气泡从基板上脱离的运动规律，对于研究核态沸腾的机理及相变传热有着重要意义。利用Level Set方法建立二维轴对称非稳态模型对该问题进行数值模拟，获得气泡在浮力、黏性力、惯性力与表面张力共同作用下的运动规律，分析不同Re数、Bo数和表面润湿性对气泡脱离基板规律的影响，并获得气泡从基板脱离时的临界参数。结果发现，当Re数增大，气泡上升的惯性力就增大，气泡越容易脱离；当Bo数增加，气泡会从完全脱离转变为部分脱离；随着表面润湿性的降低，气泡与基板的接触面积增大，气泡与基板及附近液体的作用力就增大，越难以脱离。
The detachment of bubbles from the substrate is of great significance for nucleate boiling and phase-change heat transfer. In this study, the two-dimensional axisymmetric model is built up using the Level Set method, and the bubble dynamics is obtained by considering buoyant force, viscous force, inertial force, and surface tension in terms of non-dimensional parameters. The effects of Reynolds numbers, Bond numbers, and surface wettability on the bubble detachment from the substrate are revealed, and the critical parameters for bubble detachment are also obtained. We find that, with the increase in Reynolds number, the inertial force increases, leading to easy detachment of bubbles from the substrate. With the increase in Bond numbers, the bubble transits from the complete detachment to the partial detachment. With the decreases in surface wettability, the contact area between the bubble and substrate increases, leading to large interactive forces of the bubble with the substrate and the liquid near the contact area. Thus the bubble is difficult to detach from the substrate. These studies may be quite useful for the study of nucleate boiling heat transfer.
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