Computational analysis of Savonius wind turbine modifications including novel scooplet-based design attained via smart numerical optimization
The numerical (3D CFD) analysis has shown that simple modifications of the blades can be better than more complicated shapes such as spline or elliptical curve. This has encouraged the investigation on what is the limit to the optimized design which used only simple circular-arc based blades. Thus, we perform a global optimization of Savonius blade pair where each pair is composed of two circular arc segments. The smart numerical optimization was performed using 2D CFD and the results were verified and compared with the previous designs using the 3D CFD. The selected optimization operating conditions were tip speed ratio 0.9 and wind speed 12 m/s. The novel optimized design achieved 39% improvement of the maximum power coefficient relative to the classical Savonius design.