AAE450 Spring 2009 Tim Rebold 01/22/09 Structures and Thermal Thermal Control Systems [Tim Rebold] [STRC]

AAE450 Spring 2009 Thermal Management Systems [Tim Rebold] [STRC] Thermal Control Systems ActivePassive Sensors Heaters Electric MLICoatings Control Roll ThermostatThermistor Applications: 1) Payload 2) Computers & Spacecraft Hardware 3) Thruster Fuel Systems 4) Solar Arrays 5) Batteries Thermal Louvers RTG

AAE450 Spring 2009 Active Thermal Control  Resistive Electric Heaters –Ulysses (367 kg) thermal management set-up  RTG’s –Apollo, Pioneer, Voyager, Viking, Galileo, Cassini, Ulysses – W heat output, kg RTG mass [Tim Rebold] [STRC] Heaters Hot Case Heater Cold Case Heater X Wing Heaters Longeron Heater Mean Power Consumption (W) Heat Dissipated (W)

AAE450 Spring 2009 Backup Slides  References – ops.jpl.esa.int/ulsfct/spacecraft/scframe.htmlhttp://ulysses- ops.jpl.esa.int/ulsfct/spacecraft/scframe.html – ceSystems/cs_ss_subsys_tms_tl.asphttp:// ceSystems/cs_ss_subsys_tms_tl.asp – moelectric_generator#cite_note-GLB-11http://en.wikipedia.org/wiki/Radioisotope_ther moelectric_generator#cite_note-GLB-11 [Tim Rebold] [STRC]

AAE450 Spring 2009  Future Work –Need operating temperature ranges on various spacecraft components –Output heat generated from electronics and heat dissipating devices –Spacecraft dimensions –Determine mass and size of thermal systems –Estimate cost [Tim Rebold] [STRC]

AAE450 Spring 2009 Thermal Louvers  Vary radiation transfer of underlying surface (spaceflight hardware)  Operates in -40 degrees C to +100 degrees C environment  Weight is approximately 0.89 lbm/ft^2 of louver area [Tim Rebold] [STRC]

AAE450 Spring 2009 Thermal Louvers  Factory selectable from 0 to 40 degrees C with a +/-2 degrees accuracy  Factory selectable at either 10 or 18 degrees above the open temperature  The louver assembly is fully qualified for spaceflight and has flown on the NASA/GSFC XTE and JPL STARDUST.  Contact [Tim Rebold] [STRC]

AAE450 Spring 2009 Thermistors  NASA Goddard SMD NTC Thermistor –made by QTI –meeting or exceeding all the requirements of NASA/GSFC S-311-P-827 –operating temperature range: -55°C to +125°C [Tim Rebold] [STRC] Images from (QTI website)

AAE450 Spring 2009 Ulysses Configuration [Tim Rebold] [STRC] Images from (JPL website)

AAE450 Spring 2009 RTG models for space [Tim Rebold] [STRC] Table based from