Internal wave focusing by annular forcing
نویسنده
چکیده
A linear theory is proposed for the focusing of internal waves generated by the oscillations of a horizontal annulus that is slender, namely of large aspect ratio, but otherwise arbitrary. The theory exploits the separation of scales and is applied to two configurations: a circular torus, and circular Gaussian topography at the ocean bottom. Both complete and partial annuli are considered. Focusing takes place in all cases, irrespective of the criticality of the forcing, implying that horizontal curvature is the key ingredient. The theory compares quantitatively with recent experiments for a torus.
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تاریخ انتشار 2016