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Calculation of two-dimensional and axisymmetric bluff-body potential flow

Published online by Cambridge University Press:  29 March 2006

P. W. Bearman
Affiliation:
Department of Aeronautics, Imperial College, London
J. E. Fackrell
Affiliation:
Department of Aeronautics, Imperial College, London Present address: Central Electricity Generating Board, Marchwood Engineering Laboratories, Marchwood, Hampshire, England.

Abstract

A numerical method incorporating some of the ideas underlying the wake source model of Parkinson & Jandali (1970) is presented for calculating the incompressible potential flow external to a bluff body and its wake. The effect of the wake is modelled by placing sources on the rear of the wetted surface of the body. Unlike Parkinson & Jandali's method, however, the body shapes that can be treated are not limited by the restrictions imposed by the use of conformal transformation. In the present method the wetted surface of the body is represented by a distribution of discrete vortices. Good agreement has been found between the pressure distributions predicted by the numerical method and the analytic expressions of Parkinson & Jandali for a ‘two-dimensional’ circular cylinder and flat plate. A flat plate at incidence and other asymmetric two-dimensional flows have also been treated. The method has been extended to axisymmetric bluff bodies and the results show good agreement with measured pressure distributions on a circular disk and a sphere.

Type
Research Article
Copyright
© 1975 Cambridge University Press

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