4/08/2003 1

School of Aeronautics and Astronautics

TPS Methods Report

4/08/2003 2

School of Aeronautics and Astronautics

Goals

1) Meet Boundary Condition

477.95O K

2) Minimize TPS Mass

4/08/2003 3

School of Aeronautics and Astronautics

Heat Conduction Problem

1( ) ( ) ( )p

T TC T k T A Q T

t A x x

TPS Material #1

TPS Material #2

TPS Material #j

ConvectionhA(Tinf – TWall) (Type 3)

ChA(ir-iwall) (Type 1)

Time DependantHeat Flux

awAqrad

ReradiationewA(T4

wall – T4rad)

X

4/08/2003 4

School of Aeronautics and Astronautics

SODDIT

Block Data Type

1 Control Flags

2 Title or heading characters

3 Print intervals, print times for results

4 General problem constraints

5 Material property data

6 Initial temp. distribution, node and element data

7 Boundary condition for front face

8 Boundary condition for back face

9 Enthalpy of boundary layer gas

10 Energy generation rate constants

4/08/2003 5

School of Aeronautics and Astronautics

MATLAB & SODDIT

number_of_materials = 3;materials(1) = struct('name','SLA-561V.m', 'thickness',.04,'nodes',15,'ablator',1,'mult',1);materials(2) = struct('name','AETB.m', 'thickness',.01,'nodes',15,'ablator',0,'mult',1);materials(3) = struct('name','Graphite.m', 'thickness',.01,'nodes',15,'ablator',0,'mult',0);

0 0 * *t t t mult scale

4/08/2003 6

School of Aeronautics and Astronautics

SODDIT & MATLAB

Soddit_control.m Soddit_between.m

Mysoddit.m

Get_plt_data.m

SODDIT

Material DataSweep of scale

.qw file

.inp File_plt.txt

Temp HistoryThickness HistoryMaximum Time

Material DataSingle value of scale

.qw file

4/08/2003 7

School of Aeronautics and Astronautics

Code Validation

Physical Characteristic Teflon SLA-561V

Ablation Temp (0K) 822 588

Heat of Formation (J/kg)

2.19e6 5.41e7

Conductivity (W/(m0K)) ≈3 ≈ .2

Teflon

AETB

SLA-561V

Graphite-Epoxy

5cm

2cm

1cm

TPS 1 TPS 2

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School of Aeronautics and Astronautics

Heat Flux

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School of Aeronautics and Astronautics

Temp History

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School of Aeronautics and Astronautics

Ablation Comparison

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School of Aeronautics and Astronautics

Test Case

AETB

SLA-561V

Graphite-Epoxy

5cm

2cm

1cm

Completed 600s Mission DurationInner Wall Temp meets 477.95O K Boundary Condition

0 0 * *t t t mult scale

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School of Aeronautics and Astronautics

TPS Minimization

Scale = -.42

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School of Aeronautics and Astronautics

Weight Savings

AETB

SLA-561V

Graphite-Epoxy

2.32 cm

.58 cm

1 cm

Original Density 37.83 kg/m2 Minimized Density 29.2 kg/m2

23% Savings over Reference!!!

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School of Aeronautics and Astronautics

.m file Name Short Description

Mysoddit.m Make .inp file, call SODDIT, get results

Soddit_control.m Start here, define TPS and scale values

Soddit_between.m Sweep the scale values, return T_max, Time_Max

Write_block_1.m Writes block 1 data to .inp file

Write_block_2.m Writes block 3 data to .inp file

Write_block_3.m Writes block 3 data to .inp file

Write_block_4.m Writes block 4 data to .inp file

Write_block_5.m Writes block 5 data to .inp file

Write_block_6.m Writes block 6 data to .inp file

Write_block_7.m Writes block 7 data to .inp file

Write_block_8.m Writes block 8 data to .inp file

Fcopy.m Copies one file and appends to another

Findline.m Finds given line in a file and moves file pointer to that location

Create_script.m Creates BSH script to run SODDIT

Get_plt_data.m Get data from _plt file

SLA-561V.m SODDIT data for SLA-561V Ablator

Teflon-Ablate.m SODDIT data for Teflon Ablator

AETB.m SODDIT data for AETB insulator

Graphite.m SODDIT data for graphite-expoy