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In recent years, many incidents have been reported involving engine power loss due to ice crystal icing. Ice particles in clouds cause this ice crystal icing; however, it is not easy to confirm the actual phenomenon because it occurs inside the engine during flight. Hence, the mechanism of its occurrence has not been fully elucidated. Understanding the mechanism is very important for improving the accuracy of ice crystal icing prediction. Numerical simulations are required to predict and clarify the mechanism due to the difficulty of conducting experiments. The most plausible mechanism for ice crystal icing is that ice particles sucked into the engine melt and form a liquid film on the blade surface, to which new ice particles adhere, decreasing the temperature of the liquid film and finally forming a ice layer [1]. Therefore, the behavior of ice particles impinging on a wall with a liquid film is very important in elucidating the icing mechanism. With the above background, we conducted numerical simulations of ice particle impingement on a wall surface with a liquid water film to investigate the effect of the liquid film on the ice particle impingement. In the preset simuluation, the Moving Particle Simulation (MPS) method [2] and Explicit-Moving Particle Simulation (E-MPS) method[2] were applied to the ice particles and to the liquid film, respectively. We introduced the polygon wall[2] as the wall boundary condition and the potential model of Kondo et al.[3] as the surface tension model. The interaction of each phase was considered using a pressure gradient term. As the computational conditions, the ice particle diameter and initial liquid film thickness were set to 1.9-3.0 mm and 0.45-0.90 mm, respectively. The initial velocities toward the wall were set to 3.0-7.0 m/s in the low-speed condition and 64.5 m/s in the high-speed condition. The simulation results showed that the reduction of the repulsion coefficient due to the presence of a liquid film was reproduced for the impact behavior of ice particles on a liquid film. Moreover, it was found that the repulsion coefficient is primally affected by the initial velocity and the thickness of the liquid film. It was also confirmed that the ice particle breakup behavior was independent of the liquid film thickness under high-speed condition. These results would be useful in developing models that take into account ice particle sticking decisions.