Thread: The DragBean
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Old 12-13-2015, 08:33 AM   #21 (permalink)
Cd
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Quote:
Originally Posted by DragBean View Post
@CD

So why would rounding the front NOT decrease the overall drag? Pretty much in any sub-sonic application a rounded approach will allow air to slip around the object far better than a flat face.

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Air works in crazy ways. This car had a Cd of .19 :
The figure was later brought up to .20-.21 i believe.

This car tested out at .201 ...with the hood scoop :


Source : http://www.hotrod.com/how-to/paint-b...-aerodynamics/

Gm tested the EV-1 at their tunnel that gives a reading lower Cd reading than the example I just gave with the Camaro.
So ...That Camaro has a better drag coefficient than the EV-1.

Oh - and an interesting factoid : The guy that tests the Camaro in that article worked at GM on the aerodynamics of the EV-1.

Boggles the mind doesn't it ?

Rounding the corners does decrease drag, but only a slight amount is needed to retain attached flow.



Other times though, a sharp edge is better. You see a lot of new vehicles with fake scoops at the corners of the front ends. Air forms a pocket there and skips around the wheels of the vehicles creating an " air curtain"

It all makes a person just throw their hands up and say " whatevah ! "


Last edited by Cd; 12-13-2015 at 08:51 AM..
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