Abstract
The paper describes in detail a relatively sophisticated numerical approach, using the Boundary Element Method in conjunction with the Discrete Vortex Model, to represent the complex unsteady flow field around a bluff body with separating shear layers. Important steps in the numerical analysis of this challenging problem are discussed and a performance evaluation algorithm established. Of considerable importance is the effect of computational parameters such as number of elements representing the geometry, time-step size, location of the nascent vortices, etc., on the accuracy of results and the associated cost.
As an example, the method is applied to the analysis of the flow around a stationary Savonius rotor. A detailed parametric study provides fundamental information concerning the starting torque time histories, evolution of the wake, Strouhal number, etc. A comparison with the wind tunnel test data shows remarkable correlation suggesting considerable promise for the approach.
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Communicated by S. N. Atluri, January 27, 1989
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Fernando, M.S.U.K., Modi, V.J. A numerical analysis of the unsteady flow past bluff bodies. Computational Mechanics 6, 11–34 (1990). https://doi.org/10.1007/BF00373796
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DOI: https://doi.org/10.1007/BF00373796