“Cartesian Grid Fluid Simulation with Irregular Boundary Voxels”

There are two grid-based techniques for simulating the motion of fluid: finite difference and finite element. Finite element methods fit a deformed grid to the details of the simulation while finite difference methods impose a regular grid on the simulation details. Most computer graphics CFD solutions have been based on finite difference techniques on regular cartesian grids. These are much easier to implement but details are lost in grid discretization.

Johansen, H., and Colella, P. 1998. A cartesian grid embedded boundary method for poisson’s equation on irregular domains. Journal of Comp. Physics, 147, 60–85.
Losasso, F., Gibou, F., and Fedkiw, R. 2004. Simulating water and smoke with an octree data structure. ACM Trans. Graph. 23, 3, 457–462.