A Comparison of Parabolic Equation Models with a Stepwise Coupled Modes Model
Abstract
Parabolic equation calculations are compared with stepwise coupled mode, COUPLE, calculations for a set of runs for which the two models have overlapping capability. The PE calculations were then extended to consider the additional case of refracting sediment. Normal mode start up fields were used in the calculations. PE models have capabilities differing in the areas of wide angle capability, treatment of the ocean bottom and numerical methods. The intent of this paper is to discuss which of these differences are significant. Calculations were performed at 50 hz. Water depths varied somewhat, but averaged about 150m, corresponding to 3 wave lengths at 50 hz. The dependence of depth with range took two forms. The first consisted of smoothly varying linear segments, the second was the same as the first with a number of spike like irregularities added. Differences are discussed in terms of numerical issues and the physics incorporated in the models. Keywords: Ocean acoustic propagation; Viewgraphs.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 31, 1988
- Accession Number
- ADA227768
Entities
People
- James Syck
- Joseph M. Monti
Organizations
- Naval Underwater Systems Center