground Engine: E1 Test Stand NASA SSC, Test
013TA: Standard Start to 80%PL, 87%PL w/ Short Hold;
Test Profile RA, November 10th, 2005
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IPD Program
IPD program sought to improve the nations technological capability in Liquid Hydrogen/Liquid Oxygen (LH2/LOX) booster engines
Design began by examining the failure modes of the SSME
Sought to eliminate these failures through the use of a new engine cycle
Full Flow Staged Combustion
Program executed by team consisting of: AFRL
NASA
Rocketdyne (now Pratt & Whitney Rocketdyne)
Aerojet
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Benefits Provided
Reduced Turbine temperatures
Improve turbine life and increases reliability
Eliminates of two criticality 1 failure modes
Turbopump interpropellent seal
Heat exchanger to pressurize propellant tanks.
Thermally gentle start sequence
increases turbine life
Current SOA
High Pressure LOX/LH2
Booster
Space Shuttle Main Engine
Fuel Rich Staged Combustion
Benefits of IPD Full Flow Cycle
Successful Test Program with one set of hardware
Incorporation of large amounts of Modeling and Simulation tools
Tools drive the test process
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2. Upper Stage Engine Technology (USET)
RL-10 Engine initially developed in the 1950s and first flew in 1961
RL-10 engine is currently used on both EELV
AFRL USET program seeks to allow the creation and transition of a modern upper stage engine
Focus on developing critical tools
Two contractor teams Aerojet
Northrop Grumman
All
operational
DoD
satellites
lifted by
EELV
Atlas V
Upper stage
RL10-A-4-2
Delta IV
Upper
stage
RL10-B-2
Turbopump
Assembly
Identify Issues
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USET Objective
Objective: Develop and demonstrate the next generation Model Driven Design (MDD) tools on an upper stage engine component
Selected Turbopump
Approach: Link commercial design tools with rocket specific empirical data,
rocket specific material & propellant libraries, and user defined functions
Replace targeted legacy design tools with physics based tools
Enable Multi-Disciplinary Models, Time Accurate Solutions & Interconnected Models
Reduced design time, more design iterations
Higher fidelity analysis earlier in process
Multi-disciplinary optimization
Use Tools to design validation turbopump assembly
Validation: provide sealed envelope predictions to compare with test dataModels & design tools applicable to other Liquid Boost & OTV Applications
- Range of Thrust - Range of Propellants - Range of Engine Cycles
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USET Output
Validation Turbopump
System Tool
Thrust Chamber Tools
Turbopump Tools
Modeling & Simulation
USET
Tools
Pump and Inductor Performance
Cavitation
Integrated Vibration Tool
Bearings
Turbine Performance
Axial Thrust Critical Fits Clearances
Transient
Engine Start Margin
Linked Coolant Combustion
System Sizing Tool
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USET Validation Turbopump
Challenges
Design and Fabrication of Highly Instrumented Pump
Over 100 measurements
Full shaft position measurement system
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USET AccomplishmentsAFRL Test Stand - Facility Readiness Review (FRR)
Activation with GN2 and LN2 Complete
Hydrogen Vents, Drains, and Flarestacksystem upgraded to comply with recent changes in NFPA code
Successfully passed Facility Readiness Review (FRR) Facility permitted to load Hydrogen First LH2 loaded on 2 Feb 10
Testing to complete in FY2011
Pump Supply Line
Test Stand 2A Activation
USET Validation TPA
inside of Test Skid
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USET Tool Improvement
(Pump Performance Methodology)
Description
Enables 3-D Pump Component Design & Performance Analysis Early in
Development
CFD Based Verification of Pump Efficiency, Head Coefficient, and
Cavitation
Current Methodology
Meanline Empirical Design
Limited CFD Late in Design Process
Impact
Better Performance Verification Earlier in Design Process (Fidelity Forward)
