From a vortex gas to a vortex crystal in instability-driven two-dimensional turbulence
From a vortex gas to a vortex crystal in instability-driven two-dimensional turbulence
We study structure formation in two-dimensional turbulence driven by an external force, interpolating between linear instability forcing and random stirring, subject to nonlinear damping. Using extensive direct numerical simulations, we uncover a rich parameter space featuring four distinct branches of stationary solutions: large-scale vortices, hybrid states with embedded shielded vortices …