Journal of Fluid Mechanics

Propagation of obliquely incident water waves over a trench

James T.  Kirby a1 and Robert A.  Dalrymple a1
a1 Department of Civil Engineering, University of Delaware, Newark, DE 19711

Article author query
kirby jt   [Google Scholar] 
dalrymple ra   [Google Scholar] 


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.

(Published Online April 20 2006)
(Received August 30 1982)
(Revised March 18 1983)