Wave flume

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

Understanding and modelling wave-driven mixed sand transport

Abstract: This paper presents new net transport data from the STENCIL full-scale wave flume experiments with a sediment mix of a fine (0.21 mm) and a coarse (0.58 mm) sand fraction. These and existing mixed sand transport data from full-scale oscillatory flow tunnel experiments were used to validate the SANTOSS practical sand transport formula, which includes size-selective transport mechanisms and hiding and exposure effects. The STENCIL data show a strong effect of the sediment mix on the bed form regime and net transport rates. The SANTOSS formula predicts the flow tunnel net sand transport data well, and does a reasonable job in reproducing the net sand transport per fraction in the mix. The new STENCIL net transport data are generally underpredicted. In further research the SANTOSS formula will be further tested and improved using more detailed STENCIL data of flow and sand transport processes.

Large-scale simulation test system simulating combined effects of earthquakes, waves and ocean currents

Abstract: A large-scale simulation test system simulating combined effects of earthquakes, waves and ocean currents belongs to the marine structure dynamic test technical field. The simulation test system comprises a test wave flume, an absorption type wave making apparatus, a test water circulation apparatus, a speed-adjustable pulley platform, an earthquake simulation apparatus, a bidirectional-flow simulation apparatus, and a water-resisting sealing apparatus. The upper plane of a vibration table body of the earthquake simulation apparatus is aligned with the bottom plane of the test wave flume. The water-resisting sealing apparatus is arranged between the periphery of the vibration table body upper plane and the bottom plane of the test wave flume. The absorption type wave making apparatus is arranged on the head end inside the test wave flume. A flow-making pump of the bidirectional-flow simulation apparatus is connected with head-end current-sharing cases and tail-end current-sharing cases through pipelines. The system with complete test simulation functions can simulate different input excitation test conditions of a marine structure under various load combination effects. Test simulations of earthquakes, waves and ocean currents are all controlled in a full-digital way. The system further has the characteristics of high control precision and diversified test functions.

Numerical Simulation of Velocity Fields and Vortex Generation around the Submerged Breakwater on the Sloped Bottom

Abstract: The study of velocity fields and vortex generation around the submerged breakwater can be utilizedas materials related to understanding of wave disipation mechanism, sediment transport, and stability ofstructure. In the present study, two-dimensional numerical wave flume, based on the VOF method to trace fresurface, developed by Kim et al.(2001, 2002) was used to numericaly simulate velocity fields and vortexgeneration around the impermeable submerged breakwater instaled at the uniform botom. Especialy, thecharacteristics of vortex generation due to the geometry of the structure and incident wave conditions areexamined through the analysis of averaged-velocity fields around the impermeable submerged breakwater. Fromthe numerical simulations, it is confirmed that a counter clockwise vortex is formed in front of the structure anda clockwise vortex develops behind the structure. Also, incident wave height and period have an sensitive effecton the strength of vortex.

Free surface numerical modelling of wave interaction with coastal structures

Abstract: The main objective of Workpackage 5 is to use numerical simulation of wave overtopping in order to solve the problem of suspected scale effects. A second, related, objective is to improve existing codes in such a way as they are able to simulate wave overtopping in a reliable way. The final, single, objective is to numerically model long waves on the shallow foreshore at Petten in order to understand the phenomenon of long waves and their effect on overtopping. This report deals with the work undertaken towards the first two objectives, the simulations undertaken for objective 3 are the subject of a separate report entitled “Influence of low-frequency waves on wave overtopping” by M.R.A. van Gent and C.C. Giarrusso and published by WL | Delft hydraulics in November 2003. Realistic simulations of wave overtopping require numerical methods which are able accurately to simulate the shoaling, breaking and possible overturning of waves prior to their impact on the seawall. It is a further requirement that the simulation continues after impact, modelling the formation of the overtopping jet and the reflection of the wave. The research groups at Manchester Metropolitan University (MMU) and the University of Gent (UGent) have been working in parallel on the development of such numerical codes. The MMU code, AMAZON-SC, is a numerical wave flume based on the free surface capturing approach. While the UGent code, LVOF, is a numerical wave basin based on the volume of fluid approach. This report describes the progress of these numerical methods, in order to address the first two objectives of Workpackage 5. Their application to various cases, is also discussed, including: a test problem involving wave overtopping of a smooth sea-dike, wave overtopping at Samphire Hoe and an investigation of scale effects on rough impermeable structures. The Report begins with a general introduction, followed by a section describing AMAZONSC (the MMU code), a section describing LVOF (the UGent code) and then some general conclusions.

Oscillating water column wave pump: a wave energy converter for water delivery

Abstract: The research presented in this dissertation investigates the development and the performances of a new type of Wave Energy Converter (WEC) aimed to provide water delivery and energy storage in the form of potential energy. The Oscillating Water Column Wave Pump (OWCP) concept was proposed and tested through a series of experimental investigations supported by scientific theory. The OWCP was developed after an extensive study of the existing wave energy technology available, from which it emerged that the Oscillating Water Column (OWC) device could be further implemented for water delivery purposes. The existing theory of the OWC was employed to develop a mathematical theory able to describe the system wave response and water removal of the OWCP. In order to understand and validate the mathematical models of the OWCP, experimental investigations were carried out under the influence of incident linear waves in a two-dimensional (2D) and three-dimensional (3D) wave flume. The experimental equipment and methodology are outlined, including the description of wave flumes, models and data acquisition equipment. Experimental tests were used to verify the concept of the OWCP and assess its performances, investigating both the response of the device to the waves with and without water removal. In order to increase the efficiencies of delivery, array configurations of multiple OWCPs were adopted. The research demonstrated that up to 14% of the energy carried by the incoming waves can be converted into useful potential energy for a single device. Moreover a further increase of the efficiencies can be obtained with the array configuration improving the overall capability of the OWCP, for optimal separation distance between the array components. Further model tests are required to extended this research to validate the developed mathematical models as an effective prediction tool of the performances of the OWCP and further increase the efficiency of water removal that can be achieved.