Numerical aspects of nonlinear wave-wave interactions in operational-wave models

A wave model is used for the prediction of wind-generated waves in oceans. The wave information is necessary for the design and safety of many off-shore and near-shore structures and for the study of ocean surface-related physical processes. Currently, existing operational-wave models use third-generation wave model. There are several physical processes, described as source terms, available in these wave models. Of these source terms, the one due to nonlinear wave-wave interactions plays a vital role in operational third-generation wave models. The exact computation of nonlinear-linear energy transfer is time-consuming and challenging even with modern computers. The models either lack efficiency or accuracy. Therefore, its practical application still remains controversial for operational-wave models. This chapter provides a platform for better understanding of nonlinear wave-wave interactions and their sensitivity to water depth, directional distribution, and resolution.