Numerical Simulation Method For Fluid-Solid Flow

In the simulation of the multi-medium flow, the Ghost Fluid Method (GFM) has been shown to be a simple and efficient interface treating method in which the computation can be carried out as if in the single medium. This method works well for gas-gas problem, but for gas-water and fluid-solid problems, more conservative errors will be incurred due to the large difference of the density and equation of state (EOS), especially for the interaction of shock wave and interface happens when a strong shock impacting on a material interface. In such a situation, the pressure and the velocity may experience a large gradient or sudden jump across the interface. The real Ghost Fluid Method (rGFM) method has been successfully applied to the numerical simulation of gas-water interface and numerical results show that the rGFM method can capture the shock waves and the material interface accurately with less conservation errors. In this paper, the Hydro-elasto-plastic model is employed for solid, we analyze the structure of the solution of one-dimensional Riemann problem for fluid-solid flow and the problem is solved exactly. The rGFM is applied to treat the fluid-solid interface, where the interface boundary condition is defined by constructing and solving a one-dimensional fluid-solid Riemann problem. By doing so, the multi-medium flow can be computed as single medium flow. One- and two-dimensional tests show that the rGFM method works well for fluid-solid interface, the material interface and other discontinuities are captured correctly .