Request: Pics of Full Underbody!!!

[Dackelone]

That last shot is a 1M.

Originally Posted by Mr Kleen

And the 1M battery box, and the 1M charcoal cannister, and the 1M heat shielding, and enough other parts that everything you're seeing is a 1M. The trunk area looks too small, to my eyes, to be a 3er.

Also, the jpg is "eisenmann_exhaust_1m....jpg"

Come on, Dak. You know this stuff better than I do!

I guess you did not read my PS note UNDER that photo? READ.

PS: this last shot I think might be of a M3 and not a 135i ? I think the finned diff is a clue. ?

[BrokenVert]

Originally Posted by eduz

BrokenVert thank you very much for your reply. Could you please indicate me the right section where i can open the topic?
I tried in the Photo section but i don't know why i don't have the permission!

(sorry for the off topic)

I would just try general. However I doubt youd find much help there. I cant think of any CAD models out there for the E8x, let alone the F2x.


You can find scale models from BMW. I would recommend doing a few 2D CAD models as these would only take a week or two to build, then you could compare your CAD flow results to wind tunnel results. You could mount a pitottube array onto one of the larger BMW scale models and take it from there.

The only problem I can see with that idea is that your typical flow solvers, like ANSYS/FLUENT, solve for lift and drag coefficients based on dynamic pressure (1/2*rho*u^2). In automobiles the drag coefficient is solved in a different way, its based on the frontal planar area of the vehicle, not the lift.

So building a 2D CAD model will give you a decent idea of flow velocities and youll be able to build a pretty good velocity contour out of it, and BMW gives Cd values - its 0.34 for an E8x car.


Also, the bottom of a BMW is pretty smooth as BMW puts plastic undertrays that cover the vehicle. So modeling it as a smooth wall would not be a terrible assumption.


Again, is this for a dissertation? Or is it for something else?

[Mr Kleen]

Originally Posted by Dackelone

I guess you did not read my PS note UNDER that photo? READ.

Oh, I read it. It was wrong.

[eduz]

BrokenVert, i'm sorry ' haven't reply to your question.... it's not for a dissertation but only for a presentation of an exam about aerodynamic.
I thought there could be some typical photos of the F20 inside a wind tunnel (so that it could not be necessary to use a cfd model), and of the underbody of the car.

Thanks!

[NORAGRETS]

anyone have a STOCK picture of the undercarriage? Think i just lost a little piece, want to see pic pls?

[Yeineken]

My car is on the lift right now. I might be able to get a full under carriage pic.

[Matticus91]

Originally Posted by Yeineken

My car is on the lift right now. I might be able to get a full under carriage pic.

Please do!!

[Matticus91]

I got my car on a lift and took pictures from back to front - yes, I know my car is filthy

20170830_110658 by Matt Steele, on Flickr
20170830_110703 by Matt Steele, on Flickr
20170830_110707 by Matt Steele, on Flickr
20170830_110711 by Matt Steele, on Flickr
20170830_110715 by Matt Steele, on Flickr