Interactive fluid flow simulation in computer graphics using incompressible smoothed particle hydrodynamics

Interactive simulations of fluids flow play an important role in several computer graphics-based applications such as computer games, computer animation, movie industry, and virtual realities. The incompressible smoothed particle hydrodynamics (ISPH) model is a promising numerical scheme for large-scale and large-deformation simulations, where the pressure can be determined precisely by solving pressure Poisson equation (PPE). The three main shortcomings of the ISPH scheme are oscillating pressure, particles disorders, and particles penetrations through rigid boundary. In this paper, the stable pressure is obtained from modifications in the source term of PPE, in which the divergence-free velocity condition plus density-invariance condition multiply by a relaxation coefficient are included. The particles disorders are solved via utilizing a shifting technique with the current treatment of source term in PPE. Additionally, the dummy boundary particles are used for the rigid boundary treatment. For getting enough pressure on the boundary, the Neumann boundary condition is satisfied during the implicit solving processes. The performance of the stabilized ISPH model is tested on various numerical simulations with largely distorted free surface including liquid sloshing problems, fluid-fluid and fluid-structure interactions, and dam-break flows. To extend the applicability of the stabilized ISPH model, the post process including visual realism with a highly rendering scheme is coupled. The coupled scheme introduces several simulations including free falling of a rigid body, water splashes, and dam break analysis. Furthermore, the proposed ISPH-based method enables efficient and viscous fluid simulations with large time steps, higher viscosities, and resolutions, and it is a robust scheme in long interval simulations of nonlinear free-surface flows.