Design for a circular arc shaped multi-blade windmill

원호형상의 멀티 블레이드를 가진 풍력터빈 설계

The characteristics of the circular arc shaped multi-blade windmil are investigatedl. The prototypical windmill was tested in the laboratory at wind tunnel speeds of 5.5, 9.4m/s. and the model windmill was also tested in the laboratory, The power and torque coefficients were studied as functions of the blade section, the aspect ratio for blade diameter and windmill radius(M = 0.3, 0.5, 0.7), the number of blades and finally the tip-speed ratio. The analysis of the experimental results for the model windmill showed that there is the highest revolutions per minute(R.P.M) at the circular arc shaped multi-blade windmill having the blade number 10, aspect ratio(M = 0.7). and the results for the prototypical windmill showed that the power coefficient increased to a maximum value and then decreased again with an increase in the tip speed ratio, while the torque coefficient decreased directly with an increase in the tip speed ratio Finally, the experimental results were compared with the Savonius blade. the maximum power coefficient for the arc shaped blade was greater than for the Savonius blade and occured at a lower tip speed ratio.