×

Excitation of trapped water waves by the forced motion of structures. (English) Zbl 1077.76014

The forced oscillations of a structure that supports a trapped mode are studied in the time-domain using asymptotic and numerical methods. Almost any forcing, whether sustained or transitory, will excite the trapped mode, and in the absence of friction it persists for all time. An investigation is also made into the connection between the time- and frequency-domain solutions for both trapping and near-trapping structures. The trapping structure is given as a sequence of perturbations which transform it into two semicircular cylinders, and the time-domain equations are solved for a transient vertical forcing of the structure for each member of the sequence. Numerical estimates of the frequency and decay rate of the oscillations are made from the time-domain calculations.

MSC:

76B15 Water waves, gravity waves; dispersion and scattering, nonlinear interaction
76M20 Finite difference methods applied to problems in fluid mechanics
76M45 Asymptotic methods, singular perturbations applied to problems in fluid mechanics
PDFBibTeX XMLCite
Full Text: DOI