抄録
In recent years, the rotors for small wind turbines designed to have low tip speed ratio are increasing in number because of their reduced noise. The development of generators and controllers suitable for low rotational speed is largely accelerated these years. While there are many papers on the small wind turbine rotors with high tip speed ratio adjusted for conventional generators, a number of the paper systematically dealing the rotor shapes applied for low tip speed ratio is very small. In this study, two types of experimental models are prepared to compare the performance at low tip speed. One has a rotor with tapered blades designed by the combined blade element and momentum theory, and the other has a rotor with inversely tapered blades in which the calculated chord lengths are applied in an opposite way. In this paper, the authors report a result of a performance test in a wind tunnel on experimental models.
