Investigation of a helical Savonius turbine with a deflector system

The growing demand for renewable energy sources to meet electricity needs has underscored the importance of exploring new resources of renewable energy. Among the various alternatives, Helical Savonius rotors have emerged as one of the most widely used technologies for small-scale hydropower generation. Numerous studies have been conducted to investigate these types of rotors, particularly to enhance their power output. Despite existing research, there is still a need for modifications and proposals for new configurations of Savonius rotors. This paper presents a numerical study of a Savonius rotor equipped with a new design of a deflector. The results indicate that the highest power coefficient achieved is 0.1247 at a tip-speed ratio of 0.7 in the absence of a deflector system. The geometric parameters of the deflector are varied to identify the configuration that generates the highest power output. With the implementation of an optimal configuration for the new deflector system, the maximum power coefficient is improved to 0.168 at a tip-speed ratio of 0.7. Otherwise, the maximum power coefficient could be enhanced by 34% compared to the same configuration without a deflector. This significant improvement highlights the potential of the proposed design system.