|
Hi,
I'm pretty sure that this effect will vary for different vehicles? The slope of the windshield, the angle of the 'A' pillars, and the aerodynamics of the front of the vehicle will affect it. If the operable window opens just at the top, or if it opens also along the leading edge of the window, and how close it is the 'A' pillar, and the general flow of air in this area; will all possibly affect this tweak.
As some have already said, even if the FE doesn't improve -- if it helps with the air flow and doesn hurt the FE (much), then this will be a good technique for ecodriving, for sure.
I know that in my xA, if I open just the front windows, it has a different effect than if I also open the rear windows; or just the rear windows. If I open just one rear window too much -- I get this massive low-frequency "beating" that pummels the eardrums! Conversely, I can open just the front windows all the way up to say 45mph, and get almost no additional noise at all.
|