A 3-D Random Breaking Model for Directional Spectral Waves

A 3-D Random Breaking Model for Directional Spectral Waves. A new directional wave deformation model due to random wave breaking is developed. The model combines the Kweon and Goda's breaking model (1996) for uni-directional wave and the Karlsson's energy balance equation (1969) with its numerical scheme for directional waves. The basic concept of the Kweon and Goda'a model is to let the wave decay factor vary gradually over a certain distance in order to take into account the random wave breaking process. This concept of gradually varying decay factor is employed as the key Parameter of the new model. However, the spreading of breaking and broken waves in a 3-D system of x, y, a is dealt with modification of the wave decay factor after breaking The modification process is calibrated by comparison with two existing models for uni-directional wave breaking. Verifications were made with two sets of experimental data involving 3-D wave breaking phenomena which were investigated by two laboratories, The model is found to be capable of predicting reasonably well the variations of significant wave heights over shoals measured at two laboratories. With an easiness in computation, the present model is promised to be a practitioner's tool in analyzing spectral wave deformation with breaking.