Go Back   EcoModder Forum > EcoModding > Aerodynamics
Register Now
 Register Now

Now available from EcoModder: ScanGauge II fuel economy gauge.  Click for details.  

Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 11-12-2011, 01:42 PM   #51 (permalink)
The PRC.
 
Arragonis's Avatar
 
Join Date: Oct 2009
Location: Wanting to be in a Mini again.
Posts: 4,891

Hermann - '06 Audi A6 Avant S-Line Quattro
90 day: 31.21 mpg (US)
Thanks: 242
Thanked 413 Times in 300 Posts
Do air tabs work?

__________________
  Reply With Quote
Old 11-15-2011, 02:58 PM   #52 (permalink)
EcoModding Apprentice
 
Join Date: Mar 2010
Location: Los Angeles
Posts: 110
Thanks: 0
Thanked 5 Times in 5 Posts
if anyone has any airtabs laying around to sell, i might buy some. i have a 87 Toyota truck and i drive 352 miles nonstop on the highway.i do this trip 2 times a week.have been for a month and a half.thhis would be a very good test opportunity!!!
  Reply With Quote
Old 05-15-2012, 12:39 PM   #53 (permalink)
MBZ and MOPARS
 
Join Date: Apr 2012
Location: City of Trees
Posts: 11
Thanks: 0
Thanked 0 Times in 0 Posts
Revived again!! I am a nubee, so never got in on all the previous posts regarding VG's. I've messed with Airtabs, specifically, for quite some time now, first on my Dodge Magnum and now on my Jeep GC. The one thing I can say for certain is that they keep the rear windows much cleaner than before when on the highway, and [U]maybe[U] help higher speed stability ever so slightly. I can't say that they make any noticeable difference in FE though. I'd like to think that they do. I've also placed them on the belly pans under the vehicles and in front of some of the suspension components, in an effort to direct airflow away from them. Can't say that it makes any measureable difference either. As said several times, the only real way to verify would probably be wind tunnel tests, as there are too many variables and probably too small a gain to be measured any other way.

A few of us over on one of the LX (Chrysler Products) forums inquired about having smaller ones made, but nothing ever came of it. I too believe that the standard ones are way too big for the smaller vehicles. IMO, they're even marginal for a big sedan/wagon or SUV. They do, however, generate a lot of curiosity and questions from folks that don't know what they are. Keep on tinkering!
  Reply With Quote
Old 01-02-2013, 09:17 PM   #54 (permalink)
EcoModding Lurker
 
Join Date: Oct 2012
Location: muskoka
Posts: 80

Speedy Gonzales - '11 Ford Fiesta SES
Thanks: 7
Thanked 10 Times in 6 Posts
Another revival...
I just want to point out, I build aircraft for a living, and our planes employ VG's on the upper leading edge of the wings.
These are installed in pairs, like a V shape pointed at the wind.
And it is critical, the Angle that they are placed, from one another and to the direction of flow, the spacing between each pair, and the spacing between each other....

The install pics I seen of the small plastic VG's look like they wouldn't accomplish much of anything...

I'll try to upload a pic of ours on the wing....

And I think I might buy some from work and experiment on my cars...
__________________

  Reply With Quote
Old 01-11-2013, 01:37 AM   #55 (permalink)
Master EcoModder
 
Join Date: Feb 2012
Location: Australia
Posts: 344

The Truck - '02 Nissan GU Patrol ST
Thanks: 5
Thanked 48 Times in 33 Posts
My understanding of VG's is they are used to, as mentioned earlier I think, to create controlled turbulance which achieves a thicker boundary layer that promotes clear seperation before the bend where the air would normally wrap around the vehicle creating major vortexes & negative pressure zones, in doing this they are supposed to simulate the effect of a short kamback/boattail which produces a smaller wake area that is set back from the vehicle itself. Like on the Mitsu, by disturbing the air at a higher point before the rear window they effectively soften the angle and allow flow to remain relatively attached, albeit with a thicker boundary layer to the wing on the trunk. So theoretically they can be used to maintain attached flow on angles that are just a little too steep or reduce drag on squared off vehicles, when used on the underside the idea is to use this thicker boundary layer to simulate a belly pan.
From what I have read they do work, but it requires a lot of testing on a specific vehicle to get the right placement and spacing, hence the ratio of failure to sucess is 10:1 or more.
I imagine a simple 2-4" plastic strip taped flush to the body (like mini boattail) following the template lines would achieve greater success as it would promote clear seperation, reduce wake size and push wake further away without the increased frontal area and the ugly factor wouldn't be any worse.
  Reply With Quote
Old 01-11-2013, 10:35 AM   #56 (permalink)
Master EcoModder
 
