Previous lattice Boltzmann model (LBM) studies on solid entry/exit problems are limited to the free- surface LB model in which effects of the surface tension and gas phase are neglected, the surface wetta- bility cannot be adjusted, boundary conditions need to be applied on the interface, and the interface has to be tracked during time. In addition, conventional macroscopic models for simulating the phenomenon such as Volume of Fluid (VOF) and Constrained Interpolation Profile (CIP) have the same difficulties with the interface, besides the higher computational cost and time. Therefore, for the first time in this paper, a robust pseudo-potential based multi-phase LB model is coupled with moving boundary LB schemes for simulating liquid entry/exit of solids with the circular cylinder as a selected case study without los- ing generality. The current model has none of the free-surface LBM limitations and is also superior over the conventional models by automatic interface capturing and lower computational cost and time. Fur- thermore, the integrated model is capable of simulating the phenomenon at relatively high We and Re numbers and density ratios as high as the water/air one. Formation and propagation of the pressure wave in the case of liquid entry are shown and discussed. Cavity and subsequent pinch-offand jets formations for a hydrophobic surface are also captured and quantified. Effects of the We, Re, Fr , and impact velocity on the pinch-offtime and depth, and velocity of subsequent jets are investigated, plotted, and discussed in details. Results show that the pinch-offtime and depth are independent of the surface tension and liquid viscosity, but are increased linearly with the impact velocity. Furthermore, the velocity magnitude of both downward and upward jets after the pinch-offis increased with Re and We numbers and is de- creased with Fr number.

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