Level-set based pre-processing algorithm for particle-based methods

Abstract: Obtaining high quality particle distribution representing clean geometry in pre-processing is essential for the simulation accuracy of the particle-based methods. In this paper, several level-set based techniques for cleaning up dirty' geometries automatically and generating homogeneous particle distributions are presented. First, a non-resolved structure identifying method based on level-set field is employed to detect the tiny fragments which make the geometrydirty' under a given resolutions. Second, a re-distance algorithm is proposed to remove the tiny fragments and reconstruct clean and smooth geometries. Third, a static confinement' boundary condition is developed in the particle relaxation process. By complementing the kernel support for the particles near the geometric surface, the boundary condition achieves better body-fitted particle distribution on the narrow region with high curvature. Several numerical examples include a 2D airfoil 30P30N, 3D SPHinXsys symbol, a skyscraper with a flagpole and an inferior vena cava demonstrate that the present method not only cleans up thedirty' geometries efficiently, but also provides better body-fitted homogeneous particle distribution for complex geometry.