Enabled USET CavitationOptimization
Enabled Improvement of Off-Design USET Performance
Lower Test Risk
Reduced Design Iteration Late in Development
USET Improvement
3-D CFD Verification of Design Performance
CFD Based Optimization
Cavitation Performance Optimization
Assessment of Off-Design Stability and Performance Early in Design Process
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3. Hydrocarbon Boost
Hydrocarbon Boost establishes the required
tech base/knowledge base for domestic ORSC engine
Developing new Liquid Oxygen/Kerosene staged combustion engine 250k skid based brass board demo engine for simplified test stand operations
12 year development effort (2007-2019) Aerojet Prime contractor
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Hydrocarbon Boosters: State of the Industry
Increased Life + Operability + Performance =
HC Boost Demo Will Redefine Global State-of-the-Art
270
280
290
300
310
320
330
340
350
0 200,000 400,000 600,000 800,000 1,000,00 1,200,00 1,400,00 1,600,00 1,800,00 2,000,0
Thrust (Klbf)
Isp
(V
ac)
MA -5
Atlas I/II
1963
RS -27
Delta II/III
1972
H -1
Saturn I
1961
US Technology Base
Gas Generator Cycle
RD -170
Zenit
1987
F -1
Saturn V
1967
NK -33
N -1
Never Flown Russian Technology Base
Ox -Rich Stage Combustion Cycle
RD -180
Atlas V
1999
200 400 600 800 1000 1200 1400 1600 1800 2000
270
280
290
300
310
320
330
340
350
0 200,000 400,000 600,000 800,000 1,000,00 1,200,00 1,400,00 1,600,00 1,800,00 2,000,0
Thrust (Klbf)
Isp
(V
ac)
Russian Technology Base
Ox-Rich Stage Combustion Cycle
200 400 600 800 1000 1200 1400 1600 1800 2000
US Technology Base
Gas Generator Cycle
RD-170
Zenit
1987
RD-180
Atlas V
1999
RD-191
Naro-1
2009
NK-33
N-1
Never Flown
Merlin 1C (100k)
Falcon (1&9)
2008FS-27
Delta II/III
1972
MA-5
Atlas I/II
1963
H-1
Saturn I
1961
F-1
Saturn V
1967
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Program Objectives
Develop a 250K-lbf thrust, oxidizer-rich staged combustion cycle LOX/Kerosene Liquid Rocket Engine
Show scalability of technology up to very large thrust levels Develop technology to meet operability objectives Baseline fuel is advanced rocket grade kerosene Demonstrate goal achievement through testing and analysis
Isp Thrust to Weight Failure Rate Production Costs Throttleability Mean Time Between Overhauls Mean Time Between Replacement
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Vision
EngineTRL 3
Subscale /
Rig Testing
TRL 4Component
Testing
Integrated Engine
Cycle Testing (250K)
TRL 5
Systems Engineering Approach to Operational HC Engine Development
Component TRL GreenSystem TRL Purple
TRL 6
Flight weight
Engine
TRL 9Prototype Engine
Modeling, Simulation and Analysis
TRL 5
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3434
Subscale Ox-Rich Preburner Assembly
LOX Inlet
Injector
Calorimeter Chamber
Diluent Chamber
L Chamber
Instrumentation Ring
Throat
Igniter
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3535
The objectives of the test are to provide validation data for the tools used to design the hardware and evaluate the operation of the
hardware.
For each injector design evaluate:
Combustion performance via axial energy release distribution
Combustion stability characteristics
High-frequency transverse modes
Chug & longitudinal modes
Injector face, acoustic cavity, & chamber wall thermal compatibility
Steady-state temperature uniformity of preburner exhaust gas
Ignition characteristics
Start transient characteristics/low-throttle operation
Subscale ORPB Rig Test
Test Objectives
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Structural & Thermal Analysis:
Finite Element Analysis (Commercial)
Combustion device M&S design roadmap
CoDR PDR CDR
CFD Approach (Commercial)
Mixing Flow,
No Chemistry
Mixing Of Two Streams
r=r(Yi,T)
Estimate Heat
Release Profile
One Step Chemistry
-r=r(Yi,T)
pdf, Equilibrium
-r=r(f,f)
Refine Heat Release
Profile
One Step Chemistry
Multi Steps Chemistry
Reduced Mechanism
Need Test Data To
Guide CFD Model
Refine Chemistry To
Account For RP
Decomposition
Multi Steps Chemistry
Droplet Combustion (?)
