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Unsteady three-dimensional marginal separation, including breakdown

Published online by Cambridge University Press:  26 April 2006

Peter W. Duck
Peter W. Duck
Affiliation:
Department of Mathematics, University of Manchester, Oxford Road, Manchester M13 9PL, UK
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Abstract

We consider a situation involving a three-dimensional marginal separation, where a (steady) boundary-layer flow is on the verge of separating at a point (located along a line of symmetry/centreline). At this point we include a ‘triple-deck’, thereby permitting a small amount of interaction to occur. Unsteadiness is included within this interaction region through some external means. It is shown that the problem reduces to the solution of a nonlinear, unsteady, partial integro system, which is solved numerically by means of time-marching together with a pseudo-spectral method spatially. A number of solutions to this system are presented which strongly suggest that a breakdown of this system may occur, at a finite spatial position, at a finite time. The structure and details of this breakdown are then described.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 220 , November 1990 , pp. 85 - 98
Copyright
© 1990 Cambridge University Press

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