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Old 04-17-2010, 02:15 PM   #5 (permalink)
aerohead
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Quote:
Originally Posted by jimepting View Post
So,if I interpret this correctly, the best one can hope far in about 3.95% worse than the ideal template, with a boattail that is probably impossible long and low. RobertSmall's proposal looks to be about a 30-40% chop, if one degrades it a bit for the upward slop of the bottom, so he is looking at something like 20 % drag increase from the perfect template. The stock Insight looks to be something like a 70-80% drag increase from the template. Am I in the ball park?
I ran the profile out with some minimum constants for cooling system drag ( 0.011 ),'features drag'( gaps,cut lines,door handles,antenna,wheel openings,etc.) ( 0.007 ),and then subtracted out 0.015 for a complete wheel fairing set using data from the Sunraycer.
It appears that if we do everything 'right',we could get a car down to a conservative Cd 0.126,at 80 % of the template length.
The last bit of drag would be insignificant,residing within the 'phantom' tail.
Running the tail out to 100 % would only get the Cd down to 0.123.
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