Numerical study on enhancing the performance of air turbines in Oscillating Water Column wave energy converters

Abstract

Many studies verify that fossil fuels are the main factor responsible for climate change and other environmental issues. Studies on alternate unconventional power sources have received more serious consideration. The conversion of wave energy is among several essential types of green energy. Among the frequently utilized methods for converting wave energy is the Oscillating Water Column (OWC) device. This study investigates the efficiency optimization of OWC devices by enhancing the performance of air turbines. The study is primarily concerned with the performance of air turbines performing as power take-off in OWC systems. The OWC analytical formulas for output power and overall efficiency are illustrated in this paper. The modelling and operation of a Savonius S-type rotor-based counter-rotating vertical axis wind turbine (CRWT) is investigated in this paper using a computational simulation approach. Using the software ANSYS, modelling and numerical simulation are carried out. Better performance properties can be observed in the counter-rotating model compared to a single-rotor design. The results show that these turbine adjustments contribute to noticeable enhancement in turbine performance, which directly affects the optimization of OWC efficiency. In comparison to a single-rotor wind turbine design (SRWT), the counter-rotating design has improved properties in terms of torque, power, and their corresponding coefficients. The CRWT system generates more than twice the maximum power of an SRWT. At a speed of 9 m/s, the maximum output power of CRWT is 18 W, while the power of the individual bottom rotor at the same speed is limited to 3 W.