116 Optimization of wing shape of four wing type vertical axis windmill for wind power generation

The present study investigate the effect of flap angle of airfoil and wing attack angle to obtain the amount of power generation. We also examine the minimum starting wind velocity of the windmill. Flap wing generate electricity efficiently by using the high wing attack angle. And using high flap angle make it possible to obtain minimum starting velocity. To obtain high output power, it is better to keep flap angle of 0° and using high wing attack angle we have obtain maximum output power with wing attack angle of a =29.9° 〜-37.1° .