Enhancing particle methods for fluid simulation in computer graphics

We introduce novel methods for enriched Lagrangian fluid simulation in three distinct areas: smoke animation, liquid animation, and surfacing of simulation particle data. The techniques share a common goal, to efficiently enhance realism of natural-phenomena animations in particle simulation framework. Sub-Grid Turbulence adds synthesized small scale detail to large scale smoke simulation. The transport, diffusion and spectral cascade of turbulent energy are captured, whereas they are left unresolved on a typical simulation grid. Ghost-SPH handling of free-surface and solid-boundary conditions in Smoothed Particle Hydrodynamics liquid simulation captures realistic cohesion for the first time and avoids the spurious numerical errors of previous approaches. Ghost particles are carefully seeded in the air and solid regions near the fluid and are assigned with extrapolated fluid quantities to reach correct boundary conditions. The Beta Mesh is a new method for reconstructing mostly temporally coherent surface meshes from particles representing the volume of a liquid. While current particle surfacing techniques address the geometrical characteristics of the surface, the focus in Beta Mesh is producing a surface which varies smoothly in time, outside of topological changes, while preserving essential geometrical properties.