The effect of spacing between inner blades on the performance of the Savonius wind turbine

Savonius wind turbine is an interesting type of vertical axis wind turbines (VAWTs) which has a low cost of manufacturing, however, this turbine has a relatively low power output compared to the other types of VAWTs. Further study is required to enhance its performance to match the high demand of the power generation in small-scale applications. The main objective of the current study is to enhance the power output coefficient (Cp) of the conventional Savonius rotor by adding two-inner blades to the geometry. The performance assessment was performed for five different angles of inner blades (100 degrees, 120 degrees, 140 degrees, 160 degrees, and 180 degrees). Moreover, the effect of spacing between inner blades was numerically examined for three values of spacing i.e. 0.02, 0.01, and 0.005 m. The current two-dimensional simulation was performed utilizing the Ansys Fluent solver. The simulation results affirmed that the maximum enhancement to be 32.9% compared to the conventional rotor at TSR equal to 0.7 when the spacing between inner blades is 0.005 m with an inner blades angle of 100 degrees. Moreover, results demonstrated that the Ct max is 0.435 at TSR = 0.4 for the rotor with 160 degrees inner blades and a spacing of 0.005 m.

Automated summary

The study aimed to enhance the power output coefficient of the traditional Savonius rotor by adding two inner blades, revealing a significant increase in power under specific conditions.