P.Franzese, L.Zannetti A modal of dispersion inthe unsteady separated shear flow past complex geometries |
Applied hydromechanics, Vol. 3 (75) ¹ 4, (2001) |
| The chaotic dynamics of separated flows past complex geometries is studied by means of a low order model. The flows are assumed to be rotational and inviscid, and a technique is described to determine the stream functions for linear shear profiles. The geometry considered is a snow cornice, whose edge allows for the separation of the flow and reattachment downstream of the recirculation region. A free point vortex has been added to the flows in order to constrain the separation points to be located at the edge. Unsteadiness is imposed by displacing the vortex from equilibrium. The trajectories of passive scalars continuously released upwind of the separation point and trapped by the recirculating bubble are numerically integrated, and concentration time series are calculated at fixed locations downwind of the reattachment point. The heteroclinic tangle and lobe dynamics of the recirculation region appear to be among the causes of intermittent trapping and release of scalars, in agreement with the simulation performed by higher order models. |
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| TEXT LANGUAGE: Russian |