Ground effect in LMP1

[JotaBass]

Hi, a friend of mine asked me today if LMP1 cars have ground effect and i didn't know what to answer. Can you help me with the question?
And if they have, how important is it in generating downforce?
Thank you all!

[HampusA]

Tell him yes, but not the fan kind of downforce.

Just wings and diffuser is my guess.

[dumrick]

LMP's have ground effects. Here's a basic explanation of the concept, even though in recent times front diffuser extraction and a standard rear diffuser have made things evolve a bit:


You have now also a chanfered underbody, mandated by rules, with a plank, that is now different in shape and that has just been thickened by rules, raisng cars and limiting diffuser efficiency.


A brief explanation on the 2004 aero rules for LMP's, that are still the base of the current aero concept can be read here

[JotaBass]

Thanks a lot!
This is why i love this forum.

I also was wondering what is the relative importance of the underbody in downforce generation.