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Old 01-14-2021, 11:34 AM   #38 (permalink)
Vman455
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Pope Pious the Prius - '13 Toyota Prius Two
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Quote:
Originally Posted by aerohead View Post
1) Frontal area-based drag coefficient has been the industry standard basically all along.
2) I don't mention 'aeronautics' just as I never mentioned 'aerodynamics' with respect to static 'lift'. Please read for comprehension and pay close attention to actual language!
3) Any 'profile' will be profoundly affected by fineness-ratio. Any given frontal area demands a matching length to preserve the fineness ratio.
4) For road vehicle aerodynamics, scaling-factor has to do with dynamic similarity, verisimilitude, precisely related to Reynolds number. It's an absolute necessity with respect to scale-model wind tunnel testing.
5) I don't 'conflate.' The science speaks for itself.
6) A 'life-size' automobile, above 20-mph, will be at super-critical Reynolds number, and constant drag coefficient up to transonic velocity.
7) We don't need to concern ourselves with RN effects of a 'real' car.
8) The context of modern 'competition laminar' bodies is exactly related to frontal area, as it undergirds every other dimension of the body architecture.
One cannot understand the 'context' of a 'laminar' body without this understanding.
That was the condition of the discussion.
I'm not even going to bother to respond to the rest of this because I'm not nearly as patient as some of the other posters here, but re: 7) One thing Hucho did write to me was an explicit warning to be careful in testing devices on my car since front and rear spoilers can be sensitive to Re effects.
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