ABSTRACT
The study of wave-structure interaction has important applications in coastal and offshore engineering. Although part of the study is to understand the fundamental flow characteristics and wave scattering during wavestructure interaction, most of the study has a goal of finding the wave load on a structure, from which the structure response and stability can be analyzed. The total flow force on a body can be theoretically obtained by surface
integration of pressure and stress on the body, which is, however, difficult to measure directly in practise. In most of the engineering designs, the simple empirical or semiempirical approach such as the Morison equation or the Froude-Krylov (F-K) method is employed. Only in the last two decades, as computer power has rapidly increased, has the direct modeling of wave-induced pressure and/or stress become possible for practical design purposes. This chapter will provide an introduction to various engineering modeling techniques used in a wide range of wave-structure interaction studies. In general, both pressure and viscous stress under waves are depth-
dependent unless the wavelength is very long. Besides, most of the coastal or offshore structures have the surface configuration that is also depthdependent. This implies that in order to accurately model wave loads on a structure, the depth-resolved wave models must be used. In addition, since the vertical acceleration may become significant during wavestructure interaction along the vertical surface of the body, the models must be capable of simulating nonhydrostatic pressure. Searching the category of wave models discussed in Chapter 5, we find that for general wavestructure interaction modeling only two types of models are valid candidates, namely the potential flow models for inviscid and irrotational flows and the NSE models for viscous and turbulent flows. The depth-averaged models, e.g., MSE models, SWE models, and Boussinesq models, may be used only if the focus of the study is on wave scattering rather than wave loading.
