Performance investigation of a Savonius rotor by varying the blade arc angles

Wind energy is a promising source of renewable energy due to its availability. Savonius turbine is a vertical axis wind turbine that converts kinetic energy from the wind to mechanical energy. The current research investigates the performance of the conventional Savonius turbine by varying the position of the endpoints based on varying the blade arc angle. In addition, the outer blade arc angle of a modified configuration, which generated by varying the gap ratio, is also investigated. The ANSYS-Fluent package is used to perform the numerical simulation of the turbine to solve the equations of the unsteady Reynolds Averaged Navier–Stokes (RANS). The flow characteristics through the turbine are resolved by using the SST k-ω turbulence model. The numerical result of the conventional configuration is validated by using previous numerical and experimental research works. The current investigation proved that varying the outer and inner blade arc angles to 160° and 20° enhanced the maximum power coefficient by 4.5% and 12.9%, respectively. Furthermore, the maximum power coefficient of the modified Savonius rotor at a gap ratio of 0.1333 and an outer blade angle of 180° increased by 13.6% compared to the conventional profile.