new mercedes b class 0.24 Cd
 

http://i77.photobucket.com/albums/j5...jbvxgz_600.jpg

0.24Cd for the eco version 0.26 for the normal version
(dutch source ) looking for more confirmation, but when the car is released those numbers are usually part of the mercedes tech sheet
the only interesting aero feature that jumps out to me is the smooth sloping undertray, seems gm might be on the wrong track with their pavement scraping airdams

i think the boxfish studie is paying off

Nice. I hope it comes with a diesel. :)

From the linked page.

>

...in the US. :(

Things that make you go Hmmm.

http://i54.tinypic.com/xksvfo.jpg


Are MB Engineers looking in on Ecomodder???
FWIW, That is a very exact duplicate of the aerotemplate simply scaled to fit as Aerohead has recommended. I did NOT change a thing to make it match.

someone know what they're doing :)

here's another shot of the front
http://i77.photobucket.com/albums/j5...-B-Class-1.jpg

its interesting to note the car seems to sit pretty low, but there's not an airdam in sight, is with previous mercedes producs i'm sure the underside will be pretty smooth

oddly the rear seems to feature rounded edges, the airflow is perhaps subtly controlled by ridges caused by the rear pannels.

the original concept of this car had transparant partial rear wheel skirts... perhaps mercedes is "softening up" their custommers to the idea. but taking or chuck out of that reat wheel arch (or rather not doing so) wouldn't have looked bad imho

http://rumors.automobilemag.com/file...lustration.jpg

http://wot.motortrend.com/files/2011...ics-detail.jpg

This new flap before or on the side of the tire looks interesting.

http://1.bp.blogspot.com/-a_0Hyy3Gar...-w-246-322.jpg

I think that the underside is where they have made their most gains in CD. Also if your cars underside is well designed it does not make any harm to push air also there. If you have very sharp lip on the spoiler there will be turbulece right under it. In my opinion the MB has enough smoothness in their bellypan. It creates similar venturi reaction that in sports cars and accelerates air flow...

Notes on the outer side that is best video I could find because its "slow motion":
http://www.youtube.com/watch?v=p84TrRK4Rco

- Front bumber directs the air slightly pass the front tire. Same on the rear tire
- Front side panel is slighly more inner than front tires outer rear edge
- On rear tire the rear bumber has about that 10 degree slope and its designed so that it will go about tangent rear tires outer edge.
- Rims are quite aerodynamic with little bit of covex shape in them.
- I believe mirrors are the same as in E class. Design them good in one car and you can use them in other similar models.
- And the most important feature that template C roofline like ChazInMT pointed out.

more info
2012 Mercedes B-class is low-drag champion | cartechnical.co.uk

Probably no chance of a diesel in the US.

Hmmm
 

I've been looking at car mags,and when they show good side photos in true-length,I'm seeing many,many new and future cars doing the 2.5:1 aft-body.
Even Porsche has given up on the Lange body with the up-coming 918 Spyder.
I think the CAFE standards are forcing them into scientific styling.
Some of the Lamborghinis aren't even putting rear spoilers on.There isn't any separation to 'fix.'
Ferrari's Italia
Honda's R-Type
Cadillac CTS Wagon
Leaf
Leaf NISMO
AUDI
Aston Martin
Even BMW's Rover is cutting the roof down on the Mini Cooper
Maybe,when aero is good enough for James Bond,it will be good enough for Joe Sixpack:confused:

I call shenanigans.

Perhaps if I leave my computer on overnight I'll see the pics Vekke put up tomorrow? Would a downward resize hurt the detail any?

The slope of the roof line is very similar to the Golf and many other hatchbacks.
Its a shame so many of them are content on staying at a .32 Cd .

http://img2.netcarshow.com/Volkswage...llpaper_07.jpg

http://i54.tinypic.com/xksvfo.jpg

i think the B class is a little larger than the golf, and the previous b class was a little higher than this model too, so mercedes had some room to lower the seats and free up some headroom that could be sacrificed for a better aero shape.

if the golf would have the same roofline as the B-class this would either impact rear passenger headroom, or if they chose to raise the front of the roof could increase frontal area.

but that said the comparison shows that with minimal changes in overall shape large differences in drag can be acieved. and with some carefull wiggeling a good compromise should be possible

i suppose this is why there's SUV's and crossovers comming out with rather surprising good drag coefficient, with their visual high stance it's easy to give or take a few centimeters to get a perfect roof profile, and a Cd that gives the impression they are as slippery as the sedan next to them (Cd x frontal area is still way over the heads of most buyers) especially when around 0.3 cd's are still marketed as "exeptional for it's class, etc..."

Vekke -

Hmmmm. I vote quasi-vortex generators. But I'm guessing you'd need a wind-tunnel to adapt them to your car.

CarloSW2

i find that shape *extremely* interesting

a while ago i started a thread on sawtooth trailing edges,
http://ecomodder.com/forum/showthrea...html#post59665
and this sort of borders on that idea. i imagine we might see more "magic" lumps and bumps appear on cars in the future.

perhaps this sort of idea might also work on front airdams, giving them "teeth" might produce a smoother and tighter flow pattern.... mmm might just try that

lunarhighway -

Ha ha, Landshark!

CarloSW2

It just shows Phil's template is very close to the money, regardless of what wink-whatever says.

You could do this exercise with a bunch of recent European cars, they'll all be close.

Mercedes ditched the sandwich bottom construction of the earlier A / B, allowing them to lower the new B class.

I'd love to see a tuft test on this car. I'm very curios about the airflow near those side creases.

