Abstract
This report introduces an attempt for wind turbine using blades with circular cross section, although many wind turbines now has blades with wing section. The blades with circular cross section become profitable with strength, stiffness and manufacturing cost in comparison with wing type blades. They are not pure circular cylinders, but have grooves on their surface in long distance direction. A groove forces boundary layer transition on the flow, and that causes asymmetry flow around circular section. The blade with circular cross section produces lift. We performed some wind tunnel test for the blade with circular cross section. Wind tunnel test shows that maximum lift coefficient is 0.6〜0.8 at Reynolds number 1.509×10^5〜2.515×10^5, and suggests that the wind turbine using blades with circular cross section is low speed high torque type.
