The M3 pressure-differential wave energy converter in Persian shores; numerical modeling and design

Abstract

Following a double objective, this paper develops a numerical model for the M3 fixed-bottom pressure-differential wave energy converter (WEC) and then employs the model in the design of the WEC with available wave data for three Persian shores. To reach the first objective, using the potential theory, a simple numerical method, based on the conventional finite element method (FEM), has been developed for calculating the added mass and damping coefficients of the WEC. This paper shows that a complex engineering problem can be solved easily by making adjustments and making simple assumptions. These assumptions, though some of which may not be applicable to other types of WECs, are shown to be very effective in the modeling of the WEC considered in this paper. By comparing the results of the proposed method with those previously reported in the literature, the obtained results are validated. With a simple and practical numerical tool in hand, on the sequel and as the second objective, the energy absorption of the WEC is investigated based on the wave data in the Persian Gulf and the Gulf of Oman. For this purpose, several cases are considered for the dimensions of the WEC. Other effective parameters on the energy absorption of the WEC, i.e. the stiffness and damping coefficient of the power take-off (PTO) system, are optimized for each dimensional case to achieve the maximum absorbed power. A comparison of the absorbed power in different dimensional cases suggests appropriate WEC dimensions and the corresponding stiffness and damping coefficient of the PTO system for different application locations.