Performance enhancement of Savonius wind turbine through partially deformable blades

Abstract

In this study, we employ partially deformable blades to elevate the performance of Savonius wind turbines. The Bucket is constructed with rigid components equipped with a guidance system, resulting in continuous changes in its shape during turbine rotation. As the trailing edge of the advancing blade expands, it creates an active slot, effectively correcting the Bucket’s pressure distribution and enhancing the positive torque generated by the turbine. We employ a two-dimensional (2D) numerical model, implemented using the commercial software ANSYS-Fluent 23.0, with the governing motion equation executed through a user-defined function (UDF). This investigation explores the mechanism of performance enhancement by varying expansion amplitudes Our results, obtained at a Tip-speed ratio (TSR) of 1, reveal that when the amplitude of deformation exceeds one-quarter of the Bucket radius, the partially deformable blade outperforms the rigid blade, leading to a remarkable 32% improvement in the torque coefficient. These findings signify a promising path toward enhancing Savonius turbine efficiency.