Computer aided thermal analysis of a technology demonstration satellite (NPSAT1)

Abstract

The thermal control system of a spacecraft is used to maintain all subsystems within their temperature limits. It must be able to deal with different operational states and orbital environments. Theory provides knowledge about the quality of effects of certain designs options, but for a complex system like a spacecraft, simulations are needed for quantification. This thesis has two main purposes. Critical parts concerning thermal control in the current design are identified and the thermal design for NPSAT1 is improved. Furthermore this developed design is analyzed for being appropriate and temperature-time predictions are developed. Both design objectives are accomplished with the help of EDS I-DEAS with Maya's TMG. After defining all constraints and requirements, a thermal FE model is developed, documented, and verified. Simulations with this model are used to track insufficiencies concerning the thermal design. With their help, different design approaches are analyzed to obtain sensitivity information. Proposals for design changes are made. Four worst-case scenarios are defined and the developed design is evaluated with their help. Temperature-time histories are obtained with an emphasis on the temperature sensitive electronic boxes. A special analysis is provided for the connection of the solar cells to the structure.