The cup-shaped rotors on the vertical-axis turbine of the previous chapter are a simple design to capture wind. The cups are pushed around in a circle by the wind. A much more effective way to catch the wind is to take advantage of aerodynamic principles, resulting in a capability for much higher rotation speed. The key aerodynamic principle to consider is the airfoil.
The Airfoil
An airfoil is diagrammed in Figure 4-1; it is a blade shape that uses wind flow to push a turbine blade. Airfoils work by Bernoulli’s Principle, which states ...
