27 of 1,681 Voxels Flipped Inside Out — Ray Parity and Link Cutting in STL Voxelization
·10 min read
Turning an STL into an LBM voxel grid takes four stages: octree culling, SAT overlap tests, ray parity, and the per-link cut fraction q, verified in code.
Three at a wall, five at a corner — counting the populations an LBM boundary node loses
·7 min read
After streaming, the number of empty populations at a lattice-Boltzmann node equals the number of solid cells around it: three on a flat wall, five in a concave corner, one on a convex corner.
In Lattice Boltzmann, the Wall Isn't on the Node — Bounce-Back and Zou-He Boundaries
·5 min read
The bounce rule that builds a no-slip wall, and where that wall really sits