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Old 12-11-2008, 03:30 PM   #23 (permalink)
aerohead
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golfball

Quote:
Originally Posted by Cd View Post
How does dimpling help on a golf ball if the ball is spinning constantly ?

As far as dimples on automobiles, I notice that Lexus did a famous job of dimpling the LS430 underside, and to my surprise VW is still using dimpling on the undersides of their cars . There must be something to it, otherwise they wouldn't bother ( Lexus used the dimples as a PR stunt, and this may have been the actual reasoning behing the dimples, but why then is VW using them if they don't really work ? )
Evidently,the spinning is of little consequence, as the revolving "face" always presents the dimples to the "oncoming" flow.At a clubhead departure velocity of 110-mph,Reynold's Number goes supercritical immediately,and drag coefficient drops from 0.47 to 0.10.----------------------- As mentioned elsewhere,the floor of the Lexus is a sandwich of 2-layers of sheet steel,encapsulating a membrane of acoustic deadener.The presence of the dimples further alters the resonant frequency of the floor,along with any harmonics which might occur within the range of the engine/driveline vibration.
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