A New Modelling Approach to Complex Turbulent Shear Flows
In order to model complex turbulent shear flows, Hinze regards the departure from the eddy viscosity hypothesis as a result of transport of mean momentum by the large structures. His shear stress expression gives qualitatively correct results, however, greatly overestimates the shear stress. In this paper, flow visualization and measurements were carried out in a boundary layer interacting with a wake generated by a thick aerofoil which leads to an idea for improving Hinze’s model, By assuming the departure from the eddy viscosity hypothesis as a result of transportation of the shear stress contained in smaller eddies by the large structures, the present author has arrived at a new shear stress expression. The shear stresses estimated so far are in good agreement with the experiments.
KeywordsBoundary Layer Shear Stress Flow Visualization Large Structure Small Eddy
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