Smooth wheel covers on latest Ferarri F1 race car?
 

I've seen several pics of the vehicle here and there, and it sure looks to me like it's got smooth wheel discs, with holes in the center for the wrench.

http://www.wired.com/images_blogs/au.../ferrarif1.jpg

And they added graphics of a fake alloy spoke pattern to them. Is Ferarri that conservative that they felt that was necessary?

Larger pics;

• Large, front wheel closer up: http://premium.f1-live.com/f1/photos.../diapo_109.jpg

• Here's a link to a lage image: http://www.victorgiardina.com/motof1...per-2009-1.jpg

• And another big one: http://www.victorgiardina.com/motof1...per-2009-2.jpg

They have had them for several years. Most cars in the field have them now. There alr also covers on the rear wheels as well. Their original ones did not have the spoke graphic. Their wheel sponsor, BBS, got a little hacked that no one could see their wheels/logo. A few races later the graphic was there. The covers are attached to the wheel nut somehow.

The covers also have to do with how the brake cooling ducts work. Audi used a weird wheel design on some of their rally cars in the '80's.

Don

It is interesting to note that they do not rotate with the wheels.

Well, there you go. Learned several new things. (Obviously I don't follow F1!)

Interestingly, it was the fake wheel graphics that caught my attention on the Ferarri. They look as odd to me as the fake/distorted Photoshopped alloy wheels you sometimes see in print advertising of new car models (maybe you know what I'm talking about).

Right, and the have openings in the lower/rear part of the cover; for ventilation to help cool the brakes. Some cars have thes on the rear wheels, too -- but those rotate with the wheel:
http://static.guim.co.uk/sys-images/...la-one-001.jpg

Vented too? Cool - I keep learning things! I had no idea.

Ya, they've had those a while. If I recall correctly, the whole wheel cover comes off together with the nut when they change the wheel in the pits... looks kinda goofy, like those things they put around dog's collars to keep them from getting at an injury ("satellite dishes")

The openings line up with the brake calipers in most cases. Prevents the caliper from getting too soft.

Do they attach to the hub? I guess the hub would have to have a non-rotating part that goes through the wheel?

They were developed for brake cooling efficiency, not (primarily) for making the airflow at the outer side of the wheels less turbulent. This does not mean, however, that aero efficiency is not the goal:

They absolutely must keep the brakes cool over a 2-hour race distance with hundreds of multiple G-force braking events, with the carbon discs getting up to about 1500 deg surface temp. If the brakes overheat the race is done. The way they used to ensure adequate cooling was to just increase the brake duct size, which increases drag, but also, more importantly (for racing), contaminates the airflow over vehicle surfaces, esp. the rear wing, which reduces downforce. These wheel covers with strategically placed vents, in conjunction with inner ducting and disc covers, allow the same amount of cooling from smaller brake ducts. The wheel covers certainly must aid the extraction of the brake cooling air in part by reducing turbulence over the tire/wheel face, but the reducing turbulence is not their end purpose. In short, the design is not for making the brakes cooler, but for improving aero efficiency (mainly downforce).

As to how the wheel covers do not rotate with the wheels, you can see the pit men rotate the wheel cover when they first put the wheel on until it locks into place. I've never heard it explained other than by reference to a ball-and-detent mechanism.