池沸腾现象中热毛细对流的成因

Origin of Thermocapillary Convection in Pool Boiling

针对微重力条件下单组份液体池沸腾现象,探讨了有关热毛细效应作用及其成因的不同观点,指出正确描述气液相变界面两侧的温度关系是解决争议的关键.详细评述了现有的气液相变界面温度模型,发现气液相变的非平衡特征会导致气液界面上产生温度梯度,引起表面张力的显著差异,从而驱动热毛细对流的形成.但现有气液相变界面温度模型机理差异迥然,预测结果也差别很大,因此,需要更深入研究.

The phenomenon of boiling heat transfer is broadly exists in many nature and technology fields, covering from human daily life to the manned space flight. The study of the phenomenon of boiling heat transfer is one of the most important research fields in science and engineering. In the present paper, different view-points on the origin of thermoeapillary convection are discussed for the case of one component liquid pool boiling phenomenon in microgravity. It＇s pointed out that the key problem is how to model the temperature jump condition across the vapor-liquid interface with phase change. Therefore, some existed correlations on the temperature jump condition across the vapor-liquid interface with phase change are reviewed in detail. It＇s found that the non-equilibrium of phase change will result in an obvious temperature gradient at the interface and then thermocapillary convection around the vapor bubble is driven by the surface tension gradient due to the temperature gradient. However, both the mechanisms and the predictions of these models are very different from each other, and no one can be generally recognized up to now, further study is needed.