Author(s): Zhenhua Huang; Shijie Huang; Ying-Min Low; Zhixuan Zhang; Juncheng Chen
Keywords: Wave energy conversion; OWC; CFD
Abstract: Most existing studies on wave energy converters (WECs) focused on the hydrodynamics and conversion efficiency of various designs. For the foundation safety of a bottom-sitting WEC, wave-induced scour around the WEC is an important factor to consider. There is a rich literature in wave or current induced scour around circular cylinders or bridge piers; however, published results on the local scour around WECs are scarce. Compared to circular cylinders or bridge piers, bottom-sitting WECs have much more complicated geometry and near-field flow patterns. This study will focus on a bottom- sitting WEC, which is a circular oscillatingwater-column (OWC) integrated with a C-shaped support. A wave-flume test was performed to study the wave-induced local scour around the WEC. Development of the scour hole depth and the final scour hole profile around the bottom-sitting OWC-type WEC are presented. Two-phase (air-water) flow simulations were also performed to reveal the local flow structure and understand the experimental results. Numerical results show that the vortices shed from the two ends of the C- shaped support are responsible for the formation of the scour holes observed around the two ends of the C-shaped support.