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

Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 07-02-2008, 06:43 PM   #1 (permalink)
Master EcoModder
 
Join Date: Jun 2008
Location: Earth
Posts: 5,209
Thanks: 225
Thanked 804 Times in 590 Posts
Mod for interior airflow?

Question for the aerodynamics experts: I've been reading arguments about windows down vs A/C, and just had a thought. You have a high pressure area somewhere at the front of the car, and a low pressure area at the rear. Suppose you take some - potentially a lot more than current vents supply - air from the front, and direct it through the car. You get the same cooling effect as rolling down the windows (if not a good deal more), some "wind in your face" effect a la convertible, no frigid breeze as with A/C... and it seems you'd actually reduce overall drag.

Make sense? Or am I missing something?

  Reply With Quote
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 07-02-2008, 06:50 PM   #2 (permalink)
Dartmouth 2010
 
SVOboy's Avatar
 
Join Date: Nov 2007
Location: Hanover, NH
Posts: 6,427

Vegan Powa! - '91 Honda CRX DX
Team Honda
90 day: 66.52 mpg (US)
Thanks: 92
Thanked 114 Times in 82 Posts
Send a message via AIM to SVOboy Send a message via MSN to SVOboy Send a message via Yahoo to SVOboy
There have been a few attempts at this, two which I remember well.

In one tom attempted rolling down the windows and cracking the hatch, but ultimately found that while stopped having the hatch crack allowed fumes from the exhaust to sneak in.

In the second, back when dan kroushl drove a del sol, he could crack the windows and roll down the rear window to get a similar affect.
  Reply With Quote
Old 07-02-2008, 06:50 PM   #3 (permalink)
Dartmouth 2010
 
SVOboy's Avatar
 
Join Date: Nov 2007
Location: Hanover, NH
Posts: 6,427

Vegan Powa! - '91 Honda CRX DX
Team Honda
90 day: 66.52 mpg (US)
Thanks: 92
Thanked 114 Times in 82 Posts
Send a message via AIM to SVOboy Send a message via MSN to SVOboy Send a message via Yahoo to SVOboy
There have been a few attempts at this, two which I remember well.

In one tom attempted rolling down the windows and cracking the hatch, but ultimately found that while stopped having the hatch crack allowed fumes from the exhaust to sneak in.

In the second, back when dan kroushl drove a del sol, he could crack the windows and roll down the rear window to get a similar affect.
  Reply With Quote
Old 07-03-2008, 12:55 AM   #4 (permalink)
Master EcoModder
 
Join Date: Jun 2008
Location: Earth
Posts: 5,209
Thanks: 225
Thanked 804 Times in 590 Posts
I think you would want to get a little more ambitious, and use ductwork (maybe flexible insulated furnace duct, to avoid picking up engine compartment heat) to lead from the intake to interior, then more duct from the rear of the passenger compartment to the outlet, with a backflow preventer so you don't get exhaust eddies.

My Insight does have something like the exit half of this, with vents on the rear (under the plastic rear shell) that close with flapper valves.
  Reply With Quote
Old 07-03-2008, 12:59 AM   #5 (permalink)
(:
 
Frank Lee's Avatar
 
Join Date: Jan 2008
Location: up north
Posts: 12,585

Blue - '93 Ford Tempo
Last 3: 27.29 mpg (US)

F150 - '94 Ford F150 XLT 4x4
90 day: 18.5 mpg (US)

Sport Coupe - '92 Ford Tempo GL
Last 3: 69.62 mpg (US)

ShWing! - '82 honda gold wing Interstate
90 day: 33.65 mpg (US)

Moon Unit - '98 Mercury Sable LX Wagon
90 day: 21.24 mpg (US)
Thanks: 1,530
Thanked 3,366 Times in 2,120 Posts
The ventilation system is already set up that way.
__________________


  Reply With Quote
Old 07-03-2008, 01:00 AM   #6 (permalink)
Dartmouth 2010
 
SVOboy's Avatar
 
Join Date: Nov 2007
Location: Hanover, NH
Posts: 6,427

Vegan Powa! - '91 Honda CRX DX
Team Honda
90 day: 66.52 mpg (US)
Thanks: 92
Thanked 114 Times in 82 Posts
Send a message via AIM to SVOboy Send a message via MSN to SVOboy Send a message via Yahoo to SVOboy
One thing I have though about doing it cutting out the bottom of the back bumper and redirecting air up into the wake.
  Reply With Quote
Old 07-03-2008, 12:52 PM   #7 (permalink)
Mechanical Engineer
 
Join Date: Jun 2008
Location: Richmond, VA
Posts: 190

The Truck - '02 Dodge Ram 1500 SLT Sport
90 day: 15.15 mpg (US)

The Van 2 - '06 Honda Odyssey EX
90 day: 19.49 mpg (US)

GoKart - '14 Hyundai Elantra GT base 6MT
90 day: 31.31 mpg (US)
Thanks: 0
Thanked 7 Times in 6 Posts
Both my 2002 Ram and my 1988 Ramcharger work this way. The ventilation system draws air from the high pressure area at the base of the windshield. In my Ramcharger I have a really cool vent that opens by hand and lets this high-pressure air blow up your left leg. Completely without a blower, just pushed by air pressure.

