深冷环路热管稳态运行特性的理论分析

基于能量平衡、压力平衡以及质量守恒,建立了氮工质深冷环路热管(CLHP)的稳态数学模型,模拟结果同实验数据具有良好的一致性.应用该模型对CLHP的稳态运行特性进行了理论分析,考察了寄生热载荷、次蒸发器功率等对CLHP运行性能的影响,并得出如下结论:同常温环路热管相比,CLHP的传热能力明显减小;当主蒸发器热载荷较小时,寄生热载荷以及反重力高度的存在使CLHP的稳态运行温度明显升高,而通过对次蒸发器施加功率可显著改善CLHP的工作性能;CLHP最高运行温度/压力随储气室容积的增大而减小,相应的,其最大传热能力将受到限制.

Theoretical analysis of steady-state operating characteristics of a cryogenic loop heat pipe

Cryogenic loop heat pipe is one of the key devices in the high-efficiency cryogenic heat transport technology. Based on energy balance, pressure balance and mass conservation, the steady-state mathematical model of a cryogenic loop heat pipe with nitrogen as the working fluid was established in this paper, and the modeling results showed good agreement with the experimental data. A parametric study including the parasitic heat load, adverse elevation, the power on the secondary evaporator and volume of the gas reservoir was conducted based on the model, and the conclusions below can be drawn: the heat transport capability of cryogenic loop heat pipe is obviously reduced compared with ambient loop heat pipe; when the heat load applied to the primary evaporator is small, the steady-state operating temperature is high due to the existence of the parasitic heat load and adverse elevation. However, the performance of cryogenic loop heat pipes at small heat loads can be notably improved by the application of heat load to the secondary evaporator. The maximum operating temperature/pressure decreases as the volume of the gas reservoir reduces, and the maximum heat transport capability will be limited accordingly.