Some construction details and video footage of an unloaded Sharp style VAWT in modest wind conditions. The Sharp VAWT is based on a patent by Peter Allen Sharp. The wing is allowed to pivot at a point approximately 1/4 chord inward from the leading edge of the wing. Wing rotation is confined to about +/- 45 degrees. Counter weights are added to locate the center of mass near the leading edge of the wing. With this arrangement, the apparent wind causes the wing to weathervane while the centrifugal force of the mass pushes the wing into a favorable angle of attack to produce lift and torque on the shaft. While the turbine works well with two wings, this example has four to cut down on force and torque pulsation. Note: the wing mass of 1.50 kg includes the counter weight. The mass per square meter of wing area (wing loading) works out to be 5.2 kg/m^2. In my opinion, it would be better to have a wing loading of around 2.2 to 3.0 kg/m^2. Also, the wing chord is 180mm not 180m.
6 сен 2024
