过冷沸腾气泡在圆形朝下壁面上特性实验研究

摘要

The equivalent diameter of a vapor bubble starting to move and its motion behavior are important for the research on mechanism of boiling heat transfer.The vapor bubble's growth and motion on a downward facing circular surface in subcooled boiling liquid under various heat fluxes are studied experimentally by using a high-speed camera.The experimental results show that in the process of its growth and movement,the vapor bubble changes from a sphere in the growth process at the initial stage to an elongated ellipsoid in its sliding process,and then it is broken.The heat flux has an influence on the equivalent diameter of vapor bubble starting to move,and the equivalent diameter of vapor bubble starting to move increases with the increasing of heat flux.%气泡的始动直径与运动过程对于揭示沸腾传热机理有着重要意义。利用高速摄像机对不同热流密度条件下，过冷沸腾液体中气泡在圆形朝下壁面上生长及运动的过程进行了实验研究。研究表明：在气泡的生长及运动过程中，气泡的形状从生长过程初期阶段的近似球体变化到滑移过程被拉长的椭圆体，直至最后消失；壁面热流密度对气泡的始动直径有一定影响，热流密度越大气泡的始动直径也就越大。