View Single Post
Old 06-24-2020, 01:19 PM   #28 (permalink)
aerohead
Master EcoModder
 
aerohead's Avatar
 
Join Date: Jan 2008
Location: Sanger,Texas,U.S.A.
Posts: 16,268
Thanks: 24,393
Thanked 7,360 Times in 4,760 Posts
diffuser

Quote:
Originally Posted by Taylor95 View Post
What do those strakes do?

So my Camry sort of has a 6" undertray extending from the front bumper. Could I do a rear diffuser only, or would that add drag?

Approximately how much would this lower Cd by?
A diffuser will only function if it's behind a viable full belly pan.
The pan, on the worst-case vehicle ( pickup truck/ SUV) is measured at delta- Cd 0.045 improvement.
A 'long' 2.8-degree up-swept diffuser will improve the drag reduction to delta-Cd 0.070.
A 'fast' 4-degree diffuser cuts drag a little less than the 'long' unit.
Any diffuser with an up-sweep steeper than 4-degrees is for high-speed sports cars, or racing.
------------------------------------------------------------------------------------
According to a research paper on the SAAB 9-3, the diffuser strake/guide vanes help mitigate effects of lateral wind gust, plus decrease turbulence effects due to rear wheels.
__________________
Photobucket album: http://s1271.photobucket.com/albums/jj622/aerohead2/

Last edited by aerohead; 06-24-2020 at 01:23 PM.. Reason: add data
  Reply With Quote