Aerodynamic behaviour of small savonius turbine with 3 different configurations

The primary objective of this paper is to study the effect of different configuration of Savonius type domestic scale vertical axis wind turbine with semicircular shaped blades. A 16-bladed rotor was initially designed and its torques and angular speeds were measured over a range of wind speeds using a wind tunnel. The second prototype was designed in such a way that the blades were slightly twisted with the base plate diameter larger than the top plate diameter to enhance the turbine efficiency by directing the air flow to the tip of the base plate to increase the tip speed. The third prototype was designed with the top plate larger than the base plate to enhance the turbine efficiency by directing the air flow to the tip of the top plate. Maximum power curves as a function of wind speeds were established for each configuration. The results show that the rotor design with inverted-pyramid configuration extracted more energy from the wind compared to the straight configuration by around 27.1 % and pyramid configuration by around 48.9 %.