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Old 09-16-2010, 11:29 PM   #18 (permalink)
RobertSmalls
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Join Date: Aug 2008
Location: Buffalo, NY, USA
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Prius C - '12 Toyota Prius C
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I found this gem in the comments over at the Edison2 blog. Coastdown data were published, but they fit the curve F=A+Bx+Cx²...
Quote:
So that CoastDown data has this A, B, C format which is great but does not match the simplified model of a car that has no B term. So I resampled the data to and refit it to F = A1 + C1 v^2 type of curve fit. The fit is not as good, but it allows calculations of a few key items.

Crr = 0.012
CdA = 0.244 m^2
CD = 0.143 (assuming 1.702 m^2 area)

The numbers seem pretty reasonable and most impressive.
John C. Briggs
Does anyone else think that CRR number is unimpressive?
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