Evaluation of particle‐based smoothed particle hydrodynamics boundary handling approaches in computer animation

Abstract

AbstractBoundary handling is an important aspect of fluid simulation, and several boundary handling approaches exist in smoothed particle hydrodynamics (SPH), which have individual strengths and weaknesses. However, comparing different boundary handling approaches is challenging as there is no common basis for evaluations, that is, no universal set of experiments with quantitative evaluation across different methods, especially within computer animation where many evaluations rely mainly on visual perception. This article proposes a set of experiments to aid the evaluation of the main categories of fluid‐boundary interactions that are important in computer animation, that is, no motion (resting) fluid, tangential and normal motion of a fluid with respect to the boundary, and a fluid impacting a corner. We propose ten experiments, comprising experimental setup and quantitative evaluation with optional visual inspections, that are arranged in four groups which focus on one of the main category of fluid‐boundary interactions. We use these experiments to evaluate three particle‐based boundary handling methods, that is, pressure mirroring, pressure boundaries, and moving least squares pressure extrapolation, in combination with two incompressible SPH fluid simulation methods, namely IISPH and DFSPH, to establish a quantifiable relation between different combinations of boundary handling with simulation approaches and the main categories of fluid‐boundary interactions. Finally, we summarize all results in a rating table and show how our experiments can be used to determine the promising method for specific requirements regarding a given constellation of fluid‐boundary interaction.