Abstract: Two methods(SPH and ALE) are used to simulation of droplets impacton PMMA.Deformation of droplets and failure of PMMA are compared.It shows that the surface failures in two methods agree with Brunton's experiment.Feasibility and accuracy of two methods are proved.SPH method shows better ability in simulating liquid-solid impact.Then,a rain ball impact the edge of airscrew of a flying aircraft is analyzed with SPH method.Two engineering techniques are proposed to protect integrity of airscrew.

Key words: liquid-solid impact, SPH, rain, airscrew