Hydrodynamical characteristics of wind wave trains of finite amplitude (Q2755219)

The author derives expressions for hydrodynamic wave characteristics such as the wave surface, hydrodynamic pressure and particle velocity fields in weakly irregular and nonlinear large-scale wave groups under sea conditions. These expressions have been derived by using the method of multiple scale expansions starting from the nonlinear boundary value problem. The asymptotic solutions up to the 5-th order in the small parameter (wave steepness) are obtained, and on this basis the nonlinearity, irregularity, 3-D effects of wave trains and the action of wind surface pressure are analysed. For the particular case of free 2-D wave groups practical formulae, useful for the calculations of ship and offshore structure response under the wind wave action, are presented. Moreover, the asymptotics for periodic progressive Stokes waves is presented.