Group at right(above) constructed a cardboard box, presumably to support a generator. It will be interesting to see how they create a bearing in this arrangement.
Beginnings of a Savonius rotor?- I suggested mounting the axle to the bottom panel.
One group, using a 3-bladed design, was able to get their turbine to spin, by using a straw as a sleeve bearing.
They also tried using Lego gears to gear up a small propeller. It would not turn. When the gears were reversed, so that it geared down( 8:40), it spun, but only turned the output shaft slowly. It was suggested that a larger rotor was required, as power is proportional to the area swept by the rotor:
Another group made a flat rotor. This did not turn, as the rotor blades were perpendicular to the wind direction.
Another group used cup-shaped rotors, reasoning that they would catch more wind than a flat rotor( based perhaps on an anemometer). This also did not work, as the angles were not consistent and the cup shaped did not provide thrust in a uniform direction. They also constructed a PVC stand for theit rotor.
Another group made a miniature pinwheel as an art project. However, the rotor blades were not fixed in position, and so it did not turn as of yet.
They also made a little seat for their project:
There seems to be some conceptual confusion between a waterwheel, which is typically powered by a highly directed stream in the same direction of rotation,
and a wind turbine, which is powered uniformly applied moving air at 90 degrees to the axis of rotation.
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