This video presents the result of a numerical simulation on the wake generated by a porous body. The wake flow is simulated by inserting small-scale discrete vortices into a uniform stream, and the colors in the video represent the magnitude of vorticity. The initial flow field is subjected to a small perturbation based on experimental data. The evolution of the wake flow is manifested by the merging and interactions of the small-scale vortices.
The objective of this investigation is to study the merging and inter-action processes of vortices and the formation of large eddies in the flow. Such an investigation is of importance to many flow-related industrial and environmental problems, such as mixing, cooling, combustion and dispersion of air-borne or water-borne contaminants.