Abstract: Impinging of a liquid drop onto a thin film of the same liquid is a classic problem of gas-liquid two phase flows which widely exists in the nature as well as in many industrial applications. In this paper, the impinging process is simulated numerically with the lattice Boltzmann method (LBM). This is a novel method in computational fluid dynamics and has many advantages due to its meso-scale foundation compared to macro-scale equation based traditional methods.A so-called “single-phase” lattice Boltzmann model for interface fluid flow is used to obtain the three important characteristics of impinging with three different combinations of Reynolds number (Re) and Weber number (We). Numerical results show that different phenomena of deposit, splash, and splash with separated fluid drops erupted during impinging will take place as Re and We increase. Numerical results are in good agreement with experimental and analytical results, showing usefulness of LBM in studying gas-liquid two phase flows.

Key words: lattice Boltzmann method (LBM), numerical simulation, single-phase model, splash, gas-liquid two phase flow