Interactive Fluid-Particle Simulation using Translating Eulerian Grids

"Interactive Fluid-Particle Simulation using Translating Eulerian Grids"
Jonathan Cohen, Sarah Tariq (NVIDIA), Simon Green (NVIDIA), in Interactive 3D Graphics and Games (I3D) 2010, February 2010
Research Area: Computational Fluid Dynamics
Author(s): Jonathan Cohen, Sarah Tariq (NVIDIA), Simon Green (NVIDIA)
Date: February 2010

We describe an interactive system featuring fluid-driven animation that responds to moving objects. Our system includes a GPU accelerated Eulerian fluid solver that is suited for real-time use because it is unconditionally stable, takes constant calculation time per frame, and provides good visual fidelity. We dynamically translate the fluid simulation domain to track a user-controlled object. The fluid motion is visualized via its effects on particles which respond to the calculated fluid velocity field, but which are not constrained to stay within the bounds of the simulation domain. As particles leave the simulation domain, they seamlessly transition to purely particle-based motion, obscuring the point at which the fluid simulation ends. We additionally describe a hardware-accelerated volume rendering system that treats the particles as participating media and can render effects such as smoke, dust, or mist. Taken together, these components can be used to add fluid-driven effects to an interactive system without enforcing constraints on user motion, and without visual artifacts resulting from the finite extents of Eulerian fluid simulation methods.