Topic
Wave flume
About: Wave flume is a research topic. Over the lifetime, 1627 publications have been published within this topic receiving 23335 citations.
Papers published on a yearly basis
Papers
More filters
TL;DR: In this article, a numerical wave flume is developed where nonlinear waves of solitary and cnoidal types are generated by use of the Level I Green-Naghdi (GN) equations by a piston-type wavemaker.
Abstract: This study is concerned with the generation and propagation of strongly nonlinear waves in shallow water. A numerical wave flume is developed where nonlinear waves of solitary and cnoidal types are generated by use of the Level I Green-Naghdi (GN) equations by a piston-type wavemaker. Waves generated by the GN theory enter the domain where the fluid motion is governed by the Navier–Stokes equations to achieve the highest accuracy for wave propagation. The computations are performed in two dimensions, and by an open source computational fluid dynamics package, namely OpenFoam. Comparisons are made between the characteristics of the waves generated in this wave tank and by use of the GN equations and the waves generated by Boussinesq equations, Laitone’s 1st and 2nd order equations, and KdV equations. We also consider a numerical wave tank where waves generated by the GN equations enter a domain in which the fluid motion is governed by the GN equations. Discussion is provided on the limitations and applicability of the GN equations in generating accurate, nonlinear, shallow-water waves. The results, including surface elevation, velocity field, and wave celerity, are compared with laboratory experiments and other theories. It is found that the nonlinear waves generated by the GN equations are highly stable and in close agreement with laboratory measurements.
TL;DR: In this paper , a combined floating breakwater-windbreak has been proposed to reduce both wind and wave energies in the sheltered area, and the 1 km-long breakwater has a porous hull with internal tubes to allow free passage of water; thereby further dissipating wave energy.
Abstract: In order to protect fragile shoreline and coastal assets during extreme storms, a combined floating breakwater-windbreak has been proposed to reduce both wind and wave energies in the sheltered area. The 1 km-long breakwater has a porous hull with internal tubes to allow free passage of water; thereby further dissipating wave energy. The deck of the structure is designed to have a slope of 25 degrees facing the upstream side, and arrays of cylindrical tubes are placed on the sloping deck to form a windbreak. A reduced-scale (1:50) model test was carried out in a wave flume to examine wave sheltering performance under significant wave heights Hs = 3.0 m to 7.5 m and peak wave periods Tp = 9.4 s to 14 s sea states. Both regular and random wave conditions with different wave heights were considered. It is found that transmission coefficients ranging from 0.4 to 0.6 can be achieved under tested wave conditions. Porous breakwater hull increases the wave dissipation coefficients and is effective in reducing the wave reflection at the upstream side. The wave run-up length is dependent on the Iribarren number if the reduction induced by vertical freeboard is considered. Based on experimental data, empirical formulae have been proposed to predict the wave run-up responses in regular waves, probability of non-zero wave run-up occurrence, modified Weibull distribution of the wave run-up peaks and extreme wave run-up in random waves.
01 Jul 2022
TL;DR: In this article , a Hydraulic-Control Wave-maker (HCW) was used to generate sinusoidal waves in the small wave flume. But the authors only used a small-scale prototype of the HCW system using a combination motor and screw jack.
Abstract: Abstract This study aims to develop new experimental equipment to generate waves by using a system termed the Hydraulic-Control Wave-maker (HCW). This experimental device can completely mimic vertical flow distribution via an adjustable set of vertical baffles and subsequently permits the study of multiscale and vertically-variable oceanographic flows. First, a small-scale prototype of the HCW system is developed using a combination motor and screw jack. A relationship between motor speed and flow rate is obtained, which shows a linear increase by satisfying mass conservation. Using this relationship, sinusoidal waves in the small wave flume were generated. A scaled-up physical model of the HCW is built with three baffles, including a movable top baffle; solitary waves with various wave amplitudes are generated; laboratory observations are compared to target data for a verification of solitary wave generation.
30 Dec 2018
TL;DR: In this article, the authors investigated the wave field around a rectangular submerged breakwater by means of an experiment in numerical wave flume and compared the results with those obtained making use of the Boundary Element Method.
Abstract: The wave field around a rectangular submerged breakwater is investigated by means of an experiment in numerical wave flume. The results were compared with those obtained making use of the Boundary Element Method. The numerical experiment is carried out to determine the share of the incident wave energy that are reflected, dissipated over the roof of the breakwater, and transmitted in the lee. The wave field before the breakwater (i.e. the quasi standing field) obtained with the CFD simulations is quite similar to that obtained with the BEM. Some relevant differences between the two models arise in the lee of the breakwater, because the wave motion is strongly affected by the dissipation occuring over the breakwater roof by friction and wave breaking. They cannot be foreseen with BEM, being the motion ideal. Their analysis show that the dissipation is more than halves the transmission of energy, despite the relevant submergence of the considerated breakwater.