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Old 02-08-2012, 10:34 AM   #144 (permalink)
Ken Fry
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Quote:
Originally Posted by sendler View Post
So after all my fretting and thinking my contentions would be soundly trounced, it looks like Vetter has recently chopped off his tail as I would have wanted on my streamliner if I had one.

In this side view of an early version of the Zing, if you imagine a single front motorscooter wheel, you'd have an earlier yet version, which used the same fuselage. My reasoning for truncating the rear was to reduce side area and to keep the center of lateral resistance somewhere near the middle of the bike. This allows the self-correcting for cross winds to continue to work. A long tail tends to pivot the bike about the rear wheel, so that the self correcting we've been discussing goes away or is (worse) reversed. (I didn't get enough hours on the two wheel version to verify if self-correction in crosswinds worked, nor enough to evaluate handling in really strong crosswinds.)

Now that the car is three-wheeled, I've extended the tail to reduce the wake -- the Kamm effect (little or no adverse effect on drag by removing the back end) is not valid if flow is fully attached at the point where you cut the back off. In a three wheeler (or four wheeler) where you steer right to go right (imagine!) then having area aft tends to turn the car into the crosswind, which is stabilizing.
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