Thermal

The Thermal Control System (TCS) of the satellite makes sure that the temperatures of all the components are within the corresponding admissible limits during all the operational stages of the satellite. This does not only refer to normal operation, but also to the initiation and also possible safe mode stages.

To date, analytical examinations of this satellite subsystem have been carried out. The results stated that the satellite would neither be able to survive in permanent darkness nor in permanent sunlight. As the real situation however is a constant change of light and darkness (duration of the orbit is approx. 93 minutes), it is in principle possible that the satellite survives, with the condition of sufficient insulation.

With the support of the Company Active Space Technologies more profound numerical computer analyses were carried out. The result with a first thermal layout was slightly raised temperatures for all the subsystems, according to the simulation merely the reaction wheels showed a considerably increased temperature because of their suboptimal attachment to the satellite bus.

The response to the simulation results was the addition of a third radiator surface in the design; the layout and the attachment of the reaction wheels was changed.

Fig. 1: Preliminary thermal model of BayernSat

Fig. 2: Electronic temperatures (blue = reaction wheels)

Fig. 3: Bus temperatures

In the coming months we will carry out more profound analyses with the support of CASE and Kayser-Threde from Munich. The well-known analysis software Thermica will be used for these analyses.