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Old 10-07-2010, 07:16 PM   #5 (permalink)
aerohead
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Quote:
Originally Posted by Patrick View Post
WRT #12):

Aircraft wing section coefficients are calculated based on the planform area, not the frontal area. So for a 6% section, you have to multiply the coefficent by 16.67 (100/6): 0.003 x 16.67 = 0.05 Cd based on frontal area. So the 0.103 found in the CalTech wind tunnel is only a 106% increase. For comparison, what were the Cds of the other bikes in the competition?

The GM Sunraycer was based on a 63-series wing section and AeroVironment claims that laminar flow was achieved up to the 30% chord maximum thickness.
Thanks Patrick!,I seem to be falling into the very traps I'm trying to keep everyone out of.Yes,a big heaping bowl of stupid can be found being served up at the Knox household!
As to the other bikes,it was presumed that they all shared virtually the same Cd.Not much of an answer I know.
I plan to go back next year,and not on the closing day,so perhaps I can glean more info and query more teams.
I thought Sunraycer's overall flow would be laminar in its entirety.I've seen wind tunnel smoke-flow images of similar cars and there is no perceptible separation the whole length,smoke,quite literally clawing the aft-body surface.Beautiful!
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