Physical and Numerical Modeling of Irregular Wave Transformation over a Fringing Reef

Abstract

Two-dimensional laboratory experiments were conducted to investigate cross-shore variations of wave transformation, setup, and breaking phenomena over a fringing reef. Various conditions of irregular waves were generated by changing a water depth, a wave period, and a wave height. A multi-layer Boussinesq model was used to predict the wave transformation and the results were compared to the experimental results. One-layer and two-layer model configurations were selected to figure out and compare the model capability. In the model and data comparisons, both models well predicted the wave transformation characteristics and setups when the nonlinearity was small. However, as the wave nonlinearity increased, two-layer model results were more stable in the wave breaking region than one-layer model results. The results also showed that the broken wave heights finally reached stable conditions on the reef flat section in all cases and the relative stable wave heights (the ratio of the stable wave height to the water depth) were found as approximately 0.56. This data set can be used to benchmark studies for numerical model developers.