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Old 09-22-2012, 07:34 PM   #18 (permalink)
freebeard
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Aerohead -- Thanks for you thoughts. Have you posted your Bonneville stories anywhere? I have a post at Project the third that I would appreciate your comments on.

Quote:
...the Morelli form has failed to demonstrate lower drag than a half-body 'pumpkin seed.' ... I believe that if you will exhaust all avenues,you will come to the realization that you're not going to beat the 'Template.'I've been actively looking since 1973.
I'm not looking so much to beat it, as to find some way to accommodate it into my life. Life full of compromise, if you take the half body of revolution and hang a license plate on it, you've already compromised.

Quote:
An example would be the square fuselage of the 'Spirit of St.Louis' with Cd 0.247 and the 'round' fuselage of the Arado 'Smooth' of similar fineness ratio,at Cd 0.06.
Now that right there is what I was looking for. One would expect the superllipse to have Cd ~0.15.


ERTW -- This is how I'm seeing it:
Quote:
Imo as long as the air on the top and side is the same, sharp edges won't hurt. It's when there is a pressure differential that sharp edges will accentuate it and create vortices. In that case a round edge will allow a gradient, and not feed vortices
So we have a preferred shape (or shapes), with the wheels spats and departure angles; we know that surface dirt and duct tape are trivial. That leaves the scale from drip rails and door handles up to rear view mirrors to think about. Maybe air scoops behind the rear view mirror to eat its vortex?
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