Numerical Study on the Effect of Installing Circular Cylinders in Front of the Returning Blade and Beside the Advancing Blade of the Savonius Wind Turbine

Previous research has proven that placing a disruptive cylinder in front of the Savonius wind turbine’s returning blade can significantly increase the performance of the Savonius turbine. In this study, two-dimensional unsteady simulations with a quadratic pave-type structured mesh showed that the circular cylinder placed in front of the returning blade and next to the advancing blade provides the best performance results at a free flow speed of 5 m/s and a Reynolds number of 100,000. In this study, the comparison with experimental data from another study is utilized. The Savonius turbine is installed with an interfering cylinder in front of the returning blade and next to the advancing blade; the air is tighter on the concave side of the advancing blade. The coefficient pressure difference between the convex and concave sides of the blade increases. The maximum moment is achieved in the turbine with a disturbance cylinder at a configuration distance of S/D 1.4 – Y/D 1.61. The maximum moment coefficient is obtained at the position θ = 15°. The placement of two cylinders with a ratio variation of 0.5 D can significantly influence turbine performance. Results show the turbine provides the highest Power Coefficient when TSR = 0.6. The power coefficient increased by 25.11% compared with that of conventional Savonius turbines. Therefore, it can be concluded that the turbine is the optimal configuration for generating the highest power.