Hydrodynamic performance of a Comb-Type Breakwater-WEC system: An analytical study

Abstract

A breakwater-WEC system combining heaving body Wave Energy Converters (WEC) and Comb-Type Breakwater (CTB) was investigated. The traditional CTB consists of a distributed array of separated bottom-mounted caissons and wave chambers are located between two caissons. Heaving bodies provide the power take off (PTO) principles that are located at the wave chamber of the CTB. The interaction of the CTB and WEC was investigated based on the linear potential flow theory. An analytical model has been developed to examine the hydrodynamic performance of CTB-WEC system. The analytical model is validated with results from an experimental study. Results show that an increase in conversion efficiency is observed when the device is located in the aft end of the wave chamber. A high efficiency (i.e., 77.4%) and qualified wave attenuation performance of the integrated system are achieved for the proposed CTB-WEC system. The wave resonance along the incident wave direction in the wave chamber is beneficial for wave energy capturing. Furthermore, it was found that the critical value kc corresponds to the wave resonance, perpendicular to the incident wave direction, out of the wave chamber. The property of efficiency mitigation at regions of k > kc should be avoided while designing such a system.