An SPH projection method for simulating fluid-hypoelastic structure interaction

In this paper an incompressible Smoothed Particle Hydrodynamics (SPH) method is proposed for simulation of fluid–structure interaction problems, deploying the pressure Poisson equation to satisfy incompressibility constraints. Viscous fluid flow past rigid and hypoelastic solid surfaces is studied. The fluid is fully coupled with the solid structure that can undergo large structural deformations. A key feature of the proposed scheme is that the no-slip and coupling conditions on the contact surface are satisfied automatically. To alleviate the numerical difficulties encountered when a hypoelastic solid structure is highly stretched, an artificial stress term is incorporated into the momentum equation which reduces the risk of unrealistic fractures in the material. To demonstrate the ability of the proposed method in dealing with large deformation of free surface, the well known pure dam breaking problem is solved and then, the oscillations of an cantilever beam is simulated to show the capability of the method in capturing the large deformations of an elastic solid. Eventually, three challenging test cases, deformation of an elastic plate subjected to time-dependent water pressure, collapse of a water column with an obstacle and breaking dam on a hypoelastic wall are solved to demonstrate the capability of the proposed scheme. The simulated results are in very good agreement with available experimental and numerical results.