I am interested to find out more about the smoke algorithm used by the Smoke Solver. Is there technical documentation or white papers where this is explained in more detail. In general, I would like to know if it uses some type of Navier-Stokes algorithm.

http://www.cfd-online.com/Wiki/Navier-Stokes_equations [cfd-online.com]

These are links to some papers I found online about Houdini's smoke and fluid solvers. They seem to suggest that the incompressible Navier-Stokes equation is used as the base for most of these solvers with tweaks here and there to improve realism, speed and computational power. Also there seems to be three main methods used in Houdini; Smooth Particle Hydrodynamics (SPH), Volume Grid approaches based on voxels and FLIP which is a type of hybrid between a particle based and volume based fluid simulations.

http://www.cescg.org/CESCG-2007/papers/TUBudapest-Horvath-Peter/TUBudapest-Horvath-Peter.pdf [cescg.org]

http://www.peterclaes.be/tutorials/pct_0007.pdf [peterclaes.be]

http://www.fxguide.com/featured/the-science-of-fluid-sims/ [fxguide.com]

Has anyone compared the results of these simulations with a more academic CFD software package like Fluent, ScStream etc?