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

Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 04-09-2010, 12:07 AM   #41 (permalink)
EcoModding Apprentice
 
Join Date: Jul 2008
Location: Florida
Posts: 135

1991 RED Metro 1.0 Auto - '91 Geo Metro Lsi Auto
Team Metro
90 day: 38.28 mpg (US)

1991 3/5 2 door Blue/green - '91 Geo Metro
Last 3: 42.6 mpg (US)
Thanks: 54
Thanked 16 Times in 14 Posts
No, but due to the interrelatedness of aerodynamics my car might not be doing the same things "normal" cars do. I have about 50% grill block, fairly smooth wheel covers, rear wheel skirts and a Kammback extension.

Just not having the mirrors there is likely changing the airflow dramatically all by itself.

I was looking tonight and the tufts (I'll take some pics tomorrow) blow from about 45 degrees to almost straight up with the window closed, roll the window down about 2 inches and they go mostly horizontal. Strange stuff...

  Reply With Quote
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 04-09-2010, 01:09 AM   #42 (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 65 Times in 48 Posts
I've noticed rainwater being pushed up on the side windows, even close to the top, so that would also confirm the upward flow there. Possibly the result of vorticies induced by spillover from the windshield?

I'm curious to see if adding rails would smooth that out. I'll probably tape some on and do some tuft testing some weekend, provided the weather dries up...
__________________
In Reason we Trust
  Reply With Quote
Old 04-09-2010, 09:46 AM   #43 (permalink)
Master EcoModder
 
NeilBlanchard's Avatar
 
Join Date: May 2008
Location: Maynard, MA Eaarth
Posts: 7,724

Mica Blue - '05 Scion xA RS 2.0
Team Toyota
90 day: 42.48 mpg (US)

Forest - '15 Nissan Leaf S
Team Nissan
90 day: 156.46 mpg (US)

Number 7 - '15 VW e-Golf SEL
TEAM VW AUDI Group
90 day: 155.81 mpg (US)
Thanks: 3,181
Thanked 2,755 Times in 1,720 Posts
The "sharpness" of the 'A' pillars is the key thing, I think that causes the lifting vortexes. This makes me want to do some localized tuft testing...I have the fairings on my video mirrors slightly *downward* because I was thinking that was the way the air moves.

This may be why a lot of newer cars have the mirrors are located farther back from thebase of the 'A' pillars? The picture posted earlier in this thread (or maybe it was another thread) of the fully faired mirrors, may be unusual for a reason.
__________________
Sincerely, Neil

http://neilblanchard.blogspot.com/
  Reply With Quote
Old 04-11-2010, 04:19 AM   #44 (permalink)
EcoModding Apprentice
 
Join Date: Jul 2008
Location: Florida
Posts: 135

1991 RED Metro 1.0 Auto - '91 Geo Metro Lsi Auto
Team Metro
90 day: 38.28 mpg (US)

1991 3/5 2 door Blue/green - '91 Geo Metro
Last 3: 42.6 mpg (US)
Thanks: 54
Thanked 16 Times in 14 Posts
Neil I think you're right, I've seen the illustrations showing the vortexes.I think when I roll the window down some it creates a low pressure area in the cabin and kills the vortex.

Here's a link showing the tufts I have on my car now.
Tuft testing - Picture
  Reply With Quote
Old 04-11-2010, 02:44 PM   #45 (permalink)
EcoModding Apprentice
 
Join Date: Jan 2008
Location: Chicagoland
Posts: 204

- - '10 Toyota Prius III w/Navi
Thanks: 4
Thanked 11 Times in 11 Posts
Hi All,

Upper third A pilar turbulators should lay those tufts flat (in windless conditions). They kill the vortex from forming. Especially on cars with traditional wind shield rakes.
  Reply With Quote
Old 04-11-2010, 02:49 PM   #46 (permalink)
Master EcoModder
 
NeilBlanchard's Avatar
 
Join Date: May 2008
Location: Maynard, MA Eaarth
Posts: 7,724

Mica Blue - '05 Scion xA RS 2.0
Team Toyota
90 day: 42.48 mpg (US)

Forest - '15 Nissan Leaf S
Team Nissan
90 day: 156.46 mpg (US)

Number 7 - '15 VW e-Golf SEL
TEAM VW AUDI Group
90 day: 155.81 mpg (US)
Thanks: 3,181
Thanked 2,755 Times in 1,720 Posts
Right -- I'm using homemade zigzag tape (using Gorilla tape and pinking shears) and I'll have to try some tuft testing now...
__________________
Sincerely, Neil

http://neilblanchard.blogspot.com/
  Reply With Quote
Old 04-13-2010, 04:31 AM   #47 (permalink)
EcoModding Apprentice
 
Join Date: Mar 2009
Location: Oregon
Posts: 175
Thanks: 0
Thanked 63 Times in 41 Posts
Maybe not what you want but....

I think the most areo dynamic mirrors are actually from a motorcycle the Suzuki Hyabusa. my 1 cent
  Reply With Quote
Old 04-13-2010, 11:29 AM   #48 (permalink)
Pokémoderator
 
cfg83's Avatar
 
Join Date: Dec 2007
Location: Southern California
Posts: 5,864

1999 Saturn SW2 - '99 Saturn SW2 Wagon
Team Saturn
90 day: 40.49 mpg (US)
Thanks: 439
Thanked 527 Times in 354 Posts
DIMS -



Yeah, they look nice. Almost "side-vertical" installation angle for mounting. I think I've seen these installed on a tuner-car.

And here's an aftermarket one with thinner stalk :



CarloSW2
__________________

What's your EPA MPG? Go Here and find out!
American Solar Energy Society

Last edited by cfg83; 04-13-2010 at 11:36 AM..
  Reply With Quote
Old 04-13-2010, 01:24 PM   #49 (permalink)
Master EcoModder
 
Join Date: Oct 2008
Location: Mid-Atlantic
Posts: 491

OurInsight - '06 Honda Insight
Thanks: 170
Thanked 68 Times in 43 Posts
Carlos, could you put in the link to the aftermarket mirror? I'd like to take a look. Your picture doesn't come through to me.
  Reply With Quote
Old 04-13-2010, 02:35 PM   #50 (permalink)
Master EcoModder
 
3-Wheeler's Avatar
 
Join Date: Dec 2008
Location: Southern WI
Posts: 824

AlienMobile - '00 Honda Insight
Team Honda
90 day: 80.05 mpg (US)
Thanks: 94
Thanked 549 Times in 189 Posts
Look here for more details on what a good mirror shape could look like:

http://ecomodder.com/forum/showthrea...pes-11183.html

Figure 12 on this page gives a good idea for a more ideal shape.

Jim.

  Reply With Quote
Reply  Post New Thread


Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Side mirror drag & effect on fuel economy - quantified MetroMPG Aerodynamics 159 07-23-2019 04:48 PM
CdA list Daox Aerodynamics 161 05-27-2019 09:09 AM
Sources of Aerodynamic Drag in Automobiles and Possible Solutions SVOboy Aerodynamics 12 02-17-2010 03:09 PM
-- Bye Bye Side Mirrors -- Help me out basslover911 Aerodynamics 11 11-09-2008 03:26 PM
Bicycle side view mirrors? cfg83 Aerodynamics 2 02-15-2008 12:54 PM



Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2019, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com