It looks as if the Golf has pretty much the exact same roofline slope as the B class. ( Yet is stuck at .31 Cd )

Cd
 

If the max camber point on the M-B was 'forward' of that for the VW,it would have undergone a bit more pressure recovery and it's base pressure would reflect in the lower Cd.Just thinking out loud.

Thanks Phil !

I can't detect a difference except that the MB has a longer roofline which extends out farther at the back.

The MB also has a slightly flatter windshield than the VW, so the VW actually seems to match the template even more closely towards the front of the car.

I don't trust my sloppy overlay though. I think some of what i am seeing is the smoke stream.

The point of all of this being to show just how closely that cars match the MB , yet the VW is a full 7 counts higher.:mad:

plan view
 

If they would provide us with accurate plan view photos shot from above,we'd have a fair chance to better sort all this out.Thanks for images! Posting these things are my greatest challenge.

Hey Cd,

I drawed outlines on both a them there autobahnstormers, the VW Golf and MB B, and superimposed the outlines. I was very careful to not distort them, so I'm confident these template images are within 1/4" of the real cars thus representing true shapes.

In order to "Line them up" I had to choose between matching length, or matching height, I chose Height and I matched windscreen tops/ fronts of roofs. It just showed all the difference best.

http://i55.tinypic.com/6jj7us.jpg

4 things I notice.
1) The VW is Green and MB Red. :p
2) The hood area has a dramatic difference.
3) The bottom rear diffuser area is really different.
4) The MB has a few more inches of drop in its roof line and the peaks of the roofs are 12-18 inches apart. When I slid the MB back to try and match roof peaks, something interesting happened as well, the roof lines matched up. So indeed, MB has their roof peaking earlier.

So from the perspective of the roof peaks, the Golf has a lot more sticking out in front, and the MB has more sticking out the back, Hmmmmm.


http://i55.tinypic.com/jp8yvp.jpg

Hope this helps.

Thanks Chaz. You rock.
I believe the 92-95 Civic hatch has the same problem as the golf - the roofline does not slope down enough at the tail end of the car.

From the link posted by Fabio:

"A whole range of measures were necessary in order to attain the excellent
drag coefficient," explains Dr Teddy Woll, Daimler's head of aerodynamics at
Daimler AG. "Apart from an aerodynamically efficient basic design, these
include numerous optimisation measures on points of detail, such as the air
flow around the front wheels, the underbody design and the flow of cooling
air."

The aerodynamics of the 2012 B-class were optimised using complex
computer calculations and flow simulations which required more than 275,000
CPU hours. Models and prototypes spent around 1100 hours in the wind
tunnel.

I take it this means it will be difficult to duplicate/transfer the subtle
aerodynamic "optimisations" with Coroplast, duct tape and a box cutter. :mad:

It takes a whole lotta megaWatts to gain a few kiloWatts

That is what I have always been led to believe ...until I saw what AndrewJ did with his box cutter and some junk plastic sheeting. ( Even before the boat-tail )
He dropped his Cd from .31 down to .26 with just a few mods.
Also, i think back on the Hot Rod 'project red hat' Camaro. They did some wind tunnel testing on the car yes - but not thousands ( or even hundreds ) of hours in the wind tunnel. They got a pretty much stock looking '80 Camaro down to .20

Car Aerodynamics - Hot Rod Magazine

Why is this news? The E class coupe had a 0.24 CD 2 years ago. MB's stated goal is less than 0.20 by 2015.

http://i53.tinypic.com/2ajvu2o.jpg


Seems rather implausible given how that looks in the back.

Ha ! Love that.

http://www.hotrod.com/techarticles/b..._aerodynamics/

So did you read the entire article ? The car was tested in a wind tunnel run by a guy that worked with GM on the EV-1

I know what you mean though. Everything about that car seems an aero mess.

It has a barn door flat front end, gaping wheel wells and apparently was originally tested without even a belly pan. Even the body trim around the windshield looks to be an aero mess

Aerodynamik Report: Spritsparmodelle aus dem Windkanal - AUTO MOTOR UND SPORT

Does anyone know german language?

Google Translate

Did anyone discovered what includes the "ECO Technology" package? Pictures of them?

"These include lowering of the body, the sealing of joints at the rear window and the cladding of chassis components at the rear axle."

It seems that these little changes are not so much cosmetic in themselves as intended to accomplish some of what other more effective and easier mods might accomplish but also make the car "uglier" in the eyes of potential buyers. I'm thinking here about the comments about that .20 Cd camaro up above a few posts back in this thread. That car mainly used a thoughtfully designed but "garish" front airdam. Mercedes wouldn't want one of those on the new b-class!

Too bad the B class are never sold in the US. I work for Mercedes but they don't offer any car here that I would want to buy.

Very interesting belly pan, sort of wedge shaped, being lowest to the ground by the front wheels..

http://www.youtube.com/watch?v=KbGgj...eature=related

the new mazda 3 has a Cd of 0.26 - not bad! the point I wanted to make was that they show what the spoilers in front of the tires does - also on the b class.

Nice video. Thanks. The hole in those tire spats/spoilers seems novel. Is it to assist cooling brakes or maybe to minimize the enlarging of the effective frontal area by creating blasts of air to the sides? I was also struck by how they represented the installation of body panels under the car: they opted for spot panels instead of a full sized bellypan. The biggest panel covered the whole engine bay.

It streamlines the flow of air past the wheels.
BMW call it the Air Curtain - we've had a thread on that before.