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Old 06-25-2008, 06:36 PM   #21 (permalink)
NeilBlanchard
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Hello,

Quote:
Originally Posted by lunarhighway View Post
yes sure, but that's the catch, total aero drag is frontal area (in square feet or meter) multiplied Cd

this is gives you a CdA

a tiny car with a 0.32 Cd might have less overall drag than a prius, just because the prius has more frontal area...

frontal area determins how much air will have to be pushed around the car, drag quoeficient how smooth this will go
Right, I understand that. My comment was towards what some posts seem to be saying: that just because a vehicle is taller, means that it must necessarily therefore have a higher drag coefficient.

The OP does list an item saying that "...lowering by 20 mm reduces Cd by 0.01" which implies that this is a linear affect. I can't see how this could be a constant? All else being equal, lowering a vehicle only reduces the frontal area of the tires only.

Both the Boxfish and the Aptera are relatively tall, and they have much lower Cd than almost any other vehicle; so height is only one possible factor in the Cd.

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