低气压温控设备的舱内环境温度影响因素分析

低气压温控设备用于模拟临近空间低气压和高低温环境,低气压环境的温度场控制是低气压温控设备的关键指标,也是设计难点。文章首先通过Fluent软件对无风扇扰动的低气压舱中的环境温度进行数值仿真,研究热沉开孔对舱内环境温度的影响;在低气压舱模型中增加风扇模型,分析强制换热对低气压舱内环境温度的影响。通过在低气压温控设备中进行的无强制对流的温度控制试验,研究此时空间温度的降温速率、试验舱压力和舱内试件工装对舱内环境温度的影响。数值计算和试验研究结果表明,热沉开孔、扰动风扇、试验舱压力和试件工装均对低气压舱内环境温度有影响,在低气压温控设备的研制中,需综合考虑上述因素。

The influence factors of environmental temperature in the chamber of low pressure and temperature control facility

The low pressure and temperature control facility can be used to simulate the environment of the near space, characterized by low pressure and high & low alterating temperature. First, the control of the temperature field concerns a main technical specification of the low pressure and temperature control system, which is relatively difficult. The environmental temperature in the low pressure chamber without fan is numerically simulated by the software Fluent, and the effect of the opening hole in the heat sink on the environment temperature inside the chamber is studied, then the fan model is added to the low pressure chamber, and the effect of the forced-convection heat transfer on the low pressure chamber is analyzed. The temperature control test in the low pressure chamber without the forced-convection heat transfer is completed, to evaluate the influening factors such as the cooling rate, the chamber pressure, and the test pieces and the toolings. Simulation and test result all indicate that the hole in the heat sink, the disturbance of fan, the pressure of the chamber, and the test fixtures all have some effect to the environmental temperature of the low pressure chamber. Those factors should be considered integratedly in the development of low pressure and temperature control facility.