Abstract: The trajectory model of dispersed drops and the model of basic flow for drop motion between two inclined parallel plates are derived and the calculation is optimized.The analytical results of numerical simulation indicate that with the variation of thickness of trickling film and plate distance, the density, viscosity and interfacial tension have different influences on the drop motion.The viscosity always has a great effect on the drop coalescence, while the effects of density and interfacial tension depend on the flow field.The variation of density, viscosity and interfacial tension may make the drop motion rotate tendentiously in the clockwise or anticlockwise direction with the axis parallel to a nearby plane wall. Hence, the density and viscosity may improve the coalescence condition in a certain extent.The simulation results match the experimental data well.The introduction of the basic flow is helpful for the model to reproduce the drop motion characteristics better in the stratified two-phase flow.

Key words: trajectory, coalescence, drop, interfacial tension, Archimedes number

摘要： 推导了分散相液滴运动轨迹模型和分层二相流基本流模型，并优化了计算方法。直接数值模拟结果表明：当层膜厚度和板宽变化时，流场的密度、黏度以及界面张力对界面处的液滴的作用方式不相同；黏度始终对液滴聚结产生明显的影响，而密度和界面张力对聚结的影响却因流场结构的变化而有所不同；密度、黏度及界面张力的变化使得液滴的顺时针或逆时针旋转运动更加具有倾向性。因此，密度和黏度在一定程度上可用于改善流场的聚结条件。数值模拟的结果与已知的实验结果吻合较好，而且，基本流的介入使得该模型能较好地反映液滴在分层二相流流场中的运动特性。

关键词: 轨迹, 聚结, 液滴, 界面张力, Archimedes数