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Example of CoDR Level CFD Analysis
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4. 3GRB
Advancement of the state of the art Innovative cycles/ component technologies
Pursue IHPRPT Hydrocarbon Boost Phase III and Operability Goals
Fuel Choice Rocket Grade Methane MIL-PRF-32207 is the baseline fuel
Methane has high potential as fuel for booster stage rocket engines
Database and experience on pump fed methane engines is lacking in US
AFRL to leverage existing pressure fed activities (NASA)
Develop rocket engine components Component and/or breadboard validation in laboratory
environment
No integrated demonstration
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Program Objectives
Develop component technology for a high performance next generation LOX/LCH4 liquid rocket engine
Show scalability of technology up to very large thrust levels Develop technology to meet operability objectives Baseline fuel is advanced rocket grade methane Demonstrate goal achievement through testing and analysis
Isp Thrust to Weight Failure Rate Production Costs Throttleability Mean Time Between Overhauls Mean Time Between Replacement
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3GRB Roadmap
FY 09 FY 10 FY 11 FY 12 FY 13 FY 14 FY 15
Task Order 1Aerojet
Task Order 1Pratt and Whitney
Rocketdyne
Task Order 1WASK
Initial Risk Reduction
Component Demonstration
Vision Engine
Development
Vision Engine
Development
Vision Engine
Development
Initial Risk Reduction
Task Order 2Contractor TBD
Task Order 2Contractor TBD
Task Order 3Contractor TBD
IDIQ competition
Task Order competition
Task Order competition
3 Awards Task Order 1Complete
Trade studies
Vision engine development
Technology Identification
Risk reduction
Plan 2 Awards Task Order 2 Initial Risk Reduction -- In source selection
Mitigate critical risks identified in
TO 0001 through M&S
1 Awards Task Order 3
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Staged Combustion Cycle Low Preburner Gas Temperature Assures
Long Life
Multiple Thrust Chamber Assemblies Small TCAs improve High Frequency
Combustion Stability
Center of Mass Pulled Close to Vehicle Interface
Small TCAs Lower Development and Test Costs
Compact TPA
Aerojet Vision Engine Overview
Fuel Inlet
LOX Inlet
OX Isolation
Valve
Preburner
Fuel Cooling Manifolds
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PWR Vision Engine
Expander-Heat Exchanger Cycle (Ex-Hex)
HEX reduces system pressures
Enables higher Pressure Ratio turbine
Reduces heat required to run cycle
Significantly reduces Turbopump power
Ex-Hex Eliminates PreburnerNo moisture / contaminatesEliminates drying / flushing Significantly reduces Ground-Ops
Low CH4 Hot Gas Temp
Reduced hot gas system complexity
Benign fluid environment
Improved turbine drive system life
Lower Engine pressures
Existing test facility infrastructure
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WASK Vision Engine
Staged Combustion Cycle Low Preburner Gas Temperature
Assures Long Life
Modular engine design Small TCAs Lower Development
and Test Costs
Altitude compensating nozzle
Innovative TPA Eliminates boost pumps
Single shaft
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Drive Towards Model Driven Development
There is a need to improve 30-40 year old modeling, simulation, & analysis (MS&A) tools
Existing tools old and empirically based and require hundreds of tests
Industry losing grey beards and thus design and analysis capability
Could not handle new technologies like hydrostatic bearings Current and future computational capabilities allow use of
physics-based tools to supplement testing
Testing drives the cost of rocket programs Necessary Need to be smart
Test Driven
Development
(TDD)
Model Driven
Development
(MDD)
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Preburner Research
In-House projects within RZSE Research needs identified to support external efforts
Exploratory Gain a more fundamental understanding of design space
Themis High pressure hydrocarbon propellants
LOX-RP, LOX-LCH4 Staged combustion cycles
Focus on Ox-Rich Preburner Highest component risk to Hydrocarbon Boost effort Gain understanding of preburner environment
Lack of basic understanding Not an optimization or demonstration of a single design
Encompassing approach Not a single experiment or facility Both experiments and CFD Water visualization, cryogenic cold flow, hot fire testing Provides early validation data for Hydrocarbon Boost
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Preburner Research Focus
