Accuracy of the Pressure Release Bottom Approximation for Normal Modes in Shallow Water
Abstract
Previous investigators have recognized that an approximation may be made to the eigenfunctions and eigenvalues for a Pekeris waveguide such that the eigenfunctions end in a node at an effective pressure release bottom below the actual bottom. A simple graphical derivation of the approximation is presented and the accuracy of the approximation for the marine sediments found to be typical of bottoms along the continental shelf is investigated. For a water column capable of supporting up to 74 modes, the approximation results in errors in the vertical wave number of less than 0.25 percent for all modes for all bottom types. This modest error indicates that the approximation should be useful in modeling various problems. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1990
- Accession Number
- ADA230011
Entities
People
- Barry I. Barker
- Grayson H. Rayborn
Organizations
- United States Naval Research Laboratory