Trapped modes supported by submerged obstacles
نویسندگان
چکیده
In this paper trapped modes are shown to exist for a pair of bodies which are submerged in deep water. An inverse procedure is used whereby a flow which represents a local oscillation is constructed and closed streamlines which surround the singularities of the flow are interpreted as body boundaries. The velocity potential for the flow is constructed from a symmetric combination of horizontal and vertical dipoles. This combination of singular solutions of Laplace’s equation satisfies the free surface boundary condition and the spacing of the singularities is chosen so that there is no radiation of waves to infinity. The existence of closed streamlines which surround the singularities is demonstrated by investigating how the structure of the streamlines varies as the parameters of the flow change.
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