载人航天器舱内流动换热仿真分析

Flow and Thermal Transfer Simulation Analysis on Manned Spacecraft Cabin

针对载人航天器轨道舱内的流动换热问题,在合理构建研究对象的基础上,采用仿真分析手段研究了舱内复杂的流动换热过程。在给定相应的边界条件下,对轨道舱内电子设备、风扇、冷凝加热器及航天员活动空间速度场和温度场进行了数值仿真,分析了设计参数对舱内对流换热和航天员活动舒适性的影响。研究发现,舱内气流的流向一致性更有利于舱内对流换热;与层流相比采用湍流方程模拟舱内流动更为合理;轨道舱漏热量随舱内电子设备的发热量在超过80W/m2后线性递增,随着舱内外温差的影响呈现出幂函数特性。通过合理调节和优化舱内外设计参数,启动主动热控系统的调节机制,可以获得适宜航天员生存的舱内环境。

It is a complicated problem to simulate orbital module thermal transfer and flow distribution of manned spacecraft. Simulation analysis was employed to simulate the complex forced airflow in pressured cabin by building reasonable and effective physical model. Under the same given boundary conditions, the numerical simulation of airflow and temperature fields were calculated for the whole space structure and onboard devices, including electronic equipments, fans, condensers and heaters and astronauts. The design parameters were optimized and these influences on convective thermal transfer module and astronaut’s comfort level were analyzed. It was found that uniform flow was very important to convective thermal transfer in the cabin and turbulent equations were reasonable to be utilized. Besides, orbital module heat leakage is linear related to the electronic equipments ’calorific capacity when over 80W/m2. It increases along with the changes to temperature difference between inside and outside cabin in the feature of a power function. The results show that these key design parameters optimizations are effective to obtain desired action environment for astronauts with the opening regulation mechanism of active thermal control system.