Wind Tunnel Test
Race Director
Joined: Feb 2005
Posts: 16,100
Likes: 17
I did a "yarn tuft" test on my 69 several months ago...you can see yarn thru rear window blowing towards window...55 mph....
Cowl induction...85 mph...yarn actually sucks in at much lower speed...30 mph...
This is my Bubba wind tunnel...
...(I used fan to determine where to tape yarn for road tests..)
Rich
Cowl induction...85 mph...yarn actually sucks in at much lower speed...30 mph...
This is my Bubba wind tunnel...
...(I used fan to determine where to tape yarn for road tests..)Rich
Last edited by rihwoods; Mar 17, 2008 at 08:35 PM.
Burning Brakes
Joined: May 2007
Posts: 945
Likes: 0
From: Ventura California
The sharp dropoff at the rear window is a major source of drag. As the yarn test shows, the air turbulates as it leaves the rear edge of the roof line. Pretty nice laminar flow up to that point though. I'd be curious to know how much lift is generated by the accelerated flow over the hood. I always figured that dropoff to the rear window would be pretty "dirty" from an aerodynamic standpoint but it is super cool to see it actually tested. Thanks to both posters that included pics of their observations.
Melting Slicks
Joined: Jan 2004
Posts: 3,247
Likes: 210
From: Detroit MI
What was interesting to see was the dirty air that was formed behind the rear glass of the C3. During the smoke test the smoke came over the hood and the top of the car cleanly (as you can see in the picture) but when it hit the open deck in the back it swirled around and filled up the area behind the rear window.
Thread Starter
Race Director
Joined: Jan 2001
Posts: 16,221
Likes: 118
From: Matthews NC
Sorry, I was out of town on business and just getting back on the forum. Unfortunately I do not have any pictures showing the back of the car. The pictures shown were taken by their photographer and they are on the wind tunnel website which I copied over to the forum. Hopefully when the article comes out in the magazine it will show the back of the car too. I'm not sure when it's coming out or how many pictures will be shown.
Thread Starter
Race Director
Joined: Jan 2001
Posts: 16,221
Likes: 118
From: Matthews NC
Thread Starter
Race Director
Joined: Jan 2001
Posts: 16,221
Likes: 118
From: Matthews NC
What do they use to generate the smoke? I think most of us could create a wind tunnel of sorts with a stack of fans and try it ourselves. Not so accurate, but enough to get our jollies.
Or even to do on a scale model set up.
But it is that dense white smoke that makes it work visually. How do that make that?
Or even to do on a scale model set up.
But it is that dense white smoke that makes it work visually. How do that make that?
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
