New car fashion or function

[ChazInMT]

I vote cosmetical, function maybe to help stiffen the panel, but aero wise, I can't see it doing much if anything.

[winkosmosis]

The character lines look like they hurt aero. I think they do add stiffness which might help a little in a side impact.

[Frank Lee]

Originally Posted by Shinjitsu

It would make sense that it would be at least somewhat functional. Most of us know, and if you don't your about to, that the wheel wells are an area where air is slowed down because of drag which makes that area a high-pressure area of the car. If you ever drive behind someone in the rain you can see the effects of this b/c there it a ton of mist and rain flying out of the wheel wells. So these body lines could be trying to suck that air out a little more and guide it to the place it is needed most - where the rear of the car creates a vacuum. If they can feed more air softly around the rear of the car, they can fill in part of that vacuum that is basically sucking the car back. Then again, the body line has been around for a while so it could just be a trend.

You get the prize for having the most vivid imagination.

[NeilBlanchard]

There may be some aero function, on some of the cars, at least. The wedge in front of the front wheel may serve to kick the air flow out and around the churning wheel? And the trailing crisp edge on the Prius behind the rear wheel forms a Kamm back of sorts. The Prius also has a vestigial rear wheel strake.

I think the hard chine along the fenders and doors is a bit of styling, that has virtually no aero "cost".

[Shinjitsu]

Originally Posted by Frank Lee

You get the prize for having the most vivid imagination.

Haha Thanks

[cfg83]

kach22i -

I think you're right the Celica. I disliked it at first as garish, but over time I grew to like it as the field "caught up".

CarloSW2

[jamesqf]

I vote for functional, by default. Can't be for style, 'cause it's ugly. Makes the car look even fatter in the rear than it actually is. Or maybe they're trying to appeal to the... oh, call it the chubby market to be kind. "Oh, look! That car has a fat butt, just like me!"

[endurance]

Well, I suspect it's a bit of both. Unlike the two examples kach22i put up, these 2010s and 2011s have a noticibly rising line to the crease, not just following parallel to the ground. I'd suspect they're trying to move air into the low pressure zone behind the rear window. The only 2010 I saw with this was the Prius, but now it's appearing everywhere including the new CR-Z (just saw my first one in the parking lot at work today).

I tried to look at highway MPG changes, but while every car I've noted got better MPG with the introduction of the upward wedge, they also all had changes in engines that probably played as big or a bigger role. The Prius, which doesn't appear to have had a change in displacement, had other changes which resulted in an increase in highway and city mpg by 3mpg.

[simondo]

My opinion is that it adds stiffness to the panels, and is also a styling exercise. I do not think it serves any aerodynamic purpose.

I looked at lots of cars on my way home today, and not all have these "lines", and the Seat has them going downwards!

[aerohead]

I vote 'structural',with creative license.
Daimler called it 'Zeppelinesque' I think.
The corrugation allows for stiffness in a thin,light,fuel-saving panel which would otherwise 'tin-can' or resonate.
The car skin can wad up in a collision absorbing kinetic energy of impact,leaving the safety cage and airbags as the 'barrier' to protect the occupants.
Any kind of crease adds the stiffness,so designers have a large degree of creative latitude in its use.
As to aero,I'll await an SAE Paper or journalistic synopsis of such a paper.