Thread: CdA list
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Old 04-26-2008, 04:19 PM   #20 (permalink)
aerohead
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frontal area

Quote:
Originally Posted by tasdrouille View Post
One thing I noted though. In every single case where the frontal area was stated, the 0.81 correction factor on h * w you used gived an overly optimistic figure.

I recall reading a post by phil, must have been of of his aero seminars I'll have to search a bit, where he said to use 0.87 or 0.85, can't remember exactly.

Edit: it was from Aerodynamics Seminar # 6 - by Phil Knox
.84 was from "ancient" text,and Hucho's more current 0.81 multiplier reflects the industry use of more tumblehome in modern rooflines.I've glanced at a few semi-current CAR and DRIVER mags and they're reporting some "official" frontal areas that work out in the ninety-percent region,further confounding the likes of aero-modders in search of accutate quanta.Rats! I used to be more current,had subscriptions and everything.I got turned-off by all the paid advertising and let all my subscriptions lapse.Sorry!
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