关键词: 微纳卫星, 空间外热流, 热控, 温度场, 在轨热分析

Abstract: The satellite thermal control system achieves the purpose of controlling the temperature level and temperature stability of the star by regulating the process of heat collection，transfer and emission on the satellite.It is very important to analyze the on-orbit thermal state of the satellite and to adjust and evaluate the thermal control measures based on the analysis results.Aiming at the key problems of thermal state analysis of low-orbit micro-nano satellites，the calculation method of the extra-space heat flow experienced by the satellites in orbit was given.On this basis，the temperature influencing factors and heat transfer characteristics were considered，and the instantaneous temperature calculation model of the satellite shell，radiator，internal environment，and internal and external stand-alone units were established.Taking an LEO（low earth orbit）micro-nano satellite as an example，the simulation calculation was carried out，and the results were analyzed and discussed，which provides a fast and simple analysis method for further indepth study of the thermal control design of the satellite.

Key words: micro-nano satellite, space heat flux, thermal control, temperature field, on-orbit thermal analysis