Wave flume

About: Wave flume is a research topic. Over the lifetime, 1627 publications have been published within this topic receiving 23335 citations.

Laboratory investigation on wave reflection characteristics of suspended perforated pipe breakwater

Abstract: A laboratory investigation on the suspended perforated hollow cylinders in a single row was conducted in a two-dimensional wave flume, to study their hydraulic performance. The influence of depth of submergence, size of pipes, percentage of perforations and water depth on wave reflection characteristics have been investigated. From the investigation it was found that, as the relative depth of submergence increases, reflection increases. Water depth has insignificant effect on reflection coefficient Kr. The reflection coefficient Kr increases as incident wave steepness increases. For perforated pipes, size of the pipe has negligible effect on Kr. Wave period alone does not directly influence the reflection.

Wave Generation And Active Absorption In a Numerical Wave Flume

Abstract: A numerical wave flume is simulated using a Boundary Element Method (BEM) model combined with a time stepping procedure. The boundary conditions in the BEM are similar to those in a physical wave flume, e.g. with a wavemaker at one end boundary and an absorbing condition at the other. The free water surface is described by two nonlinear boundary conditions, and the sea bed by a no-flux condition. Active absorption by a wave paddle is used for eliminating outgoing waves at the two ends of the wave flume. These waves are: I) the progressive waves propagating towards the outflow boundary, and 2) the waves coming back to the generation boundary due to reflection from the outflow boundary. The method used at the Danish Hydraulic Institute for simultaneous generation and active absorption of waves in flumes is implemented as boundary conditions and tested for regular as well as irregular waves. Comparison with theoretical prediction of absorption coefficients shows good agreement. Although the active absorption system has previously been successfully tested in a physical wave flume, the numerical flume provides an attractive tool for further

Numerical simulation of propagation and breaking processes of a focused waves group

Abstract: A two-dimensional numerical wave flume is developed to study the focused waves group propagation and the consequent breaking processes. The numerical model is based on the Reynolds-Averaged Navier-Stokes (RANS) equations, with the standard k-e turbulence model to simulate the turbulence effects. To track the complicated and broken free-surface, the Volume Of Fluid (VOF) method is employed. The numerical model combines the “Partial Cell Treatment (PCT)” method with the “Locally Relative Stationary (LRS)” concept to treat the moving wave paddle so that various waves can be generated directly in a fixed Cartesian grid system. The theoretical results of the linear and nonlinear waves are used to validate the numerical wave flume firstly, and then a plunging breaking wave created by a focused waves group is simulated. The numerical results are compared to the experimental data and other simulation results, with very good agreements. The turbulence intensity, the flow field and the energy dissipation in the breaking processes are analyzed based on the numerical results. It is shown that the present numerical model is efficient and accurate for studying the waves group generation, the waves packet propagation, and the wave breaking processes.

A model for cross shore sediment transport

Abstract: In this paper a mathematical model for the computation of the cross shore sediment transport for random waves is presented. The model consists of the hydrodynamic, the suspended sediment transport and bed load modules. The suspended sediment concentration is computed with the use of the wave-averaged convection diffusion equation. The vertical structure of both the wave-induced current and suspended sediment concentration are modelled with the use of quasi-3d techniques. Mechanisms for the offshore transport (undertow) and the onshore transport (Lagrangian transport, transport due to wave asymmetry) are included. The model is tested against an experiment with random waves at prototype scale.

Inner Harbor Wave Conditions due to Breakwater Overtopping

Abstract: The results of this study have important application to the design of small boat marinas protected from incident waves by breakwaters that may be overtopped during extreme wave events. This overtopping results in transmitted waves with significantly different characteristics than the incident waves. Experiments were conducted with two different breakwater sections, regular and irregular waves, and with several depths representing storm surge effects. It was found that the spectra of the transmitted waves are generally quite different in total energy and in the frequency-wise distribution of the energy compared to the incident wave spectra. The important frequencies associated with the transmitted wave are up to twice that of the incident waves. The transmission characteristics for both regular and irregular incident waves are best defined by the root mean square of the wave amplitudes.