Numerical Investigations on the Performance of Cross-Flow Hydrokinetic Turbine

Lot of potential is available in free-flowing streams, which can be tapped by using a hydrokinetic turbine (HKT) to help achieve net-zero carbon emission in the energy system. Among different types of HKTs investigated by various researchers, a cross-flow turbine is considered as most suitable device to harness the hydrokinetic potential in canal and riverine applications. Thus, the present study aims to numerically investigate various cross-flow turbines such as advanced Savonius, Darrieus and hybrid HKT rotors. In order to compare their performance, rotor of these turbines having the same diameter of 150 mm and number of blades as 3 under constant flow velocity of 1.0 m/s is considered. Based on 2D computational results, it is found that the performance of a hybrid rotor exhibited better performance as 109.15% and 24.78% greater than the Savonius and Darrieus rotors in terms of maximum power coefficient. Further, a hybrid rotor exhibited higher torque coefficients and smooth torque fluctuations than the other two rotors due to the distribution of drag and lift force equally at each azimuth position on turbine blades. The results of this study may be useful for further studies to deploy this technology in the field.