小韦伯数下液滴撞击光滑壁面的数值模拟

Droplet spread on the free-slip surface under small Weber numbers was studied numerically by using the front tracking method (FTM). The results show that when the initial kinetic energy of the droplet is small (We = 12), the surface energy dominates the energy budget, so the maximum spreading rate β_max increases monotonically with the increase of Re. However, as the initial kinetic energy increases to a moderate level (We = 30), there will be a competition mechanism between the droplet viscosity and the strong strain induced by the droplet deformation among the domination factor during the energy conversion process, which will lead to a non-monotonic change in β_max as the Re increases. While with the further increase of the droplet initial kinetic energy (We = 60), the kinetic energy dominates the energy conversion process of the droplet spreading, and the maximum spreading rate β_max increases monotonously with the increase of Re again. In addition, when the droplet is spreading in the cases of without the "gas film", the disappearance of the surface tension at the bottom of the droplet causes the droplet to have a larger β_max.