arXiv subjects

Alexis Mérigaud

Publications and source records attributed to Alexis Mérigaud.

3 recordsLinked to original sources

arXiv2026

Jet creation and wave energy dissipation by a submerged elastic plate

Experiments on a flexible plate horizontally submerged in a wave tank are reported in this paper. The plate is held at a fixed depth at its upstream end, while its downstream end is free to move. The wave field is measured using a synthetic Schlieren technique, giving access to an estimate of the fractions of the incoming wave energy that are transmitted and reflected after encountering the region where the plate is submerged. Part of the incoming wave energy is shown to be dissipated by the plate. Flow field measurements in a vertical plane parallel to the wave propagation are performed to examine the wave-plate interaction. A jet-like flow is produced at the free end of the plate, with strong vortex activity similar to that produced by a flapping fin. The kinetic energy present in this jet-like flow is computed from the velocity field measurements, and the external dissipation produced by jet creation is estimated. Results highlight the efficiency of flexible plates in reflecting and attenuating waves. This study also showcases a change in jet direction, in particular the observation of a jet going upward toward the free surface for certain frequencies. Such a configuration, could be of great interest for wave energy conversion applications, while preventing harmful phenomena such as seabed erosion.

physics.flu-dyn↗

arXiv2024

Water wave interactions with a horizontal submerged elastic plate

This article explores how a submerged elastic plate, clamped at one edge, interacts with water waves. Submerged elastic plates have been considered as potentially effective design elements in the development of wave energy harvesters but their behavior in a wave field remains largely unexplored, especially experimentally. Positioned at a fixed depth in a wave tank, the flexible plate demonstrates significant wave reflection capabilities, a characteristic absent in rigid plates of identical dimensions. The experiments thus reveal that plate motion is crucial for wave reflection. Sufficiently steep waves are shown to induce a change in the mean position of the plate, with the trailing edge reaching the free surface in some cases. This configuration change is found to be particularly efficient to break water waves. These findings contribute to understanding the potential of elastic plates for wave energy harvesting and wave attenuation scenarios.

physics.flu-dyn↗

arXiv2021

Ocean wave transmission, reflection and absorption by rows of vertical structures along the coastline

Large arrays of wave-absorbing structures could serve the double objective of coastal protection against erosion and clean, renewable electrical power production. In this work, the principle of an artificial canopy is explored, which consists of vertical structures, arranged in rows parallel to the coastline. Sea waves, which propagate towards the shore, interact with the obstacle rows. A part of the wave energy is reflected back towards the ocean, another part is transmitted to the shoreline, while the rest of the energy is, in theory, available for energy production (although losses, due to viscous effects within the fluid, or imperfect efficiency of the power conversion mechanism, will unavoidably take place). First, a simple geometric representation of the reflection/transmission properties of individual, fixed rows is presented. In the case of moving rows, relationships are drawn between the internal stiffness and damping parameters of the devices, on the one hand, and their reflection, transmission and absorption characteristics, on the other hand. Array properties are then examined, depending on both individual row design parameters and row-to-row spacing values, using the wide-spacing approximation. A numerical case study illustrates the capabilities of the proposed modelling framework, with arrays of vertical, oscillating rectangular plates. The transmitted, reflected and absorbed wave spectra are examined, along with their dependencies on individual oscillator control tuning and array design parameters.

physics.ao-ph↗