Optimization of a Hybrid Backward Bent Duct Buoy with Point Absorber Based on Kuantan Harbor Ocean Characteristics

Abstract

Wave energy is attractive due to its generosity, sustainability and cleanliness. A combination of an Oscillating Water Column (OWC) and Oscillating Buoy (OB) is an economical approach to harness wave energy. In this work, a hybrid system constising of Backward Bent Duct Buoy (BBDB) and a floating Point Absorber (PA) was investigated. The PA is attached to the front of the BBDB system. The two devices are aligned in the direction of the incident wave, with the PA deployed upstream of the BBDB. The experiment was conducted based on data collected during the northeast monsoon, southwest monsoon, and transition period regarding sea characteristics in a near-shore region of Kuantan harbor. The hybrid BBDB-PA was scaled up to a laboratory scale by Froude scaling to support physical conditions similar to those at specific ocean sites. A series of physical experiments were conducted in a 2D wave flume to understand the effects of wave period and slit length of the hybrid wave energy converter (WEC) system. Compared to the individual devices of BBDB and PA, the hybrid system design provides a higher peak response amplitude operator (RAO) as well as better performance. In addition, the gap length between PA and BBDB was directly correlated to a wavelength corresponding to the theoretical value for the peak-to-trough length at which the maximum wave height occurs. Regardless of the different geometries of the hybrid wind turbines, it was found that the resonant frequency contributes to optimal performance regardless of the characteristics of the hybrid wind turbines. This research recommends the optimization of power generation from the sea to maximize the space in the sea for power generation.