In my 2002 Ram the back of the cab has vents that allow air to escape between the cab and bed which is a low-pressure zone due to the flow separation at the rear of the roof above this gap. In my Ramcharger, the whole truck leaks so much air out the rear hatch and through the doors that the air blown in from the front is free to escape to the lower-pressure air to the sides and behind.

I really don't think this is much of a new idea. Cars without significant aerodynamic aids generate lift and therefore the air inside the cabin is at a lower pressure than the air from the front. Going back into the 30-60s vehicles with the cowl-vent open to adjustable sliding or turn-knob floor vents allowed outside air to flow in due to dynamic pressure differential. The addition of vent windows magnifies this and adds some flow to the upper body when opening the vents widely, but that really hurts your aerodynamics. The prevalence of climate-control systems in modern vehicles has replaced the need for such low-tech devices in the marketplace, making them absent even on the few vehicles that can be obtained without climate-control (are there still any?)
__________________
  Reply With Quote
Old 07-03-2008, 01:10 PM   #8 (permalink)
Master EcoModder
 
wagonman76's Avatar
 
Join Date: Jun 2008
Location: Northwest Lower Michigan
Posts: 1,006

Red Car - '89 Chevrolet Celebrity CL 4 door
Team Chevy
90 day: 36.47 mpg (US)

Winter Wagon - '89 Pontiac 6000 LE Wagon
90 day: 28.26 mpg (US)
Thanks: 8
Thanked 16 Times in 15 Posts
What Ive done for years is open the front and back (door) window the same amount. It keeps me from getting blasted, and therefore I would think it would also reduce turbulence.
__________________

Winter daily driver, parked most days right now


Summer daily driver
  Reply With Quote
Old 07-03-2008, 01:52 PM   #9 (permalink)
Master EcoModder
 
aerohead's Avatar
 
Join Date: Jan 2008
Location: Sanger,Texas,U.S.A.
Posts: 10,347
Thanks: 15,759
Thanked 5,504 Times in 3,272 Posts
interior airflow

Quote:
Originally Posted by jamesqf View Post
Question for the aerodynamics experts: I've been reading arguments about windows down vs A/C, and just had a thought. You have a high pressure area somewhere at the front of the car, and a low pressure area at the rear. Suppose you take some - potentially a lot more than current vents supply - air from the front, and direct it through the car. You get the same cooling effect as rolling down the windows (if not a good deal more), some "wind in your face" effect a la convertible, no frigid breeze as with A/C... and it seems you'd actually reduce overall drag.

Make sense? Or am I missing something?
Germans beat you to this 70-years ago! You need to track down a copy of Baron Reinhard von Fachsenfeld's "Aerodynamiks des Kraftfahrtzeugs" ( sp? ).It's all in there.I listed the particulars for the book in my seminars and installments.Inter-library loan is a good bet.I had to drive 30 miles to a university and copy it there.Good luck!
__________________
Photobucket album: http://s1271.photobucket.com/albums/jj622/aerohead2/
  Reply With Quote
Old 07-03-2008, 02:32 PM   #10 (permalink)
Legend in my own mind
 
trikkonceptz's Avatar
 
Join Date: Apr 2008
Location: Homestead, Fl.
Posts: 927

Evil Pumpkin - '08 Scion xD RS 1.0 #1633
90 day: 35.45 mpg (US)

Silent Silver Killer - '10 Honda Insight EX
90 day: 51.5 mpg (US)
Thanks: 2
Thanked 13 Times in 12 Posts
In a different topic on bellypans, someone said that aluminum screening would work well as a bellypan because the air would flow over it while allowing heat to escape.

Well along those lines I was thinking of making window screen that would use the glass and window channel along with a lighweight frame to hold it all together. Hence giving me the open window I desire while pushing air over it and not in my car. Don't know if it would work, but hell, once I am done with the pan, I'll use any extra material to try it out.

__________________
Thx NoCO2; "The biggest FE mod you can make is to adjust the nut behind the wheel"

I am a precisional instrument of speed and aeromatics
If your knees bent in the opposite direction......what would a chair look like???





  Reply With Quote
Reply  Post New Thread


Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Potential engine mod? Otto to Atkinson conversion AndrewJ EcoModding Central 84 09-23-2014 06:13 PM
Myth Busters SUCKS! (HHO mod, does it work?) markjs The Unicorn Corral 293 12-19-2012 02:55 PM
Testing the IAT mod tasdrouille General Efficiency Discussion 6 09-27-2009 04:09 PM
Quick and easy licence plate aerodynamic mod :D blackjackel Aerodynamics 7 05-13-2008 07:20 AM



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