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aerohead · 10-24-2009, 05:53 PM

I'm glad they did the test but I would take them to task for it.The only reason dimples are on golfballs is to hasten the transition to turbulent boundary layer an it's attendant lower Cd (profile drag/pressure drag).
Automobiles,given their size, transition to turbulent boundary layer and constant Cd around 20-mph,so it's not an issue for cars.And the "roughness" of "smooth" paint is all that's necessary for the transition.
I get a kick out of the show but sometimes I wonder if those folks ever pick up books and look at them.

10-24-2009, 05:53 PM	#21 (permalink)
aerohead Master EcoModder Join Date: Jan 2008 Location: Sanger,Texas,U.S.A. Posts: 16,267 Thanks: 24,392 Thanked 7,360 Times in 4,760 Posts	dimples I'm glad they did the test but I would take them to task for it.The only reason dimples are on golfballs is to hasten the transition to turbulent boundary layer an it's attendant lower Cd (profile drag/pressure drag). Automobiles,given their size, transition to turbulent boundary layer and constant Cd around 20-mph,so it's not an issue for cars.And the "roughness" of "smooth" paint is all that's necessary for the transition. I get a kick out of the show but sometimes I wonder if those folks ever pick up books and look at them.