Three-dimensional vortex visualization in stratified spin-up

We present the results of three-dimensional time-dependent numerical simulations of incremental spin-up of a thermally stratified fluid. The fluid inside a vertical cylindrical container of radius R and height 2H is water characterized by the kinematic viscosity ν and thermal diffusivity κ. Initially, its density (temperature) varies linearly with height and is characterized by a constant buoyancy frequency N, which is proportional to the density gradient. The system undergoes an abrupt change in the rotation rate from its initial value Ωi, when the fluid is in a solid-body rotation state, to the final value Ωf. The aim of this contribution is to show the formation of columnar vortices in a high Rossby number spin-up flow.Graphical Abstract