Angular Particle Impact on Metallic Surfaces with Dynamic Refinement SPH

Because of the mesh-less nature of the smoothed particle hydrodynamics (SPH) method, it has been widely used to simulate surface erosion by impact(s) of angular particles. However, previous SPH models usually adopted uniform resolution for the whole computing domain, which is not conductive to achieve a balance between computational efficiency and prediction accuracy. In this study, numerical models for simulating angular particle impact on metallic surfaces are established by using the SPH method. The innovation of this study is that a dynamic refinement procedure is implemented in the conventional SPH model. The critical step of the procedure is to split individual SPH particles according to the plastic strain and the contact force, such that the particle resolution near the impact site is locally refined. The optimal separation parameter and the smoothing distance of the new particles are determined such that the error produced by the refinement in the kernel summation is small. The present model is validated and verified by simulating single and multiple particle impact on OFHC copper targets. Results show that the dynamic refinement procedure increases the prediction accuracy of the erosive crater and saves the computing effort.