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Laminar flow over unsteady humps: the formation of waves

Published online by Cambridge University Press:  20 April 2006

P. W. Duck
P. W. Duck
Affiliation:
Department of Mathematics, University of Manchester, Manchester M13 9PL
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Abstract

Both the incompressible and supersonic laminar flow over a small, unsteady hump are considered. The Reynolds number is assumed large, and the analysis is based upon triple-deck theory. In the incompressible case disturbances tend to grow downstream, as a result of triggering the Tollmien–Schlichting mode of instability. For the supersonic case the flow disturbances tend to decay downstream across the entire frequency spectrum. However, for sufficiently large humps a seemingly catastrophic failure of the governing equations may occur, our results suggesting that this is caused by an inviscid, short-scale, Rayleigh type of instability.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 160 , November 1985 , pp. 465 - 498
Copyright
© 1985 Cambridge University Press

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