Click to inject vortices — watch turbulent cascade and viscous decay
The 2D Navier-Stokes equations in vorticity-stream form: ∂ω/∂t + u·∇ω = ν∇²ω, where ω = ∇×u and u = ∇×ψ with ∇²ψ = −ω. Solved on a grid using finite differences. Click to inject vortex dipoles. 2D turbulence shows an inverse energy cascade (large-scale coherent structures form) unlike 3D turbulence.