A novel smoothed particle hydrodynamics method for multi-physics simulation of laser powder bed fusion

In this work, we propose an efficient smoothed particle hydrodynamics (SPH) method for simulating laser powder bed fusion (LPBF). The multi-physics process of LPBF, including the heat transfer and phase change with complex boundaries, is accurately resolved by a novel heat source model and a modified continuous surface force based on a corrected surface delta function. Moreover, we also develop an efficient tensile instability control algorithm for preventing the pressure oscillations. The present method is implemented in a GPU-accelerated framework, and its performance is well demonstrated by simulating the LPBF processes with both single-layer and multi-layer powder beds (with the help of surface reconstruction). The numerical results are compared well with the experimental ones which clearly verify the ability of the present method in capturing the complex physical phenomenon of LPBF.