Radiator Drag - Fuelly Forums

Click here to see important news regarding the aCar App

Go Back   Fuelly Forums > Fuel Talk > General Fuel Topics
Today's Posts Search Click Here to Login
Reply
 
Thread Tools Display Modes
 
Old 08-07-2006, 09:46 AM   #1
*shrug*
 
Join Date: Sep 2005
Posts: 6,195
Country: United States
Radiator Drag

We all know the radiator causes hella drag, right? And we also know that a block is kewl for reducing that drag. However, what I'm wondering is does anyone have any information on how much drag it really is? I'm sure I've seen it somewhere, but I can't recall at all.

Reason I ask is I might be getting a half radiator and I'm wondering if it's worth having my friend fab up some mounts for it.
__________________

SVOboy is offline   Reply With Quote
Old 08-07-2006, 10:19 AM   #2
Driving on E
 
Matt Timion's Avatar
 
Join Date: Sep 2005
Posts: 3,110
Country: United States
Quote:
Originally Posted by SVOboy
We all know the radiator causes hella drag, right? And we also know that a block is kewl for reducing that drag. However, what I'm wondering is does anyone have any information on how much drag it really is? I'm sure I've seen it somewhere, but I can't recall at all.

Reason I ask is I might be getting a half radiator and I'm wondering if it's worth having my friend fab up some mounts for it.
Eh, do it... then you can get turbo :P

Or just send me the radiator so i can make the turbo-alternator one day
__________________

Matt Timion is offline   Reply With Quote
Old 08-07-2006, 10:28 AM   #3
*shrug*
 
Join Date: Sep 2005
Posts: 6,195
Country: United States
I'm pretty sure I could fit a turbo in with the full radiator, but I want the room just for bling factor as well. I'm pretty sure that one day I'll have a budget build crap crx for going to the track with and just pimp this one for FE/EV.
SVOboy is offline   Reply With Quote
Old 08-07-2006, 10:38 AM   #4
Registered Member
 
GasSavers_brick's Avatar
 
Join Date: Mar 2006
Posts: 162
Country: United States
One of the SAE papers that I have is dedicated to cooling-related drag. I'll take a look at it later to see if it offers any relevant info.
__________________
'07 Toyota Prius
GasSavers_brick is offline   Reply With Quote
Old 08-07-2006, 10:39 AM   #5
*shrug*
 
Join Date: Sep 2005
Posts: 6,195
Country: United States
Is it something of a linkable nature? I'd want to read the whole thing just to have the thing read,

Knowledge is empowering, after all.
SVOboy is offline   Reply With Quote
Old 08-07-2006, 11:42 AM   #6
Registered Member
 
MetroMPG's Avatar
 
Join Date: Dec 2005
Posts: 4,223
Country: United States
Cooling drag is significant enough that Mercedes has an E class with an active grille to match airflow to cooling needs, rather than always pay the price for airflow for worst-case cooling requirements:
http://www.sae.org/automag/globalvehicles/06-2002/

Active grilles are common on aero-aware concept cars.

For some numbers, try here:

http://www.tfd.chalmers.se/~lelo/rva...icles-drag.pdf

(I'm on dial-up at the moment and didn't want to wait for it to open to make sure the numbers are in there, but I think they are.)
MetroMPG is offline   Reply With Quote
Old 08-07-2006, 06:20 PM   #7
Registered Member
 
GasSavers_brick's Avatar
 
Join Date: Mar 2006
Posts: 162
Country: United States
I read through some of those papers and haven't found anything particularly pertinent. They focus more on cooling efficiency vs. aerodynamic efficiency, and as such don't say anything like "cooling air requirements account for xx% of aerodynamic drag." I haven't read word-for-word, though. There might be something non-obvious in there that I have yet to find.
__________________
'07 Toyota Prius
GasSavers_brick is offline   Reply With Quote
Old 08-07-2006, 07:36 PM   #8
Registered Member
 
MetroMPG's Avatar
 
Join Date: Dec 2005
Posts: 4,223
Country: United States
It's in there...

Quote:
Contribution to drag in a car comes from several factors, but in a general view can be considered having the following elements:

Surface friction, underbody and excrescences 0.08
Normal pressure 0.10
Effects of wheels 0.08
Eng cooling 0.03
Trailing vortex 0.01

Total 0.30
I've also seen an excerpt from a paper discussing Volvo aerodynamics claiming cooling drag represents 30% of total drag (but it doesn't say what kind/shape of Volvo...) I suspect for most of our small 4-cyl non-turbo cars, 10% is closer to the mark.
MetroMPG is offline   Reply With Quote
Old 08-07-2006, 07:39 PM   #9
*shrug*
 
Join Date: Sep 2005
Posts: 6,195
Country: United States
Half radiator here I come!
SVOboy is offline   Reply With Quote
Old 08-08-2006, 06:24 AM   #10
Registered Member
 
Join Date: Oct 2005
Posts: 682
Country: United States
Ever look at the radiators of large semitrailers? They all have what appears to be a canvas with a V shaped notch covering the radiator. At least in winter. Is reducing radiator drag that simple?
__________________

__________________
Capitalism: The cream rises. Socialism: The scum rises.
Sludgy is offline   Reply With Quote
Reply


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


» Fuelly iOS Apps
» Fuelly Android Apps
Powered by vBadvanced CMPS v3.2.3


All times are GMT -8. The time now is 12:52 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.