Test and Evaluation of an Improved Sea, Swell and Surf Program.
Abstract
In this thesis a sea, swell and surf program is improved, tested and evaluated on a micro-computer (HP-9845B). Sea swell is calculated by a two dimensional spectral model. The energy balance equation is tested for different cases of wind velocities and water depths. Satisfactory agreement is observed between the offshore model and expected wave heights for a 15 knot wind, but the model overbuilds wave energy for a 30 know wind. Wave transformation is described by a one dimensional random wave model in which the wave heights are described by a one dimensional random wave model in which the wave heights are described using the Rayleigh distribution. The obtained solution of the random wave field is used to predict the longshore currents. An empirical formula for determining the breaker parameters is developed, based on beach slope and incident wave steepness. The improved model is tested using an undulated bathymetry to validate the model physics. The model outputs of wave height and current are compared with data acquired from a wave tank and natural beaches. The model is found to accurately forecast wave heights, breaker location, breaker type and longshore currents for several sets of conditions. Model limitations are discussed and recommendations for further improvement are made. Keywords: Sea; Swell; Surf; Wave prediction; Surf prediction; Breakers; Wind generation; Longshore currents.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1985
- Accession Number
- ADA161023
Entities
People
- Michael J. Gill
Organizations
- Naval Postgraduate School