月地高速再入返回器热控设计及实现

Design and implementation of circumlunar return and reentry spacecraft thermal control system

针对月地高速再入返回器不同阶段大功率散热、小功率保温与高速返回过程中高温隔热之间的突出矛盾,以及狭小、局促空间内设备热量的收集、传输、排散与阻断等技术难题,首次构建一种基于柔性自适应"热开关"的小型再入返回类航天器热控体系,成功研制出一套基于异构式环路热管的一体化柔性、高效热管理系统.在轨飞行数据表明:核心热控产品环路热管控温运行模式下实际传热能力超过65 W,阻断模式下漏热量小于2 W,"热导比"大于30,能够很好地实现"热开关"功能,确保了返回器所有设备的温度水平优于指标要求.

There are three aspects of difficulties in the thermal control system design of circumlunar free return and reentry spacecraft. In the on orbit-working mode, large thermal load is required to be rejected; in the storage mode, the heat load is small and additional heating is needed, while heat insulation is required in the reentry. Moreover, the technique of equipments＇ heat collection, transmission, rejection and insulation in the narrow space is very difficult. To arrange the complex thermal requirements, a new thermal control hierarchy system for small reentry spacecrafts based on the flexible and self-adaptable heat switch is constructed for the first time, and an integrative flexible and efficient thermal control system based on heterogeneous loop heat pipe （LHP） is successfully developed. The on-orbit flight data show that the actual heat-transfer capability of the pivotal thermal product LHP is more than 65 W in the temperature-controlled working mode, while the heat leak is less than 2 W in the blocking mode, and the ratio of thermal conductivity is more than 30, which means a good realization of the heat switch function, and ensures that the temperature levels of all the circumlunar free return and reentry flight test vehicle equipments are better than index requirements.