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arXiv · 1806.05404

Graded resonator arrays for spatial frequency separation and amplification of water waves

Luke G. Bennetts·Malte A. Peter·and Richard V. Craster
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Abstract

A structure capable of substantially amplifying water waves over a broad range of frequencies at selected locations is proposed. The structure consists of a small number of C-shaped cylinders arranged in a line array, with the cylinder properties graded along the array. Using linear potential-flow theory, it is shown that the energy carried by a plane incident wave is amplified within specified cylinders, for wavelengths comparable to the array length, and for a range of incident directions. Transfer matrix analysis is used to attribute the large amplifications to excitation of Rayleigh--Bloch waves and gradual slowing down of their group velocity along the array.

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Luke G. Bennetts, Malte A. Peter, and Richard V. Craster. 2018-06-14. Graded resonator arrays for spatial frequency separation and amplification of water waves. https://doi.org/10.1017/jfm.2018.648

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