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

Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 05-21-2012, 08:31 AM   #1 (permalink)
Deadly Efficient
 
Tango Charlie's Avatar
 
Join Date: Jun 2008
Location: Goshen, Indiana
Posts: 1,234

Olivia - '03 Pontiac Vibe base
90 day: 36.01 mpg (US)

R2-D2 - '00 Honda Insight
90 day: 58.81 mpg (US)
Thanks: 132
Thanked 175 Times in 91 Posts
The Corridor Effect

From the '100+ Hypermiling Tips';

14) The 'corridor effect'
All else being equal, traveling at a constant speed on a freeway within a flow of traffic (in the same direction) is more efficient than going the same speed in isolation. The reason is aerodynamic: a flow of traffic generates a localized wind current in the direction of travel. You will benefit from this artificial breeze.


This morning I was sixth in line behind a large truck. The other five cars were spaced somewhat evenly about 10 to 15 yards apart, which I mentally noted as being out of the ordinary. Usually they instinctively bunch up on each other. (I also just realized that I was using my Marlin Perkins voice while making that mental note...)
I have enjoyed the benefits of drafting and the corridor effect before, but this morning's circumstances were quite pronounced. I was able to cruise along about 20 to 25 yards behind the procession and noted much less throttle needed, and corrospondingly the Insight's instantaneous MPG reading was significantly higher than usual along that stretch of my commute.
Has anyone else enjoyed the corridor effect?

__________________
-Terry
  Reply With Quote
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 05-21-2012, 09:21 AM   #2 (permalink)
Rat Racer
 
Fat Charlie's Avatar
 
Join Date: May 2011
Location: Route 16
Posts: 3,299

Al the Third, year four - '13 Honda Fit Base
Team Honda
90 day: 42.9 mpg (US)
Thanks: 1,251
Thanked 1,354 Times in 874 Posts
Yep. But it's more fun with Steve Irwin's voice.
__________________

Quote:
Originally Posted by sheepdog44 View Post
Transmission type Efficiency
Manual neutral engine off.100% @MPG <----- Fun Fact.
Manual 1:1 gear ratio .......98%
CVT belt ............................88%
Automatic .........................86%

  Reply With Quote
Old 05-21-2012, 12:08 PM   #3 (permalink)
...beats walking...
 
Join Date: Jul 2009
Location: .
Posts: 6,191
Thanks: 179
Thanked 1,521 Times in 1,122 Posts
Quote:
Originally Posted by Tango Charlie View Post
From the '100+ Hypermiling Tips';

14) The 'corridor effect'
All else being equal, traveling at a constant speed on a freeway within a flow of traffic (in the same direction) is more efficient than going the same speed in isolation. The reason is aerodynamic: a flow of traffic generates a localized wind current in the direction of travel. You will benefit from this artificial breeze.

Has anyone else enjoyed the corridor effect?
...NASCAR drivers do every race day, following the car ahead by mere inches at 150+ mph speeds, even the last car in the "train."
  Reply With Quote
Old 05-21-2012, 12:16 PM   #4 (permalink)
Drive less save more
 
ecomodded's Avatar
 
Join Date: Jul 2011
Location: Vancouver Island, Canada
Posts: 1,189

Dusty - '98 VOLKSWAGEN Beetle TDI
TEAM VW AUDI Group
90 day: 60.42 mpg (US)
Thanks: 134
Thanked 162 Times in 135 Posts
I also notice the effect but its usually detrimental to my mileage because the flock of cars is always traveling faster then my preferred speed, under 60. I agree its unusual to see cars spaced neatly apart floating down the highway, more often then not there is a mini race circuit with AL Unser jr. fighting for position. I like to find a slow moving semi, rv or uhaul and use him as my wind break.
If i had to choose a voice over for my announcer it would have to be Howard Cosell announcing the speeding cars position in their run away pack, they seem to be so serious.
__________________
Save gas
Ride a Mtn bike for errands exercise entertainment and outright fun
__________________



  Reply With Quote
Old 05-21-2012, 12:42 PM   #5 (permalink)
PSmodder lurker
 
Join Date: Jan 2009
Location: Chino
Posts: 1,507
Thanks: 23
Thanked 776 Times in 452 Posts
On some long distance drives, I've 'attached' to some multi-vehicle (usually three cars) convoys. Admittedly not eco, we have been faster than the usual traffic but it was done with very smooth lanes changes. Rabbit, middle & tail-end Charlie changes every once in a awhile. It kept you more alert than usual and very aware of traffic dynamics far far ahead in the distance.
In eco-mode, (when you've already done a couple of hours of driving) I've attached to multi-truck convoys that have a very steady rate on the right lane. Unfortunately, very numbing experience.
  Reply With Quote
Old 05-21-2012, 12:55 PM   #6 (permalink)
Master EcoModder
 
skyking's Avatar
 
Join Date: Apr 2011
Location: Tacoma WA
Posts: 1,270

Woody - '96 Dodge Ram 2500 SLT
Team Cummins
90 day: 23.82 mpg (US)

