Evolution of the vorticity-area density during the formation of coherent structures in two-dimensional flows

H. W. Capel; R. A. Pasmanter

doi:10.1063/1.1287924

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arXiv · chao-dyn/9908010

Evolution of the vorticity-area density during the formation of coherent structures in two-dimensional flows

H. W. Capel·R. A. Pasmanter

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Abstract

It is shown: 1) that in two-dimensional, incompressible, viscous flows the vorticity-area distribution evolves according to an advection-diffusion equation with a negative, time dependent diffusion coefficient and 2) how to use the vorticity-streamfunction relations, i.e., the so-called scatter-plots, of the quasi-stationary coherent structures in order to quantify the experimentally observed changes of the vorticity distribution moments leading to the formation of these structures.

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H. W. Capel, R. A. Pasmanter. 2000-02-10. Evolution of the vorticity-area density during the formation of coherent structures in two-dimensional flows. https://doi.org/10.1063/1.1287924

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