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Old 06-01-2011, 06:31 PM   #90 (permalink)
aerohead
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turn

Quote:
Originally Posted by orbywan View Post
All I was getting at when I brought up the 'wing' analogy was that when you make the turn from the vehicle side to the surface of the boat tail, it seems to me that it should be curved at that point, similar to the shape of a wing, to keep the air from separating at the turning point.

If the curve involved creates a little lift, which I doubt, I'm betting it's still more efficient than having a tight angled turn in that much surface area.
If the vehicle has completely flat sides,you'd apply the same curvature from the
'Template' as you're using on the roof,as the sides permit.
If the vehicle is taller than it is wide,just use the 'Template' for the width,then copy that curvature for the top.
The 2011 Prius boat-tail trailer illustrates the first condition.
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By using the same curvature,top and bottom,it's a way to help prevent longitudinal vortices which have enormous drag.And it avoids the tight turn you mention which would trigger separation right there.
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