Abstract
Experiments were conducted to explore the effects of the mutual interaction between two widely spaced Savonius rotors within a wind tunnel. The number of revolution was investigated for two different velocity and conditions, being under small friction and high friction with revolution control. The optimum set of the parameter was found to be u= 4.0 m/s, (x, y) = (2.0D, 0.5D) with two rotors rotating in the same direction under small friction, and the number of revolution of them became 9.1% larger than that of the single rotor. In contrast, increase of revolution was not observed with u= 5.0 m/s under the condition of revolution control and high friction. This result shows that the mutual interference of two Savonius rotors depends on the relation between wake structure and tip speed ratio.