界面振荡对微细化沸腾传热影响机理研究

Effects of Vapor-liquid Interface Oscillation on Microbubble Emission Boiling Heat Transfer

本文通过数值模拟的方法对微细化沸腾时气膜振荡现象及其对气液界面周围液体流动和传热的影响进行了研究。计算结果表明,界面振荡可以强化气膜周围的对流传热过程,将界面附近对流传热系数提高10倍以上。结合实验研究进一步发现,界面振荡可以促进冷热流体搅浑,维持界面附近过冷度,对维持高热流密度下微细化沸腾的稳定发生起着重要作用。

The oscillation of vapor film occurred in microbubble emission boiling and its effect on the fluid flow and heat transfer of liquid in the vicinity of the vapor film were investigated with the help of numerical simulations in this study.Numerical results showed that the convection around the vapor film was significantly enhanced by the film oscillation and the heat transfer coefficient was increased nearly ten times.Based on the experimental results,it was further found that the vapor-liquid interface oscillation could accelerate the mixing of hot and cold liquid and sustain the local liquid subcooling near the vapor film,which played an important role in sustaining the stable occurrence of microbubble emission boiling at high heat flux.