Hemming Andreas Schäffer


Among the wide range of potential applications of the convolution-type approach to deterministic wave modeling, this paper looks into the challenge of complex shaped domains. The canonical case of diffraction around a semiinfinite vertical barrier, the ‘Sommerfeld diffraction’ case, is first studied. Focusing on locally constant water depth, the convolution method is related to a boundary integral representation by which the impulse response function representing the convolution kernel is related to a Green’s function for the Laplace equation. This provides a framework for determining the impulse response function by solving a local, three-dimensional Laplace problem prior to the time-stepping of the wave transformation problem. For the Sommerfeld case, numerical results for the impulse response function near the barrier are computed numerically and compared with an analytical solution. For complex-shaped domains, numerical determination of the impulse response functions is the only solution. A very preliminary example of application to wave disturbance in a real port is given.


convolution-type model; wave agitation; diffraction; Sommerfeld; boundary integral equation

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