MIT theory can finally predict 3D flow seperation.
 

Check out this article, up until now mathematically predicting flow separation has been a complete mystery. I'm not smart enough to know the practical impact of this, but I assume it means the design of low drag shapes (and vehicles) will become a lot easier and computation fluid dynamics will get a lot more accurate.
http://web.mit.edu/newsoffice/2008/f...f-enlarged.jpg

mattW -

Great find! I don't know what it means, but solving a 100 year old problem has to count for something.

CarloSW2

3-d
 

It's a great thing.Cheap computer energy can do the work once relegated to only really good windtunnels(which can use enough electricity to dim the lights of an entire city!) The windtunnel can do the final "visual" verification and dry laundry! Way cool!

Plus, all of us here obviously have computers, which can't be said for wind tunnels.

Random thought: I think the picture looks like an eyeball, out of the socket of course.

eyeballs
 

Looks like the eyeballs on that MIT interactive cuddly robot with fur.It's a MIT thing!

So it's been a year and a half since this MIT "discovery" was made. The article itself sure is light on technical content. Anyone know more? How exactly are we exploiting this knowledge? :)

Cheers
KB

exploiting
 

I suspect that this technology will remain in the domain of the automakers tech centers for some time before we'll gain access to it.Hope I'm wrong.
The other part of the equation,is how easy will it be to input the spherical coordinates when setting up the paneling of the body for the Navier-Stokes numbers-crunching to do its thing.

Well, the article mentions the equations were published in a journal. So once they are experimentally validated, expect them to show up behind the scenes in CFD toolboxes, some of which are open source and free to download.

Very interesting article! I note a couple of things:
1. A car has to deal with ground planes and there is no mention of them in this brief article.
2. Most interesting to me was the red and green areas of the graphic. The article mentions that the red lines represent "classic" computation of separation. The green lines represent the "new" theory. From the graphic it sure looks like unseparated flow exists much longer than we had thought SO LONG AS THE SHAPE TRANSITION IS GRADUAL. Don't know that "final" angle on the sphere, but it could be 30 degrees or so.

ground plane
 

I don't know about the angle,but I believe Hucho mentioned,that with CFD,they all use the 'mirror-image'/ 'ground-reflection' technique to allow for the ground effect.