Abstract

Growth of a nonisothermal bubble on a heated horizontal surface in a subcooled flow is studied to determine the significance of different heat transfer mechanisms on the bubble growth. The heat transfer mechanisms that are considered are (1) microlayer evaporation, (2) transient thermal boundary layer conduction, and (3) bubble surface evaporation and condensation. The results indicate that a different heat transfer mechanism dominates the bubble growth at different stages of the bubble growth. And, the temperature gradient inside the bubble decreases after bubble liftoff in high Reynolds numbers. The results also show an oscillatory heat flux during the initial stages of the bubble growth.

摘要

研究了非等温气泡在过冷流中在加热的水平面上的生长，以确定不同传热机制对气泡生长的重要性。所考虑的传热机理是（1）微层蒸发，（2）瞬态热边界层传导和（3）气泡表面蒸发和冷凝。结果表明，不同的传热机制在气泡生长的不同阶段主导了气泡的生长。并且，气泡上升后，气泡内部的温度梯度以高雷诺数减小。结果还显示出气泡生长初期的振荡热通量。