10% (AERO)Drag Reduction W/factory parts

[40X40]

10% CLAIMED (AERO)Drag Reduction W/factory parts

Link:
http://www.caranddriver.com/news/2013-volkswagen-jetta-hybrid-photos-and-info-news

Excerpt:

Visually, the Jetta hybrid is set apart from its siblings by a few aero modifications—including a new front air dam, a rear diffuser, and a spoiler—which combine for a claimed 10-percent reduction in drag.

It might be desirable to retrofit these parts to TDI Jettas in the future. This Hybrid Jetta is supposed to go on sale before the end of 2012 and I assume we can purchase these parts sometime shortly after.

Enjoy,

Bill

 

[NarfBLAST]

I don't believe anything I read anymore. A spoiler that reduces drag? REEEEAAALLLLYYY?

Also, there is no way in hell those are 15 inch wheels, or that VW will ever release anything with 15" wheels in North America. Americans will not stand for anything less that 16" wheels don't you know.

edit: just checked vw.com, appearantly you can still get 15" steel wheels on base model, wow!

 

[otb4evr]

I don't believe anything I read anymore. A spoiler that reduces drag? REEEEAAALLLLYYY?!

I will take this comment as either sarcasm or trolling...

Jim

 

[NarfBLAST]

No really, I thought all spoilers on trunk lids increased drag in order to add down-force? How is it possible that lip on the trunk lid in those pictures does not "spoil" the laminar flow coming off the back of the car? Is that not the definition of a spoiler? Am I missing something here?

This whole 10% claim smells fishy.

 

[otb4evr]

No really, I thought all spoilers on trunk lids increased drag in order to add down-force? How is it possible that lip on the trunk lid in those pictures does not "spoil" the laminar flow coming off the back of the car? Is that not the definition of a spoiler? Am I missing something here?

This whole 10% claim smells fishy.

Ah... I get it...

What about the little spoiler on the top of the Sportwagen? Is it there for downforce? Perhaps it helps the air not get stuck in a pocket on the back of the car...

IIRC Chevy got an additional 2 mpg out of aero work on the Tahoe Hybrid on the highway. It was so successful that they rolled out that package to the regular truck. It went from 20 mpg to 22 mpg....a 10% bump.

Jim

 

[whitedog]

And why the lip on the back of the 2004/2005 A4 Jettas? If that there for Aerodynamics?

 

[powerfool]

Minivans and SUVs (and wagons) have a differently oriented spoiler that directs air downward over the rear window. If it isn't there, you can notice that the window gets extremely dirty. This is because a vacuum is created back there and particulates get pulled in. This vacuum acts as a bit of a force to keep pull the vehicle backwards (obviously, it isn't very strong as the vehicle is very successful at still moving forward). Anyhow, pushing that air down eliminate the vacuum.

The same thing happens to "regularly" shaped autos, as well, but to a lesser degree. A spoiler of some sort could eliminate that.

This is the same reasons that semi trailers are starting to use those fins on the back.

 

[deejaaa]

Minivans and SUVs (and wagons) have a differently oriented spoiler that directs air downward over the rear window. If it isn't there, you can notice that the window gets extremely dirty. This is because a vacuum is created back there and particulates get pulled in. This vacuum acts as a bit of a force to keep pull the vehicle backwards (obviously, it isn't very strong as the vehicle is very successful at still moving forward). Anyhow, pushing that air down eliminate the vacuum.
The same thing happens to "regularly" shaped autos, as well, but to a lesser degree. A spoiler of some sort could eliminate that.
This is the same reasons that semi trailers are starting to use those fins on the back.

yes, it creates a vortex that acts as a parachute. changing air flow puts it farther out thus not allowing it to create 'drag'.
here is a good read:
http://ecomodder.com/forum/showthread.php/roof-spoiler-pick-up-truck-cab-phase-1-a-19525-2.html

 

[powerfool]

I was reading an article today about aerodynamics and it suggests that most of the studies on aerodynamics are irrelevant to daily driven road cars; most are for race cars and aircrafts and these items don't apply.

For aerodynamics, 1/3 is exterior body, 1/3 is intake and cooling, and 1/3 is the underside of the car. Not a whole lot you can do for the exterior body or the cooling. For the underside, the front wheels create the most drag, followed by the rear wheels, and then the rest of the underbody. After performing studies on a Japanese-market 99 Toyota Prius, placing baffles in front of the wheels had a minimal impact. The best impact is an underbody plate that incorporates the benefits of the baffles right in... so, essentially a skid plate and mounts flushly up front and contours out and down to direct air away from the front wheels. I believe they were looking at a 10% increase in fuel economy on a car that already had a pretty smooth underbelly.