Whirlpool Vortex Simulator (2D)

This 2D simulator models a whirlpool as a Rankine combined vortex: a rigid-body core surrounded by a potential-vortex region where tangential speed times radius stays constant, the same angular-momentum conservation that speeds up draining bathwater. The free-surface depression is computed from a real centrifugal-balance equation, integrated numerically to produce the parabolic bowl near the center and the steep funnel wall at the core boundary. Floating tracers spiral inward under mass-conserving radial inflow and visibly accelerate as they near the drain. Adjust the outlet flow rate to control vortex strength and funnel depth.