Improving SPH Fluid Simulation Using Position Based Dynamics

Physical-based simulation technique has been widely used in creating astounding fluid appearances for film industries and computer games. However, stable and realistic fluid simulation based on Smoothed Particle Hydrodynamics (SPH) method is still challenging, as unstable solid boundary handling and numerical dissipation always plague current SPH fluid solvers. To solve these issues, we present a new method for improving SPH fluid simulation using position-based dynamics (PBD). For the stable fluidsolid interaction, by combining the position constraint solved by PBD and the relative contribution of solid boundary particles, we significantly alleviate the penetration issues at fluid-solid interfaces. And in order to stably simulate turbulence diffusion of SPH fluids, we enforce a novel nonlinear vorticity constraint on each fluid particle, and then solve it using PBD to smooth the vorticity field. The implementation results demonstrate that our method significantly improves SPH method for simulating realistic and stable animations of fluid phenomena.