AAE 450 Spring 2008

Steven (“CJ”) Hiu 03/27/2008

“Thank You For The Memories”

MAT & FAM Coder – Structures

Composite Tanks AnalysisCAD – Tanks, Intertank Couplers, Assembly Views

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Structures main code – tanks.m

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Propellant TypePropellant Mass

Tank MaterialMax g loading

Calculate Dimensions to hold propellant volume

Spherical Tank?

L/D > 3?

Inter-Tank

Analysis

Add hoops and/or increment thicknessCalculate stage mass

Tank Buckling

& Bending

Aerodynamic Loads

Inter-stageSkirt

Analysis

Add hoops and/or increment thickness

Add stringers/hoops

NO

YES

YES

NO

FAIL PASS

PASS

COST, Dimensions, MassPASS

FAIL

FAIL

PASS

Prop Code (in MAT)

AAE 450 Spring 2008

Strength Increase – Pressurized Monocoque Flight pressure-stabilized

design 17% increase in tank strength

vs. axial buckling 30-40% increase in tank

strength vs. bending

Structures<3>

0.01 0.1 1 100.1

1

10

f(x) = 0.0604290533651837 ln(x) + 0.358329170578787

Increase in Buckling Stress Coefficient for Pressurised Cylindrical Tanks Under Bending

DCb

P/E(r/t)^2

DCb

(Nor

malized)

Design Range for vehicle

0.01 0.1 1 10 1000

0.05

0.1

0.15

0.2

0.25

Y

f z( )

X z

corr f X( )

Y( ) 0.9873

Increase in axial buckling strength versus tank internal pressure and dimensions

crPD

2ktanktan

t2D

EP

Acknowledgements Kevin Kloster, John Tsohas for help and advice Alan Schwing for tireless dedication

“He’s like some kind of…non- giving up…school guy!” – Bart Simpson

Brandon White for filling up gaps and much beer All MAT coders, especially Danielle Yaple, the Borg

Queen Everyone on the team – you’ve made it a great semester

despite the blood, sweat and tears (manly, manly tears).

AAE 450 Spring 2008 <4>Structures

Backup Slide 1 – Carbon Fiber Analysis

Structures<5>

Metallic stress

Carbon stress

metallic lining

carbon fiber sleeve

Pcontact

Pcontact

P

( ) 2 2

,1 sincontact m contact c

m m c wind c

P P r P rE t E ta

c md d

( )contact mm

m

P P rt

contact cm

c

P rt

Image: Hiu

Backup Slide 2

AAE 450 Spring 2008Structures

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Nose Cone

3rd Stage Propellant Tank

3rd Stage Engine2nd Stage Avionics

Inter-stage Skirt

2nd Stage Propellant Tank

2nd Stage Engine

2nd Stage LITVC Tank

Inter-stage Skirt

1st Stage Pressurant Tank

1st Stage Oxidizer Tank

1st Stage Fuel Tank

1st Stage Engine

Inter-tank Coupler

1st Stage Avionics

Spin Table

Image: Hiu, Donahue, Hinton, Doyle, White

AAE 450 Spring 2008 <7>

Backup Slide 3

AAE 450 Spring 2008 <7>

Structures

Image: Hiu