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Propagation of obliquely incident water waves over a trench

Published online by Cambridge University Press:  20 April 2006

James T. Kirby
Affiliation:
Department of Civil Engineering, University of Delaware, Newark, DE 19711
Robert A. Dalrymple
Affiliation:
Department of Civil Engineering, University of Delaware, Newark, DE 19711

Abstract

The diffraction of obliquely incident surface waves by an asymmetric trench is investigated using linearized potential theory. A numerical solution is constructed by matching particular solutions for each subregion of constant depth along vertical boundaries; the resulting matrix equation is solved numerically. Several cases where the trench-parallel wavenumber component in the incident-wave region exceeds the wavenumber for freely propagating waves in the trench are investigated and are found to result in large reductions in wave transmission; however, reflection is not total owing to the finiteness of the obstacle.

Results for one case are compared with data obtained from a small-scale wave-tank experiment. An approximate solution based on plane-wave modes is derived and compared with the numerical solution and, in the long-wave limit, with a previous analytic solution.

Type
Research Article
Copyright
© 1983 Cambridge University Press

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