1. A computer-implemented method for simulating a fluid flow, the method comprising: dividing a fluid into a plurality of coarse voxels at a first resolution; simulating the fluid flow associated with each coarse voxel in the plurality of coarse voxels at the first resolution; defining a three-dimensional window that includes a portion of the coarse voxels; dividing each coarse voxel in the portion of the coarse voxels into a plurality of fine voxels at a second resolution; simulating the fluid flow associated with each fine voxel in the plurality of fine voxels at the second resolution, based at least in part on the simulation at the first resolution.