Thermal Control Subsystem Impact Heat Thermal Model

1. Thermal Control Subsystem Impact Heat Thermal Model Stephane Charbonneau

2. Presentation Outline • Heat Created from Impact Phase • Thermal Model • Instrument Temperatures • Phase Change Material • Future Work Stephane Charbonneau

3. Heat Created from Impact Phase • Kinetic energy equation(25% to 50% is impact heat): • Deep-Space 2 experimental data: • nose cone temp: 800 K and 1000 K • body temp: 333 K and 380 K Stephane Charbonneau

4. Thermal Model • Using I-DEAS TMG software • Can set different material properties, temperatures, geometries • Assuming: • solid aluminum • experimental impact heat data • conic nose shape Stephane Charbonneau

5. Thermal Model • Meshing key to setting boundary conditions • Must find balance between computation time and size of mesh Stephane Charbonneau

6. Thermal Model • Steady state results using TMG analysis • Heat stops about 2 cm into the regolith Stephane Charbonneau

7. Instrument Temperatures • Battery survival temperature is limiting factor (-30°C) • Communications operating temperature is limiting factor( -20°C to 50°C) Stephane Charbonneau

8. Instrument Temperatures • Instruments may be placed according to temperature limitations • Antenna already near top • Payload must be near bottom • Still need more component data Stephane Charbonneau

9. Phase Change Material • Absorbs heat as phase changes • Solid to liquid phase change is preferable • Adds extra volume • Still have to get rid of heat Stephane Charbonneau

10. Phase Change Material • Stores energy (will need to be released) • Mass equation for phase change material(heat of fusion 238 J/kg): • Where mass [kg] and heat [Wh] Stephane Charbonneau

11. Stephane Charbonneau

12. Future Work • Continue to iterate TMG model as design is refined • Transient results • Model subsystem components • Find heat generated by internal electronics Stephane Charbonneau

13. Gantt Chart Stephane Charbonneau

14. Questions?