SecondOrder WaveDiffraction by an Axisymmetric Body in Monochromatic Waves
Abstract
An analysis is given for the diffraction of a plane monochromatic incident gravity wave by an axisymmetric structure. The formulation is exact to second order in the sense of a Stokes expansion where wave steepness is the perturbation parameter. The problem is defined in terms of the secondorder velocity potential which satisfies Laplace's equation in the fluid domain and appropriate boundary conditions. In finding the complete solution, we have decomposed the velocity potential into a particular 'lockedwave' component and a 'freewave' component, which satisfy the inhomogeneous and homogeneous freesurface conditions, respectively. Special attention has been paid to finding a particular lockedwave component that exactly satisfied the inhomogeneous freesurface condition, this inhomogeneity being a distinguishing feature of the second order problem. A semianalytical expression for the particular component of the secondorder diffraction potential has been derived. The homogeneous component of the secondorder potential is obtained by solving a boundary integral equation, using a ringsource approach. Numerical results are given for several types of fixed bodies.
 Publication:

Proceedings of the Royal Society of London Series A
 Pub Date:
 July 1997
 DOI:
 10.1098/rspa.1997.0081
 Bibcode:
 1997RSPSA.453.1515E