A Harbor Ray Model of Wave Refraction‐Diffraction
Publication: Journal of Waterway, Port, Coastal, and Ocean Engineering
Volume 111, Issue 1
Abstract
A harbor ray model has been developed which describes the combined wave effects of diffraction around breakwaters and depth refraction. Ray models are computationally well suited to determining the response of large harbor areas to short period waves. This is a situation for which alternative mathematical models can use prohibitively large amounts of computing time and storage. Diffraction caused by two types of breakwater layout, commonly found at harbor entrances, is shown to be capable of being modeled by a ray method. These breakwater layouts are: (1) A small gap between two straight breakwaters; and (2) a single, straight, semi‐infinite breakwater. A new ray system is presented for the semi‐infinite breakwater problem which overcomes the difficulty of modeling the region around the geometric shadow boundary. Unlike other techniques developed to resolve this difficulty, this method retains a ray plotting solution technique and therefore keeps the computational advantages of such a technique. A comparison is made between the ray model and a finite‐element model for the two breakwater layouts on constant‐depth and sloping sea‐beds.
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Copyright © 1985 ASCE.
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Published online: Jan 1, 1985
Published in print: Jan 1985
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