Research on the effects of air during flat plate impacting with water using SPH method

The air cushion produced by the interaction of flat bottom structures and fluids is a practical problem, which happens on a moving body such as airplane or ship hitting water. Research on the formation and effects of air cushion improves the accurate measurement of loads on structures, which is a challenge in simulation because it is the interaction among air, water and solid. In this paper, smoothed particle hydrodynamics (SPH) method is used for the simulation. First of all, the SPH simulation results are compared with experimental results. Then, the processes of air cushion formation and impact with water are described carefully. The kinetic energies of air, water and plate are analyzed. Pressure field of water and pressure on the plate show the effects of air, based on the comparison between with-air and without-air SPH simulation. The influences of plate width on the formation of air cushion and acceleration are investigated in the end.