justme1969's Avatar
 
Join Date: Dec 2012
Location: ff
Posts: 459
Thanks: 59
Thanked 35 Times in 29 Posts
create controlled turbulance which achieves a thicker boundary layer that promotes clear seperation before the bend where the air would normally wrap around the vehicle creating major vortexes & negative pressure zones...

Yes also raises air pressure just at beginning of a low pressure zone so as to reduce compression of a following load face.
It is infacto a small spoiler in itself, like before windscreen if the rake is not correct.
Air transition around object with as little disruption as possible.
  Reply With Quote
Old 01-11-2013, 02:16 PM   #57 (permalink)
Master EcoModder
 
AeroModder's Avatar
 
Join Date: Jan 2010
Location: Oregon
Posts: 471

Tank - '96 Ford Aspire 4 door
Team Ford
90 day: 46.75 mpg (US)
Thanks: 15
Thanked 63 Times in 47 Posts
I have some Airtabs I bought a while back that are just sitting there if anyone wants to give them a try. You'll need to use your own adhesive with them, though.
__________________
In Reason we Trust
  Reply With Quote
Old 01-11-2013, 06:18 PM   #58 (permalink)
Master EcoModder
 
Join Date: Feb 2012
Location: Australia
Posts: 344

The Truck - '02 Nissan GU Patrol ST
Thanks: 5
Thanked 48 Times in 33 Posts
Quote:
Originally Posted by justme1969 View Post
Yes also raises air pressure just at beginning of a low pressure zone so as to reduce compression of a following load face.
It is infacto a small spoiler in itself, like before windscreen if the rake is not correct.
Air transition around object with as little disruption as possible.
So that begs the question if it simulates a small spoiler, why not just have a small spoiler.

I can see that they may be beneficial in specific circumstances, bu the fact that they create drag to hopefully reduce drag makes it very hard to get setup right.
A bit like the bulb infront of large ships, it works fantastic at a specific speed because the wavelength lines up and they reduce drag, but at any other speed the drag is increased.
  Reply With Quote
Old 01-11-2013, 06:21 PM   #59 (permalink)
Master EcoModder
 
Join Date: Feb 2012
Location: Australia
Posts: 344

The Truck - '02 Nissan GU Patrol ST
Thanks: 5
Thanked 48 Times in 33 Posts
Quote:
Originally Posted by AeroModder View Post
I have some Airtabs I bought a while back that are just sitting there if anyone wants to give them a try. You'll need to use your own adhesive with them, though.
Is that a generous offer or a vote of "no confidance"?
  Reply With Quote
Old 01-13-2013, 01:31 AM   #60 (permalink)
Master EcoModder
 
AeroModder's Avatar
 
Join Date: Jan 2010
Location: Oregon
Posts: 471

Tank - '96 Ford Aspire 4 door
Team Ford
90 day: 46.75 mpg (US)
Thanks: 15
Thanked 63 Times in 47 Posts
They don't work for my application, and if someone else could make use of them, all the better!

__________________
In Reason we Trust
  Reply With Quote
Reply  Post New Thread

Tags
fins, generator, vortex

Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Another Vortex Generator Application? jerm1978 Aerodynamics 14 02-19-2009 07:52 PM
Honda's OEM vortex generators ... on the Ridgeline pickup mirrors MetroMPG Aerodynamics 21 12-06-2008 01:09 PM
If your car died, what would you buy? rjacob EcoModding Central 56 08-02-2008 01:42 PM
Is guaranteed 3$/gallon gas worth enough to buy a Chrysler? SVOboy General Efficiency Discussion 29 07-25-2008 06:54 PM




Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com