Normal Mode Propagation in a Wedge

date December 5, 1985
comments no comments.

Thursday, December 5, 1985 3:30 p.m.

C. T. Tindle
Applied Research Laboratories
on leave from
University of Auckland
Auckland, New Zealand

Exact theoretical descriptions of acoustic propagation in shallow water are restricted to horizontally stratified situations. There are no exact descriptions for propagation over a sloping bottom.

Experimental measurements have been made in an indoor tank. Individual, low order normal modes can be excited by a line source.

Results show that propagation takes place as “wedge modes” which are similar to normal modes for constant water depth but their wavefronts are curved to suit the geometry of the wedge. The wavefronts are arcs of circles centered on a wedge apex.

Background theory and experimental results will be described.