DNS Simulation of Dry Thermals

The two animations below show the vertical velocity (left panel) and density perturbation (right panel) of a dry, buoyant parcel (or "thermal") rising through a neutrally stratified environment, for both laminar and turbulent cases (left and right animations, respectively). The black line defines the thermal's control volume, and is defined such that the average vertical velocity within equals the velocity of the thermal's top. These are 2-D cross sections of fully 3-D simulations, performed with Dedalus. The mixing or "entrainment" of environmental fluid into these thermals, and its effect on their dynamics, is studied in Lecoanet and Jeevanjee (2019) and McKim, Jeevanjee, and Lecoanet (2019).