Droplet splashing on a wet moving wall

The splash of a liquid drop onto a moving solid wall covered with a thin film of the same liquid is simulated numerically for an impact Reynolds number of 1000 and a Weber number of 400. A two-phase flow lattice Boltzmann model is employed for the simulations. The characteristics of drop splashing on the wall are investigated by systematically varying the impact angle and wall speed. The angle of incidence $\theta$ ranges from 0 to 60 degrees, while the wall speed to the initial drop velocity ratio Uw varies from 0 to 3. In case of Uw equals to 0 and $\theta $large than 0 degree, the splashing is asymmetric. The increase of the angle leads to the transition from splash to partial splash. The present results indicate the existence of a critical $\theta $c value of about 55 degrees, which is determined by the liquid film thickness, Reynolds and Weber numbers.