CONCLUSIONS
In this study, the effect of blade pitch angle on the aerodynamic
characteristics of the HAWT was investigated via CFD simulations, and
the conclusions can be summarized as follows
- Numerical investigation of S809 airfoil shows that the aerodynamic
coefficients from the present model provide reasonable agreement with
the results from benchmark data
- There is the highest positive pressure when the blade pitch angle is
-100 and velocity is 25.1 m/s, and the lowest
positive pressure when the blade pitch angle is 400and velocity is 20 m/s. however, When the blade pitch angle is
300 and velocity is 13 m/s, the blade exhibits the
highest negative pressure and when the blade pitch angle is
100 and velocity is 5 m/s blade possess lowest
negative pressure.
- The torque acting on the blade is maximum when the pitch angle is
-100 and minimum when the blade pitch angle is
400. However, in both the case the wind velocity is
25.1 m/s.
- When the velocity of the flow is 5m/s and 7 m/s, the effect of pitch
angles over predicted the limit of power coefficient which is not
possible in a real application, however, when the wind velocity
changes to 10 m/s, 13 m/s,15 m/s and 15.1 m/s, the results of power
coefficient approaches closer to the real value (0.3-0.4). However,
when velocity increases to 20 m/s, 25 m/s and 25.1 m/s, the results of
power coefficients are below par the real value. The conclusion can be
derived from the above that, In addition to the effect of pitch angle,
velocity is also playing a vital role in determining the effective
power coefficient.