Avion and Woody - '96 Dodge/Avion Ram 2500/5th wheel combo
90 day: 15.1 mpg (US)

TD eye eye eye - '03 Volkswagen Beetle GLS
90 day: 49.05 mpg (US)

Mule - '07 Dodge Ram 3500 ST
Thanks: 552
Thanked 455 Times in 294 Posts
Quote:
Originally Posted by ecomodded View Post
I also notice the effect but its usually detrimental to my mileage because the flock of cars is always traveling faster then my preferred speed, under 60. I agree its unusual to see cars spaced neatly apart floating down the highway, more often then not there is a mini race circuit with AL Unser jr. fighting for position. I like to find a slow moving semi, rv or uhaul and use him as my wind break.
If i had to choose a voice over for my announcer it would have to be Howard Cosell announcing the speeding cars position in their run away pack, they seem to be so serious.
That's why I dig the open highways and the trucks at 60. I keep back and over a bit to one side so they see me. I figure the negative aero effect is offset by not being an A-whole. karma points count in my book.
__________________




2007 Dodge Ram 3500 SRW 4x4 with 6MT
2003 TDI Beetle
2002 TDI Beetle

currently parked - 1996 Dodge 2500 Cummins Turbodiesel
Custom cab, auto, 3.55 gears
  Reply With Quote
Old 05-21-2012, 06:25 PM   #7 (permalink)
Master EcoModder
 
aerohead's Avatar
 
Join Date: Jan 2008
Location: Sanger,Texas,U.S.A.
Posts: 10,101
Thanks: 15,246
Thanked 5,377 Times in 3,165 Posts
airships

In the 1920s and 30s,during 'coastdown' tests of Paul Jaray's- designed Zeppelin LZ-126 (USS Los Angeles),Wolfgang Klemperer and NACA (NASA) testers had to include this mass of air which traveled along with the airship in the drag calculation.
19th-century race hull designers observed it on ships.
Railroad train drag testing reported on such a thing with respect to the boundary layer.
Hucho has a section on 'convoy' driving which doesn't directly mention a 'corridor effect',although it would be embedded within the phenomenon.
  Reply With Quote
The Following User Says Thank You to aerohead For This Useful Post:
gone-ot (05-21-2012)
Old 05-21-2012, 06:30 PM   #8 (permalink)
...beats walking...
 
Join Date: Jul 2009
Location: .
Posts: 6,191
Thanks: 179
Thanked 1,521 Times in 1,122 Posts
aerohead -- excellent comment, I'd totally forgotten about the "trains-in-tunnels" and their (basically) 360-degree "corridor" effects.
  Reply With Quote
The Following User Says Thank You to gone-ot For This Useful Post:
aerohead (05-23-2012)
Old 05-21-2012, 10:18 PM   #9 (permalink)
Master EcoModder
 
Join Date: May 2012
Location: Indiana
Posts: 1,513

Volt, gas only - '12 Chevrolet Volt Premium
90 day: 38.02 mpg (US)

Volt, electric only - '12 Chevrolet Volt Premium
90 day: 132.26 mpg (US)

Yukon Denali Hybrid - '12 GMC Yukon Denali Hybrid
90 day: 21.48 mpg (US)
Thanks: 160
Thanked 333 Times in 232 Posts
ill actually drive faster if i have to in order to stay behind someone rather than push my own air. even while going faster i get better mileage. i.e. rather than going 60(speed limit), i might go 65 or 70 if it means staying behind someone.

btw, i do NOT drive too closely, plenty of braking distance. no less than 50ft, typically about 75-100ft if i had to guess.
__________________




  Reply With Quote
Old 05-22-2012, 07:58 AM   #10 (permalink)
Deadly Efficient
 
Tango Charlie's Avatar
 
Join Date: Jun 2008
Location: Goshen, Indiana
Posts: 1,234

Olivia - '03 Pontiac Vibe base
90 day: 36.01 mpg (US)

R2-D2 - '00 Honda Insight
90 day: 58.81 mpg (US)
Thanks: 132
Thanked 175 Times in 91 Posts
Yeah, I agree, ksa8907. Just this morning again, I was third in line behind a tanker and was able to blast along at 60, getting what I usually get at 52 mph by myself. It helps not P.O.ing traffic behind; the whole karma thing like skyking mentioned.
But the corridor, in my mind, is different than drafting. Related, but different. You can trail quite a bit further back when you're in a corridor.

Interesting comment about the airships, aerohead. I'm thinking it was primarily due to skin friction drag? A lot of surface area on those monsters.

Oh, and Howard Cosell would make an excellent replacement for Marlin Perkins; Steve Irwin is just a little too excitable for me. Ha ha! I'm showing my age.

__________________
-Terry
  Reply With Quote
Reply  Post New Thread


Thread Tools




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