含高分压不凝气体的蒸汽在分离式热管内凝结换热

Flow and condensation of vapor with high partial pressure non-condensable gas in a separate heat pipe

摘要: 设计建立了一套以水为工质的分离式热管系统实验台,系统冷凝端采用水冷套管式换热器.在此实验台基础上研究了不抽真空、有大量不凝性气体存在于分离式热管的凝结放热问题,测定了在不同的入口蒸汽温度、循环蒸汽流量、冷却水进口温度及流量条件下混合气体在圆管内凝结换热的情况,分析了这些参数对换热过程的影响.同时,还对套管内含高分压不凝性气体——空气——的水蒸汽凝结换热物理模型进行了研究,并建立了相应的数学模型.模型中除了质量守恒、动量守恒、能量守恒和界面控制方程外,还增加了流动扩散和凝结控制方程.模型结果显示蒸汽放热量与实验测定值基本吻合,偏差在8%~15%之间.

Abstract: A set of separate heat pipe (SHP) with water as medium was built. The flow and condensation of vapor with non-condensable and high partial pressure air in the SHP were measured in the experiment. The physical model of the flow and condensation of vapor-air mixture was studied and the related numeral model was founded. Except for the mass, momentum and energy conservation equations, the diffusion and condensation equations were added to calculate the distribution of the mixture in the mathematical model. The numerical result agrees well with the experimental data, and the deviation is between 8% and 15%.