A New SPH Boundary Method And Its Application For Free Surface Flow

Smoothed Particle Hydrodynamics(SPH),a kind of Lagrangian meshfree numerical calculation methods,has a huge advantage in dealing with nonlinear complex free surface flow problems,discontinuous physical phenomena and explosion.However,violent pressure oscillation appears when dealing with problems which have complex geometrical boundary using traditional SPH,which will distort the results.Therefore,there is with importance to find a new method to ease the pressure oscillation.SPH method has been widely used in complex free surface flow.However,violent pressure oscillation occurs due to the residual.In this paper,N-S equation and its basic relevant theory in hydrodynamics based on SPH method was presented.Research on the boundary defects of the traditional SPH method has been conducted to simulate complex geometry boundary,which mainly aimed at the boundary defects caused by the traditional mirror ghost boundary method.A new solid wall condition with dummy particals was used,of which the processes of calculation and data arrangement was stated in detail.The numerical simulation of the rectangular tank and the pressure of surface boundary in calm water showed that the method presented in this paper could deal with the pressure vibration efficiently.Finally,numerical simulation of the piston wave-making,sloshing in a tank and Very Large Floating Structure’s fluid resonance in narrow gaps,based on the corrected SPH method in this paper,has verified the feasibility and stability of the relief of pressure vibration.Slamming with solitary and sloshing in tanks with a baffle are the key research,the conclusion of which showed that the corrected method presented in this paper had great improvement compared with the traditional method.