Wind turbines design calls for selecting an airfoil which produces maximum lift,
with minimum possible drag [3,4]. This means that the airfoil must ‘fly’ at an angle of
attack consistent with high lift, but not so high that the blade stalls, so that the angle
of attack, and actual wind direction relative to a moving blade should be determined.
Also to get the desired lift, the flow on the airfoil must be remaining non-separated
[1,8]. Also there are many other important factors necessary for consideration in the
designing of wind turbines, such as rotor design (blade surface area, frontal area, and
blade strength), structural design, and control systems, etc