Performance analysis of Savonius rotors with straight and Bach-type twisted blades |
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Velásquez L(1), Chica E(1), Rubio-Clemente A(1,2) 1. Grupo de Investigación Energía Alternativa, Facultad de Ingeniería, Universidad de Antioquia UdeA, Medellín, Colombia.
2026-06-27 |
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Abstract
In this work, experimental comparisons are conducted when two Savonius-type vertical-axis wind turbine rotors of different blade twist angles (γ) are placed with the same aspect ratio (AR = 2.0). During the initial setup, a straight blade (γ=0°) was used in the first design; while in the second configuration, twisted blades were employed with a γ of 30°. The rotors were checked for aerodynamic performance in comparable wind tunnel configurations along with the power coefficient (Cp), the starting torque and the rotational stability. The rotor at a blade γ value of 30° reached a Cp equal to 0.232 compared to the straight-blade rotor (Cp = 0.165). The torque variation with less variability and self-starting ability was observed in the twisted blade setup, which was attributable to a better flow interface of the advancing and return blades. Results demonstrated that a moderate blade twist for the system can improve the aerodynamic efficiency of the Savonius rotors without a significant modification of the production complexity. Thus, the configuration conformed by a γ and an AR of 30° and 2.0, respectively, presented an optimal blend between performance and simplicity, which made it suitable for small-scale power generation under low-wind conditions.
Key words: Wind turbine, Savonius rotor, blade twist angle, aspect ratio, experimental study, aerodynamic performance.
Published in: Renewable Energies, Environment
& Power Quality Journal (REE&PQJ) |
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| ISSUE: Vol. 26. No.1 | Pages: 66-70 |
| E-ISSN: 3020-531 X | Date of Current Version: 2026-06-27 |
| REF: 227-26 | Issue Date: 2026-07-15 |
| DOI:10.24084/reepqj26-227 | Publisher: AEDERMACP/ EA4EPQ |
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