Feasibility study of twin-rotor Savonius wind turbine incorporated with a wind-lens

Abstract

Sustainability and more power generation are vast crucial issues in the commercialization of vertical axis wind turbines specifically for small-scale and urban applications. Savonius rotors are an attractive kind of turbine compared to other wind turbines due to their simple design and self-starting capability. However, these types of turbines have low performance in terms of power generation. This study employs a wind accelerator called “wind-lens” for Savonius wind turbine in single-rotor and twin-rotor configurations to harness more viable energy even in the low-speed region. The results of the present study can help designers and scientists to interpret the effective parameters of the proposed system for further development. High-fidelity numerical simulations are performed to investigate operational parameters like tip speed ratio and geometric parameters such as the rotational direction and position of the rotors within the wind-lens. Also, using the pressure and velocity contours along with the streamlines, an attempt is made to describe the power improvement by the proposed system. The results show that a twin-rotor ducted turbine in the optimal point can improve the maximum power coefficient of the system by about 114% relative to an open turbine.