Experimental investigation of different geometries of fixed oscillating water column devices

Abstract

Oscillating Water Columns (OWCs) are some of the most-studied wave energy converters (WECs). Previous work showed that the geometric characteristics of the OWC can play a significant role in the efficiency of the device. In this study, we investigate the behaviour of different designs of OWC making geometric modifications to the classic design of OWC and the U-OWC, initially suggested by Boccotti [1]. The multi-chamber OWCs examined here are fixed on the seabed and have a slit opening at the seaward side. The physical modelling was undertaken in the COAST laboratory of the University of Plymouth. The devices were tested in regular and irregular wave conditions, with and without power take-off (PTO) mechanism, essentially also testing absorbing seawalls.The aim of the study is to present a preliminary comparison related to the geometry of OWCs under some typical wave conditions and suggest potential shape improvements towards an overall optimization of the devices that takes into account both the hydrodynamic efficiency of the OWC and other design aspects, such as the wave run-up. The present study also endeavours to highlight potential benefits from incorporating OWCs in coastal defence as absorbing seawalls.

Implementation and Testing of a Power Matrix-Based Wave Energy Conversion Model and the Effect Simulated on the Wave Field — Case Study of Laguna, Sc, Brazil

“…In an attempt to bring these fields together to improve the understanding of the wave energy harvesting process, a few studies have already tried to either insert actual sea state data as boundary condition for wave energy conversion devices (Ferguson et al, 2017;Vyzikas et al, 2017), or have used simplified approaches to represent the WEC devices in the sea state models (Millar et al, 2007;Smith et al, 2012;Oleinik et al, 2019a).…”

Investigação numérica da descontinuidade geométrica entre a entrada e a saída de um conversor de energia das ondas do mar do tipo coluna de água oscilante

“…À medida que o consumo energético mundial aumenta questões referentes ao ecossistema, energias renováveis e qualidade de vida levam ao estudo de novas formas sustentáveis de geração energética [1]. Pode-se considerar o oceano como uma das maiores fontes de energia renovável presente, tendo diferentes formas de extrai-la.…”

“…A investigação da otimização geométrica de dispositivos conversores de energia das ondas do mar é um tema de pesquisa que permeia muitos trabalhos científicos dentre eles destacam-se alguns autores brasileiros como Gomes (2014) [6], Barbosa (2016) [7] e Martins (2016) [8]. Trabalhos internacionais também já foram realizados, dentre eles destacam-se Vyzikas et al (2017) [1], Rezanejad et al (2017) [5], Elhanafi et al (2017) [9] e Connell et al (2018) [10].…”

Numerical study of fixed Oscillating Water Column with RANS-type two-phase CFD model

“…Realising the insight into the behaviour and hydrodynamic characteristics of a WEC that CFD modelling can provide, the present study aims to validate the open-source robust CFD code OpenFOAM with the wave generation toolbox waves2Foam [24] for the wave-OWC interaction problem against experimental results produced for this scope [25]. The OWC is examined in regular and irregular wave conditions with and without PTO, herein also mentioned as "lid-on" and "lid-off" OWCs, essentially testing an absorbing sea wall.…”