Combustion devices are focus
Preburner is first priority
Configuration of interest is significantly different than typical rocket hot gas devices
Combustion device requires good mixing
High density diluent injection Multiple flush ports injecting the fluid
Simplification of geometry results in JICF configuration
Jet-In-Crossflow (JICF) Available literature is extensive
Most research has been done at academia
Understanding at relevant environment and integrated configuration is low
Temperature uniformity
Concentration uniformity
Flow uniformity
Injector Diluent Injection
Low MR
High T
Mixing
Tu
rbin
e
Goal: T uniformity
High MR
Low T
Supercritical Fluid Flows
Multiple Jets/Jet Systems interaction
3D configuration constrained
Extreme Pressure
High J
High RrhoReacting flows
Subsonic Flows
Penetration
Vortex Generation
Well Understood, Extensive Literature
Available
Themis Simulations
Supersonic Flows(Ramjet/ Scramjet)
AtomizationAeration of JetsResidence TimeWeber Number Relations
JICF Literature
Not capable of
comparison in
a cold flow
experiment
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Preburner Mixing ProcessesMultiple Confined Transverse Jets
Understand mixing of LOX with combustion gases From transverse jet literature
Importance of entrainment in governing jet trajectory Scaling laws, confined and unconfined
Phased research process Water-visualization facility
Explore mixing efficiency and scaling laws for relevant geometry Low-speed variable gas facility
Employ different gases to achieve relevant density ratio and mass flow ratio regime
High-pressure cold-flow facility Liquid N2 injection into He/Ar gas Supercritical fluid mixing phenomena (dilatation, transport property
variations, etc.)
Hot-fire test facility Sub-scale preburner configurations Explore combustion/mixing interactions
Tools Experimental: LDV, PLIF, flow visualization, PIV, temperature and pressure
sensors Computational: CFD and linear stability analysis
Incre
asin
g r
ele
van
ce
Decre
asin
g a
ccess
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High Performance Hydrocarbon Fuels
Develop and transition new fuels
Feedback to chemists to improve fuel performance
Tailor fuel properties Density Energy Vapor Pressure Thermal Stability
Energy density of advanced synthetic fuels offers potential for:
Use of advanced fuels as additives to improve performance for specialized missions
Improved performance for volume constrained applications
RP-1
Fuel 1
Fuel 2
Fuel 3
C* RP-1
C* Fuel 1
C* Fuel 2
C* Fuel 3
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Improve Current Fuels
RP-1, Standard
GradeTS-5 RP-2, Advanced
Grade
Led development of new grade of rocket propellant
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Thermal ManagementTranspiration Cooling
AFRL in a joint program with Northrop-Grumman and Rolls Royce Liberty Works performed some of the first experiments examining transpiration cooling in a rocket engine environment
Utilized several Lamilloy samples to determine applicability for rocket engine applications
Lamilloy currently in use for turbine applications
First application in rocket environment
Seven months from concept initiation to program completion
Demonstrated feasibility of using Lamilloy
Need to design specifically for rocket engine applications
Within experience base
Sample Lamilloy Sheet
Test Section
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Combustion Instabilities
Combustion Instabilities are a key risk to any rocket engine development program
Can be extremely destructive and can destroy the engine and the test stand
Complex interaction between many phenomena
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Materials Research
Spearheaded development of Mondaloy, a new, high strength, oxygen compatible metal
Spearheaded development of nano-aluminum which has greater strength than typical aluminum alloys
Bulging
indicates
ductile
failure mode
In both std
and NP Al
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53
Conclusions
AFRL/RZS is leading the development of the next generation of rocket engine technology
Focused efforts examining Cryo-Boost, HC Boost, and Upper Stage Rocket Propulsion
Aggressive goals lead to unique vision engines
Tool development is crucial
Developing the critical demonstration programs as well as the key underlying technologies
Improving Modeling and Simulation Tools essential for the next stage in rocket engine development
Distribution A Approved for Public Release. Distribution Unlimited. PA Clearance #10439
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