Abstract:

A transient coupling lumped heat transfer model is proposed for the internal avionics and external spacecraft structure, which is consistent with the heat transfer characteristics of a general spacecraft thermal control system. The determination method for thermal stabilization criterion is developed, which is based on the thermal time constant. The spacecraft thermal time constant is achieved analytically for dual-node coupling heat transfer process. The relation between the thermal stabilization temperature difference and the temporal change rate of the temperature is derived. The real-time correction method for the thermal time constant is proposed, which is based on the temperature curve fitting technology by using the Levenberg-Marquardt algorithm and least squares method. Furthermore, the real-time correction method is able to meet the demand of the thermal stabilization criterion determination for the multi-node coupling heat transfer spacecraft system. The validity of the actual thermal stabilization criterions is discussed. The determination method of the thermal stabilization proposed in this paper can be applied to the spacecraft thermal balance tests.

Key words: Thermal balance test, Thermal stabilization criterion, Thermal time constant, Thermal control