Quote:
Originally Posted by aerohead
"Fluid seeks to avoid very large velocities while negotiating sharp edges,and forms surfaces of discontinuity instead." Ludwig Prandtl,phD.,Gottingen Wind Tunnel,Germany.
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Quote:
Originally Posted by Joenavy85
a general rule of thumb: moving alot of air slowly is more efficient than moving a little bit of air quickly. that's the reason why helicopter rotors are as big as they are
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EXACTLY. That's why a shallow windshield and hood, moving air out of the way (upward) more slowly, are more energy efficient. That's why the Prius has a 20° and a hood with almost the same angle, and all those surfaces are smooth and gradually curved.