Random Wind Tunnel and Smoke Pictures Thread

[CFECO]

Probably not when the feathers opened like a parachute!

[aerohead]

Originally Posted by California98Civic

Wow this first one is cool... and I like this image too, on the same site:



Amazing the difference made by the modest change between the first on the left and the next one to the right.

And I don't believe Mercedes on this claim:

I suspect that they're context of: compact 'luxury car',and 'production car' qualifies the claim,considering other automakers.

[Cd]

This is a link to a wind tunnel video that is actually USEFUL, versus just the usual puff of smoke over the hood and windshield. Lucky for us, the A2 aero guy was in the tunnel at the time to show the other fella where the important areas were on the car.
There is a '71 SuperBird video I posted earlier much like this one, but this one is so much better.

Note how that the reverse hood scoops mounted on the fenders are functional at extracting high pressure air from the wheel well at 5:46 in the video.

Also, note how that the air is a mess around the front tires and rear window. It is interesting to see where the boundary is in the turbulent air back there.
You can also see the low pressure area as the guy sticks the wand in the cowl just behind the hood.

http://www.youtube.com/watch?v=zl7jk85D2sE

[California98Civic]

Originally Posted by Cd

Note how that the reverse hood scoops mounted on the fenders are functional at extracting high pressure air from the wheel well at 5:46 in the video.

Those scoops are cool. But aren't they actually moving high pressure air from the scoop to the wheel well, not the other way around? At 6:05-6:21 you can see the smoke go into the scoop and come out the wheel well.

[freebeard]

Thanks. Lesson: still pictures don't cut it.

He put the smoke wand right behind and in front of the fender scoop, but I wish he'd filled the wheelwell from below to confirm that it's emptying it.

California98Civic -- I'm a slow typist.

Edit: There goes my spare time for a while

http://http://www.youtube.com/user/A...?feature=watch

57 videos in total. "VW Bug in a wind tunnel?" Shows the Beetle frontwards and backwards and let's you vote to win an A2 T-shirt. But you have to touch facespook to vote. Bummer.

[CFECO]

I cannot get to the U-Tube Vids...thats a real bummer.

[California98Civic]

Originally Posted by CFECO

I cannot get to the U-Tube Vids...thats a real bummer.

Try this link: http://www.youtube.com/user/A2WindTunnel As was noted a couple posts back, some of the A2 vids have been posted before.

[aerohead]

That is perhaps the most thoughtful use of the smoke wand I've ever seen.All the warts and moles are shown.Great stuff! Thanks bigtime!

[NeilBlanchard]

It is a "useful" video, but one wonders about the narrowness of the wind tunnel? I thought the proportions of the tunnel had to be significantly larger than the car to be "true"?

[Cd]

Originally Posted by aerohead

That is perhaps the most thoughtful use of the smoke wand I've ever seen.All the warts and moles are shown.Great stuff! Thanks bigtime!

I wish they would have shown more around the wheels and the underside, since this was the worst area on this car.

I emailed the guy that built this car. No Cd figures were given in the video, so I asked him if he would provide that data for us ( I also asked if he had data on the stock ( as in unmodified ) 'stock' car in regards to its' Cd and lift figures.

The site hasn't been updated in a few years so we shall see if we get a response.

Cali98Civic : I'm parroting what I have read regarding those scoops. Supposedly, those scoops were a last minute solution when the tires began rubbing the fenders above 200 mph. The engineers had some scoops from a SuperBee and attached them to the tops of the fenders backwards to hide a large hole that they added above the wheel "to exit some of the trapped air in the wheelwell." The front end of the car was so planted to the ground at speed that it was reducing the clearance between the tires and the fender.

Why the scoops face backwards is a guess to me. I had read it was to relieve the high pressure air in the wheelwell . It could just be a last minute solution to covering an ugly hole in the fenders, but from what i have read, they had some aero function.

EDIT : I emailed the guy with the car and he has replied that the testing was only done for stability and that no data was given such as Cd or lift.
( How does one pay $ 2,000 an hour and not get info like this ? ) :-/