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Flow over a leading edge with distributed roughness

Published online by Cambridge University Press:  26 April 2006

J. M. Floryan
Affiliation:
Department of Mechanical Engineering, The University of Western Ontario, London, Ontario N6A 5B9, Canada
U. Dallmann
Affiliation:
Institute for Theoretical Fluid Mechanics, German Aerospace Research Establishment, D-3400 Göttingen, FRG

Abstract

An analysis of the flow over a leading edge with distributed roughness is presented. The analysis is focused on a small neighbourhood of the stagnation line. The roughness is assumed to have a small amplitude and to be symmetric with respect to the stagnation line. Results show that roughness acts as a source of streamwise vorticity. The existence of a universal form of the flow field for long-wavelength roughness is demonstrated. It is shown that surface stresses tend to eliminate roughness if erosion or wall flexibility are admitted. The heat flow tends to concentrate at the tips of the roughness and this may lead to the generation of large thermal stresses along the surface of the leading edge.

Type
Research Article
Copyright
© 1990 Cambridge University Press

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