NASCAR naca duct use

Please discuss here all your remarks and pose your questions about all racing series, except Formula One. Both technical and other questions about GP2, Touring cars, IRL, LMS, ...
MadMatt
MadMatt
125
Joined: 08 Jan 2011, 16:04

NASCAR naca duct use

Post

Sorry for my ignorance but what are the ducts on the rear windows of nascar for? I heard they are to enhance the flow to the rear wing, is that true? How do they do that? (pictures would help too) :)

bhall
bhall
244
Joined: 28 Feb 2006, 21:26

Re: NASCAR naca duct use

Post

How about an article?

Sombrero
Sombrero
126
Joined: 22 Feb 2012, 20:18

Re: NASCAR naca duct use

Post


MadMatt
MadMatt
125
Joined: 08 Jan 2011, 16:04

Re: NASCAR naca duct use

Post

Thanks guys, but my main interrogative point was about the possible routing of the ducts to help the flow at the rear of the car. Is that something they are doing? :)

countersteer
countersteer
9
Joined: 28 Apr 2007, 14:37
Location: Spring Hill, TN

Re: NASCAR naca duct use

Post

I believe the ducts are used to route air to the rear axle cooler and/or the driver's cool suit and/or the driver's air tube (that runs into the helmet). While the primary purpose of the ducts is not purely aerodynamic, I'm willing to bet that there has been some creative use of the downstream air after it serves its purpose.

Greg Locock
Greg Locock
233
Joined: 30 Jun 2012, 00:48

Re: NASCAR naca duct use

Post

The trick with internal air passages is to ideally pick up from a high pressure point (stagnation point) and vent it into a low pressure point. The improvement in Cd can then be used to allow a better wing setting.

This is more effective than using the vented air directly to create downforce, unless you can blow it across a wing.

User avatar
MOWOG
24
Joined: 07 Apr 2013, 15:46
Location: Rhode Island, USA

Re: NASCAR naca duct use

Post

Interesting thread with lots of information. Thanks for the links and input. =D>
Some men go crazy; some men go slow. Some men go just where they want; some men never go.

User avatar
Pierce89
60
Joined: 21 Oct 2009, 18:38

Re: NASCAR naca duct use

Post

Greg Locock wrote:The trick with internal air passages is to ideally pick up from a high pressure point (stagnation point) and vent it into a low pressure point. The improvement in Cd can then be used to allow a better wing setting.

This is more effective than using the vented air directly to create downforce, unless you can blow it across a wing.
They don't use wings anymore. In fact, IIRC, the spoiler is at a mandated angle and not adjustable. JT?
“To be able to actually make something is awfully nice”
Bruce McLaren on building his first McLaren racecars, 1970

“I've got to be careful what I say, but possibly to probably Juan would have had a bigger go”
Sir Frank Williams after the 2003 Canadian GP, where Ralf hesitated to pass brother M. Schumacher