Enhancing the aerodynamic performance of a savonius wind turbine with Taguchi method

Savonius wind turbines are a type of vertical axis wind turbines. They catch wind with their blades and produce electricity with electric generators. In this research, effect of some design parameters such as blade type, overlap ratio, separation distance and blade thickness to the aerodynamic performance of a savonius wind turbine was investigated numerically with using realizable k-epsilon turbulence model. 3 Different values were selected for all parameters. Computational fluid dynamics analyses were performed with using Fluent software and Taguchi method was used for the optimization process through Minitab software. It was seen that a savonius rotor with the elliptical blade which has 2 mm thickness, 0,15 overlap ratio and -7,5 mm separation distance shows the best aerodynamic performance. In higher tip speed ratio values, it was observed that the difference between aerodynamic performances of conventional and optimized rotor is greater than in lower tip speed ratios. Power coefficient was raised almost 92,2% for tip speed ratio = 1,4. Optimum tip speed ratio value was changed after the optimization process.