A numerical study on splash of oblique drop impact on wet walls

Oblique impact of a liquid drop onto a wet solid wall with a moderate Weber number is simulated numerically by using a two-phase flow lattice Boltzmann model. The simulation is conducted for a wide range of impact angle θ from 0° to 60°. The characteristics of drop splashing on the wall are determined together with the flow patterns accompanying drop impact. The effects of the impact angle on the crown formation and its evolution are quantified. Results show that in the case of θ>0°, splashing is asymmetric. The increase of the angle leads to the transition from splash to partial splash, which indicates the existence of a critical θc for the studied conditions. Above this critical θc, the drop splashing is completely suppressed on the downstream side. In addition, a comparison of flow patterns of oblique drop impact on a stationary wall and normal drop impact on a moving wall is made to show their similarities and differences.