Experimental study on effective parameters on vertical axis wind turbine performance

Concerns about the usage of fossil fuels have led to more attention to renewable energies such as wind energy. Utilization of wind turbines in the urban industry is one of the challenging topics in wind energy area. Particularly, due to the limitations of the wind conditions in the urban areas (i.e. low speed wind, high level of variation of wind direction and high turbulence level) and the space limitations within the cities, utilization of vertical axis wind turbines in micro scales have become of interest. The focus of the present study is on these types of turbines and assessing the parameters affecting their aerodynamic performances. Two types of vertical axis wind turbines (Savonius and a straight blade Darrieus) were designed and constructed in micro-scale. The effect of wind speed on the Savonius turbine is experimentally studied. Results show that this turbine performs better at lower wind speeds. The effect of the aspect ratio and the vertical position of the blade struts on the performance of the Darrieus turbine is also experimentally assessed. The results show that the best vertical position for struts is the tip of the blades. It was also experimentally observed that the turbine with aspect ratio one has the best aerodynamic performance.