Repository logo
 

Nonlinear wave loads on an offshore Oscillating-Water-Column wave energy converter array

Accepted version
Peer-reviewed

No Thumbnail Available

Type

Article

Change log

Authors

Zhou, Yu 
Ning, Dezhi 
Liang, Dongfang 
Qiao, Dongsheng 

Abstract

This paper studies the nonlinear wave loads on a stationary platform that consists of four cylindrical Oscillating Water Column (OWC) Wave Energy Converters (WECs). The nonlinear wave action on the quad-OWC platform was simulated using a 2nd-order time-domain Higher-Order Boundary Element Method (HOBEM). A carefully instrumented experiment was carried out to validate HOBEM simulations. A circular orifice was introduced to model the nonlinear Power Take-Off (PTO) system on the ceiling of the OWC chamber. Subsequently, the sensitivities of the nonlinear wave loads to the incident wave direction and array spacing were investigated. The optimum angle of wave incidence was found to be π/4, i.e., when the quad-OWC platform is diagonally aligned with the incoming waves. A 2nd-order sloshing resonant mode was found inside each chamber of the OWC array, which leads to an increase of the wave loads. A good selection of the column and row spacing contributes to the reduced wave forces on both the front and rear OWC devices. The directions of the wave loads on the front device were analyzed. The rotational-angle peaks of the wave force and moment were always observed at high frequencies.

Description

Keywords

Oscillating water column, Quad-OWC platform, Wave loads, HOBEM, Nonlinear waves

Journal Title

Applied Ocean Research

Conference Name

Journal ISSN

0141-1187
1879-1549

Volume Title

Publisher

Elsevier
Sponsorship
Royal Society (IEC\NSFC\191369)
This work is supported by the National Natural Science Foundation of China (Grant No. 52011530183), LiaoNing Revitalization Talents Program (Grant No. XLYC2002033), Liaoning BaiQianWan Talents Program (Grant No. 2020921007), Joint grant between NSFC and Royal Society (No. IEC\NSFC\191369) and Fundamental Research Funds for the Central Universities (Grant No. DUT21LAB116).