View Single Post
Old 11-07-2022, 10:49 AM   #36 (permalink)
aerohead
Master EcoModder
 
aerohead's Avatar
 
Join Date: Jan 2008
Location: Sanger,Texas,U.S.A.
Posts: 16,269
Thanks: 24,393
Thanked 7,360 Times in 4,760 Posts
'big difference'

Quote:
Originally Posted by AEOLUS View Post
I dont know in which wind tunnel is meassurments done..
CLA has 1480kg, Merc. claim 180 blue efficiency has Cd=0.22 and 250CDI in test has shown Cd=0.30.
This two cars are 99.9% identical, to me is strange so big difference in Cd.
What do you think?
In 2013, BMW's i8 also registered Cd 0.22, in CFD.
Kalheinz Ebbinghaus, aerodynamics engineer on the BMW i8 commented that ' Thirty to forty percent of a car's aerodynamic resistance is created in the wheels and housings,' ( up to Cd 0.088 with the i8 ).
That easily covers the variability of the CLA if we ignore the A2 Wind Tunnel data. And I recommend we consider only numbers from the M-B tunnel.
__________________
Photobucket album: http://s1271.photobucket.com/albums/jj622/aerohead2/
  Reply With Quote