BMW Vision EfficientDynamics Concept 0.22Cd

[lunarhighway]

Cd is the new HP again... well maybe not, but a while ago noone cared even what a car's Cd was, now the numbers are bragged about again.

BMW Vision EfficientDynamics Concept



what's mainly interesting in this car for me is that it's roughly a 4 door sedan shape, and that it's got good aero, no mather what will power the car of the future, good aero will always improve FE.

although the back looks as impractical as it is beautifull in a sculpture sort of way, the rest of the flowing lines, and the shape between the wheels could easily be adopted by the next generation of BMW sedans.

anyway, it's good to see some carmakers are actively looking for ways to improve a cars Cd ... the 0.3 barier has been beaten a long time ago, so not the race for a sub 0.2Cd can begin!

[jkp1187]

This is a great vehicle. Definitely interested to see what bits of this car filter down to the more plebian vehicles. (And it would be very cool if they decided to produce this one, too!)

[lunarhighway]

yea at first it screams "concept car", but than when you imagine it in black...it wouldn't look that much out of place next to curent bmw's

things like the A pillars and the shape of the bonnet.

one thing that got me thinking however is that like some curent bmw's this car has an active grillblock.
What this basically means is that this car is going to have a variable Cd! it will have more air resistance with the grill open than closed and the difference could be rather big... so than how do you come up with a single Cd figure for the car?
do you take the lowest (tempting ) a 50% average or something calculated from the ammount a grill is open during a cerain test cycle?

[MetroMPG]

Originally Posted by lunarhighway

Cd is the now HP again... well maybe not, but a while ago noone cared even what a car's Cd was, now the numbers are bragged about again.

I suspect (hope) BMW is reacting to Mercedes' claims that it will dominate production cars' Cd figures in five years:

http://ecomodder.com/forum/showthrea...ears-8284.html

[wibiwo]

I don't believe it. The sunken headlights and grill, the sculpting on the sides, the wheel flares, the taillight tunnels, all that stuff is messing with the airflow. no way is that .20. Real cool looking, tho, especially the interior, in a '50's car-of-the-future way.

[RobertSmalls]

Yeah, concept car. But there's a few things to like about it: lower grille block, tiny gap between fender and tire, pretty smooth wheel covers, tiny mirrors, and a body that tapers in from above, below, left, and right. Only half of those features will survive the translation from concept car, so I wouldn't expect a Cd < 0.25, which still leaves room for this car to compete with the Prius.

The powertrain is probably more impressive. When I started reading about the 1.5L, 3-cyl diesel, I rolled my eyes and said "This is not a BMW." Then I got to the part about it producing 163HP, and having 356HP and 590 ft-lbs of torque when you add in the two electric motors. Wow.

Cut all those numbers to a third, and you'd have a very reasonable Prius-fighter. Of course, it wouldn't be a BMW.

[aerohead]

when BMW speaks many listen,and remains a significant influence on the entire industry.The very act of including Cd in official public communications lends "significance" to aerodynamics.I'll take that as a positive.

[winkosmosis]

Originally Posted by RobertSmalls

Yeah, concept car. But there's a few things to like about it: lower grille block, tiny gap between fender and tire, pretty smooth wheel covers, tiny mirrors, and a body that tapers in from above, below, left, and right. Only half of those features will survive the translation from concept car, so I wouldn't expect a Cd < 0.25, which still leaves room for this car to compete with the Prius.

The powertrain is probably more impressive. When I started reading about the 1.5L, 3-cyl diesel, I rolled my eyes and said "This is not a BMW." Then I got to the part about it producing 163HP, and having 356HP and 590 ft-lbs of torque when you add in the two electric motors. Wow.

Cut all those numbers to a third, and you'd have a very reasonable Prius-fighter. Of course, it wouldn't be a BMW.

Why cut those numbers to 1/3? What would be gained by having weaker electric motors and diesel?

[winkosmosis]

Originally Posted by wibiwo

I don't believe it. The sunken headlights and grill, the sculpting on the sides, the wheel flares, the taillight tunnels, all that stuff is messing with the airflow. no way is that .20. Real cool looking, tho, especially the interior, in a '50's car-of-the-future way.

All that is supposed to control airflow in a way that apparently reduces drag

Slender openings around the front air dam guide the air flowing specifically into two closed ducts leading inside the front air dam to the wheel arches where the air comes out again through a very slim aperture at high speed, flowing just next to the outer wheel flanks.

This air jet rests on the front wheels like a curtain and is therefore referred to most appropriately as the “air curtain.” It provides a highly stabilizing effect.

[lunarhighway]

it actually also reminded me of another car wich i couldn't put my finger on

the mazda taiki

perhaps not a direct visual link but there some of the same stuff going on at the back.
we all know a teardrop is a very eddicient shape, but somehow cars like the aptera do not convey a muscle car feel or sence of great "power"
also broad track 4 weeled vehicles are difficult to match with a teardorp shape
gm wen wrong there with the brutal volt concept and than had to back it of a bit.

i think the trick is to make a car wich looks powerfull and wide at the back to the eye but not to the air...

personally i think little by little the wheels are sepparating themselves from the body work... wich is ironic as it took them so long to finally become part of it