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The downstream flow beyond an obstacle

Published online by Cambridge University Press:  21 April 2006

P. M. Naghdi
Affiliation:
Department of Mechanical Engineering, University of California, Berkeley, Berkeley, California 94720 U.S.A.
L. Vongsarnpigoon
Affiliation:
Department of Mechanical Engineering, University of California, Berkeley, Berkeley, California 94720 U.S.A.

Abstract

This paper is concerned with theoretical predictions, given the upstream conditions from a rigid obstacle of arbitrary shape, of the downstream flow beyond the obstacle for an incompressible inviscid fluid sheet under the action of gravity. The fluid sheet flows upstream over a level bottom, continues to flow over (or under) an obstacle leading to a downstream region over a level bottom. In the absence of surface tension, a nonlinear st., ady-state solution of the problem is used to predict the downstream values of the free-surface wave height for the full range of the far-upstream Froude number. The general results obtained are then applied to a special case of fluid flowing over a stationary hump leading to a supercritical flow far downstream and detailed numerical comparison is made with available experimental results, with very good agreement.

Type
Research Article
Copyright
© 1986 Cambridge University Press

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