SENSETIVITY ANALYSIS OF SPIN RATE OF A SMALL SATELLITE ON ITS THERMAL CONTROL

In this paper transient heat transfer and temperature distributions calculations for a small satellite model in LEO (low earth orbit) with altitude of 700 kilometers for spin rates of 1,3,5,7 rpo and fast has presented. The effects of satellite spin rates on absorbed orbital heating rates (earth infrared radiation, Albedo and solar radiation) by external surfaces of satellite are investigated. The temperature distribution of elements and surfaces are calculated too. This calculation has been performed to choose an appropriate spin rate for a specific satellite in order to satisfy thermal control requirements. The model includes a small communication satellite and most sensitive elements as far as thermal control is concerned have been considered in this calculation. According to the obtained results, in this orbit, spin rate alteration has no significant effect on the amount of orbital heating rates received by top and bottom plates of the satellite. The amounts of environmental loads received by each of lateral panels vary rapidly with changing the satellite spin rates. Lateral plates experience different temperature conditions through changing the spin rate depending on beta angle. The temperature of all internal components depend on these variations changes too. It is concluded that a spin rate of 5rpo provides the best conditions from thermal control point of view for surfaces and elements of the satellite.

کلیدواژه ها:

Satellite ، Spin rate ، Thermal control ، orbital heating rate