A Numerical Study of a Stably-Stratified Mixing Layer
The dynamics of a stably-stratified unstable mixing layer are studied using three-dimensional direct numerical simulations. The effects of the stable stratification on the two- and three-dimensional instabilities, on the vorticity dynamics, and on the flow energetics are analyzed. In particular, the behavior of the flow in the later stages of decay, when the effects of stratification have become dominant, are investigated. It is found useful to then interpret the flow in terms of propagating (internal wave) and nonpropagating components, the latter associated with the potential vorticity of the flow.
KeywordsInternal Wave Potential Vorticity Richardson Number Vertical Vorticity Stratification Effect
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