Von Karman Vortex Street behind a flat plate (Laminar).mov

A Von Karman Vortex Street forming behind a flat plate in a 2D channel. The Navier-Stokes equations were solved here using the semi-Lagrange method (for the advection terms) with Helmholtz decomposition (for the pressure field), as outlined in the paper ’Stable Fluids’ by Jos Stam (1995) (and various others by the same author). Some vorticity confinement was used to compensate for false diffusion. The Reynolds number based on plate length is 80, but this is not to be used for any strict comparison due to the use of vorticity confinement and false diffusion. The stable fluids solution paradigm is not really intended for scientific purposes, but rather for real time good-looking stuff. It is a fully implicit first order in time, second order in space method. Thus it never ’blows up’ and is therefore attractive for use in games where absolute precision is not really an issue. Colouration is based on the concentration of a passive scalar advected by the flow (i.e. dye / smoke injection). The channel walls are