为研究固体表面结构对液滴撞击液膜后演变行为的影响规律，采用CLSVOF方法模拟液滴撞击不同尺寸槽道上的表面液膜的流动过程，获得不同槽道高度和宽度时液滴撞击液膜后的演变行为，探索撞击速度、液膜黏度和表面张力对撞击后液膜铺展行为、水花飞溅高度和二次液滴形成的影响。结果表明，槽道结构对液滴撞击液膜后的动态行为具有显著影响，随着槽道高度的增加，冠状水花厚度越薄，越容易产生二次液滴；随着液膜黏度的增大，则抑制冠状水花形成与二次液滴的产生；液膜表面张力减小时，射流更加明显，二次液滴数更多，飞溅现象提前，冠状水花消失时间延后。
In this paper we present results of a numerical investigation into a single drop impact on a rectangular grooved substrate with thin liquid film covering it. Particularly, effects of the height and width of the ridge on surface and dynamic behavior of droplet impact into thin liquid film were mainly studied. Simulations were performed using CLSVOF (coupled level-set and VOF) to track the air-water interface accurately and to keep conservation of mass at the same time. Results show that the structure of grooved surface has significant influence on the evolution of liquid film when droplet impacts on it. With the increase of rectangular groove height, the thickness of the coronal water becomes thin and the secondary droplets produce easily. Increase of the viscosity of liquid film inhibits coronal water flower formation and secondary droplet generation. When the surface tension of liquid film reduces, the jet is obvious and more secondary droplets produce. The splash phenomenon is advanced, and the disappearance of the crown water flower is delayed. Our research sheds some lights on the fundamental understanding of many industrial phenomena.
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