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研究微细化沸腾(MEB)发生时界面的变化过程,可以帮助理解其具有高强度传热能力的原因.基于流体体积模型(VOF)方法,通过修改其中控制方程的源项,综合考虑界面的蒸发冷凝作用和气泡的扰动作用,对加热面上单个气泡的界面变化过程进行了数值模拟,着重分析了过冷度在MEB形成中的作用.数值计算结果表明,气泡在较低过冷度下(15 K)冷凝速度较慢,气泡界面变化比较平缓,随着过冷度的增加,气泡界面出现比较剧烈的波动过程,说明过冷度升高会对气泡的界面形态有显著的影响;界面上强烈的凝结作用和所引起的扰动过程,对于MEB的形成和强化传热过程,均起到了重要作用.“,”The study of the interface evolution during microbubble emission boiling is of great importance in understanding the enhanced heat transfer ability of MEB.A numerical work was carried out to simulate the evolution of the interface of a single bubble on a heating surface based on Volume Of Fluid (VOF) model,in which the source terms are modified to combine both the evaporation and condensation process across the interfaces and intensive disturbance caused by microbubble motion.This paper focused on the effect of liquid subcooling on the formation of MEB.The numerical results showed that at low liquid subcooling (15 K) a mild variation occurred to the vapor-liquid interface due to the slow condensation rate at the interface.With the increasing of liquid subcooling,a dramatic surface disturbance emerged,proving the significant effect of a higher subcooling on interface changing.All of these indicated that both the strong condensation and the intensive disturbance it caused played a key role in triggering MEB and in enhancing the heat transfer of MEB.