Vortex Dynamics
Point vortices in 2D move under the Biot-Savart law: each vortex induces a velocity field that advects all others. This is an exact solution to the 2D Euler (ideal fluid) equations.
Co-rotating vortices orbit each other and may merge — a key mechanism in 2D turbulence's inverse energy cascade.
Kelvin's circulation theorem: total circulation Γ = Σ κᵢ is conserved in ideal flow.
Colors: red = positive (CCW), blue = negative (CW). Background shows induced vorticity field. Click to add a vortex.