The effect of inner blade position on the performance of the Savonius rotor

• Published in: Sustainable energy technologies and assessments 2019-12, Vol.36, p.100534, Article 100534
• Main Authors: Al-Ghriybah, Mohanad, Zulkafli, Mohd Fadhli, Didane, Djamal Hissein, Mohd, Sofian
• Format: Article
• Language: English
• Subjects: Inner blade; Inner blade position; Savonius; VAWT; Wind energy
• ISSN: 2213-1388
• DOI: 10.1016/j.seta.2019.100534

•The effectiveness of the inner blade on a Savonius VAWT has been proved to work considerably well.•The new configurations were able to enhance the performance of the turbine significantly in terms of power.•The effect of inner blade position on the performance of the Savonius rotor was studying using a CFD approach. In this study, the effect of the inner blade position on the performance of the Savonius rotor has been investigated numerically to determine the best position of the inner blade. Five values of inner blade angles are adopted (180°, 160°, 140°, 120°, and 100°). Two-dimensional simulation is performed for the conventional rotor, rotor with the inner blade tip parallel with rotor tip, and rotor with the inner blade parallel with rotor root keeping the main rotor diameter constant in each case. The simulation has been achieved using the k-ε/realizable turbulence model with the assist of the ANSYS-Fluent solver. The torque coefficient (Ct) and power coefficient (Cp) are estimated as a function of tip speed ratio (TSR) for each case. Finally, the total pressure, velocity, and streamlines are obtained and analyzed. The numerical results demonstrated the maximum Cp to be 0.1885 at TSR equal to 0.5 when the inner blade is placed parallel with rotor tip with inner blade angle of 120°. Moreover, results found that the maximum Ct is 0.407 at TSR = 0.4 for the rotor with 180° inner blade. Furthermore, the peak value of the torque found to be generated at the azimuth position of (θ = 105°).