Stability and Detail Improvement Method for SPH Volume Maps Fluid-Solid Interaction

Aiming at the stability problems and the poor fluid details of the existing smoothed particle hydrodynamics (SPH) fluid-solid interaction methods, an improved fluid-solid interaction method based on volume maps was proposed. Firstly, the divergence-free SPH method was used to model the fluid to enforce the incompressibility. Secondly, the volume maps method was introduced to handle the solid boundary, and the boundary was represented by implicit functions instead of particles to solve the problem of the bumpy solid surface with particle sampling method. Then, Moving Least Squares was introduced to interpolate the pressure on the solid boundary to avoid the error caused by the pressure mirroring, which improved the accuracy of the pressure and pressure gradient in the volume maps, and improved the system stability. Finally, the particle resampling method was introduced to refine the fluid surface to fully show the different particle characteristics of the fluid surface regions, which enhanced the fluid details after fluid-solid interaction and the reality. The experiments used the basic three-dimensional models provided by Stanford University. The experimental results show that this method can truly and stably simulate the interaction of incompressible fluids and solids, handle complex scenes with multiple static or dynamic solids, and effectively represent fluid details.