It is also observed that For B=5, the highest value of power coefficient was obtained 0.46, at operating pitch angle-3
degree, corresponding to tip speed ratio-4 while minimum value of power coefficient was obtained 0.05 & 0.02.
At operating pitch angle--3 degree and-5 degree respectively:
corresponding to tip speed ratio-8. Therefore maximum power coefficient is obtained at optimum pitch angle equal to 3
degree, for blade number 3 and 5 respectively-If design tip speed ratio is 8 then the power coefficient decreases by 12% as compared to design tip speed ratio equal to 4 for blade pitch angle equal to 3 degree. Hence proper selection of blade pitch angle can improve machine performance.
Figure 4.6 shows the variation of rotor performance with different initial pitch settings for B=7.
It is noticed that from figure 12, the maximum power coefficient was obtained for operating pitch angle equal to 5 degree and the maximum power coefficient obtained is 0.5 which corresponds 1o tip speed ratio-4 to 5.