Influence of Pivoted Blades on the Static Torque Characteristics of Savonius Turbine

Savonius turbine is a Vertical Axis Wind Turbine (VAWT) capable of producing energy from low wind velocities or regions. It produces mechanical energy predominantly by the drag forces acting on the blades. The Savonius turbine overcomes significant disadvantages of Horizontal Axis Wind Turbines (HAWT), but Savonius turbine produces less power compared to HAWT. The primary reason for the lesser power coefficient of the Savonius turbine is that for part of the cycle, the forces acting on the turbine's blades assist the rotation of the turbine (advancing mode). However, for the remaining part of the cycle, the blades have to resist the rotation of the turbine (returning mode). In the present study, an attempt has been made to improve the turbine's performance by pivoting the blade to reduce the resisting force acting on the blade during the returning mode. ANSYS Fluent 2019R3 solver with the SST K-ω turbulence model has been used to numerically study the pivoted Savonius turbine's effect. Improved static torque variations are observed in the Savonius turbine due to pivoting of the blades.