Improvement And Verification Of The Surface Detail Algorithm Of Fluid-Solid Interaction Based On Material Point Method

The simulation of fluids-solids interaction has always been a challenging and extremely important topic in computer graphics.Since fluid-solid interaction involves complex topological changes,it requires sophisticated numerical methods in order to obtain visually realistic and numerically accurate results.The surface details and computational efficiency of fluid-solid interaction are the hot research areas.Firstly,in order to deal with the drastic changes in the topology during the interaction between fluid and solid,the paper adopts a hybrid particle-grid material point method.And the Interface Quadrature and ghost matrix of the contact surface are introduced to eliminate numerical viscosity and realize the free slip effects of the solid particles.Secondly,the hierarchically background grid is introduced to improve the surface details in the fluid-solid interaction and solve the problem of the large amount of particle-grid information transfer of the material point method.The finer grids are used for the surface area of fluids and solids,and the coarser grid is used for the internal area.the hierarchical grid is used to reduce the number of particles and improve calculation efficiency.By introducing the adaptive generalized interpolation method,more particles are sampled in the surface area,which greatly improves the surface details of fluid-solid interaction.Next,the paper introduces an APIC narrow band method to enhance the calculation efficiency in fluid-solid interaction.The method analyses the characteristics of the solid motion process and finds that the solid has little topology changes and has no contribution to its surface reconstruction.Thus,the solid surface is reconstructed with narrow band particles,and Euler grids are used to represent the interior of the solid.The narrow band region is realized by the level set function and particle resampling,which greatly improves the overall operating efficiency.Then,the surface reconstruction technology is improved and optimized.Based on the basic principles of the traditional surface reconstruction algorithm,the VDB method is used to construct volumetric data according to the position information.Multi-threading technology can be used to convert particle models into polygonal mesh models in parallel to facilitate subsequent rendering operations.Finally,we utilize Taichi graphics language to build the basic environment for fluid-solid interaction.We also design multiple interaction scenarios and comparison experiments to verify the effectiveness of our methods.