1 aerothermal ground testing of flexible thermal protection systems for hypersonic inflatable...
TRANSCRIPT
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Aerothermal Ground Testing of Flexible Thermal Protection Systems for
Hypersonic Inflatable Aerodynamic Decelerators
Walter E. Bruce III, Nathaniel J. Mesick, Paul G. Ferlemann,Paul M. Siemers, Joseph A. Del Corso, Stephen J. Hughes,
Steven A. Tobin, and Matthew P. Kardell
NASA Langley Research Center
9th International Planetary Probe Workshop
16-22 June 2012, Toulouse
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Outline
• Flexible Thermal Protection System (FTPS) Overview
• Previous Work
• Test Conditions
• Testing Methodology
• Boeing LCAT Facility
• CFD Analysis
• Hardware Design
• Conclusions
• Future Plans
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Flexible Thermal Protection SystemOverview
• Flexible TPS (FTPS) Benefits– Larger Heatshield
– Reduced Ballistic Coefficient
– Greater Payload Mass Delivered
– Higher Landing Altitude
• FTPS Requirements– Flexible (Foldable)
– Handle Rigors of Packing and Stowage
– Handle Aerothermal Loads
– Light Weight
– Compact to Small Volume
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Flexible Thermal Protection SystemsComponents
A FTPS is Constructed from Three Basic Components
Insulator – Heat Load
Outer Cloth – Mechanical Loads
Gas Barrier - Permeability
FTPS Materials and Function1. Outer Cloth – Handles Mechanical Loads
• Aerodynamic Shear
• Protects Insulator from Abrasion and Handling Issues
2. Insulator – Manages Heat Load
• Insulator Sized to Maintain Supporting Structure at Desired Temperature
3. Gas Barrier – Prevents Hot Gas Penetration to Support Structure
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Previous Aerothermal Testing
• Tested in Three Different Facilities– 8-Foot High Temperature Tunnel
• High Shear Force
• Limited Heat Flux
– Laser Hardened Materials Evaluation Laboratory• No Flow
• Optical Property Uncertainty
– Panel Test Facility• Low Pressure
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Test Conditions
0
5
10
15
20
25
30
0 1 2 3 4 5 6 7 8 9 10 11
Hea
t Flu
x (W
/cm
2)
Surface Pressure (kPa) [estimated as 2 times dynamic pressure]
HEART MaxHeating Point
HEART "Max-Max"Test Point
IRVE-3 "Max-Max"Test Point
IRVE-3 MaxHeating Point
HEART MaxPressure Point
IRVE-3 MaxPressure Point
Heat SurfaceFlux Pressure
(W/cm2) (kPa)20 3.130 4.840 6.650 4.0
Test Conditions
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Testing Methodology
• Focusing on IRVE-3 and HEART Trajectories– Validation and Verification for model Development
– FTPS Development for HEART Vehicle
• Max-Max for Quick Screening– Over-Test of Combined Heating and Pressure
– Can Lead to False Negatives
– Multiple Material Systems
• Stagnation and Shear Testing– Matching Heat Flux and Pressure
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Boeing LCAT Facility
Oblique View Camera
Pyrometer
Nozzle
Huels Arc Heater
Side View Cameras
Top View Cameras
Oblique View Port
Calibration Probe
Test Model
Nozzle Exit
Viewing Window
InstrumentationHousing
Test Sample
Semi-Elliptic Nozzle Exit
Water-Cooled Model Holder
Rotary Model Injection System
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Testing
Shear Test
Flow
Stagnation Test
Flow
Stagnation Model In Test
Instrumentation
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Comparison: Analysis to Shear Testing
Nozzle Exit
Nozzle Throat
Test Sample
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Model Holder DesignStagnation
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Model Holder DesignShear
Test Sample
Semi-Elliptic Nozzle Exit
Water-Cooled Model Holder
Rotary Model Injection System
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Sample Test Results
Time (sec)
Tem
pera
ture
(°C
)
0 50 100 150 200 250 300 350 4000
200
400
600
800
1000
1200
1400TC-2KTC-3KTC-4KTC-5KTC-6KTC-7K
Exposure Duration
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Conclusions
• Test Methodology and Associated Hardware Developed
• Successful Testing in Boeing LCAT Facility
• Acquiring Validation/Verification Data for Code Development
• Supporting Development of FTPS Development for HEART Vehicle
• Analysis of Geometry Shape Change in Shear Testing
• Continue Test Technique Development
• Continue Testing In LCAT Facility