Water wave transmission by an array of floating disks

TL;DR

This study experimentally validates theoretical models predicting water wave transmission through arrays of floating disks, highlighting their accuracy for small waves and low densities, and identifying limitations for larger waves and denser arrays.

Contribution

It provides experimental validation of combined potential-flow and thin-plate models for wave transmission in floating disk arrays, including effects of wave amplitude and disk concentration.

Findings

Models predict wave energy transmission accurately for small-amplitude waves.

Discrepancies occur with large-amplitude waves and high-concentration arrays due to overwash and collisions.

Validation of rigid-body motion predictions for individual disks.

Abstract

An experimental validation of theoretical models of transmission of regular water waves by large arrays of floating disks is presented. The experiments are conducted in a wave basin. The models are based on combined potential-flow and thin-plate theories, and the assumption of linear motions. A low-concentration array, in which disks are separated by approximately a disk diameter in equilibrium, and a high-concentration array, in which adjacent disks are almost touching in equilibrium, are used for the experiments. The proportion of incident wave energy transmitted by the disks is presented as a function of wave period, and for different wave amplitudes. Results indicate that the models predict wave energy transmission accurately for small-amplitude waves and low-concentration arrays. Discrepancies for large-amplitude waves and high-concentration arrays are attributed to wave overwash of the disks and collisions between disks. Validation of model predictions of rigid-body motions of a solitary disk are also presented.