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Old 04-10-2008, 12:10 AM   #27 (permalink)
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I checked out your build thread for the HPV fairing (very cool project, BTW) and noticed that you claimed a Reynolds number of 184. Not 184,000 but 184. Unless I'm totally misunderstanding what you're reporting, that really doesn't seem reasonable--using a characteristic length of 60" and a speed of 30 mph in 20C air I get a Re of 1.4E6. Just to make sure, I did a little looking around the net and even the Re for a bicycle helmet is 1e5.

What am I missing? I ask, because if the Re is really out of line with cars, then your ride height experiment might not be transferable to a car.

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