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Old 04-13-2011, 06:47 PM   #112 (permalink)
aerohead
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shallow

Quote:
Originally Posted by winkosmosis View Post
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.
"On the drag problem of a body,it might be mentioned finally that the shape of a body in front of the largest cross-section has only minor influence on the total drag.The main contributions to the drag force originate from the rear part of the body.It is not important to find a proper shape to divide the oncoming flow but it is very important to design a rear body surface which brings the divided streamlines smoothly together.Optimum shapes are 'streamlined' bodies having a very slender rear part."
Wolf Heinrich Hucho,ph.D. Mechanical Engineering,Aerodynamics Department,Volkswagen AG,aerodynamic consultant.
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