Aahmm... Not exactly correct..Just_a_fan wrote: β09 Jan 2020, 11:56If more air is being flowed along the top of the rear floor and over the top of the diffuser, you'll get a lower pressure on top of the floor, not a higher one. Improving airflow over the top of the diffuser makes it more effective and so gives the improved downforce.
Assuming Mercedes are moving their sidepods "up", I'd expect a RedBull-style design rather than a Ferrari-style design.
What you want at the back of the car is for the airflowto retain as much energy as possible (this reduces drag, and also allows you to use that air for other things).
The coke bottle air needs air with alot of energy so that it can utilized for the vortex generators at the side of the diffusers and the brake ducts, the gurneys the endpate and other devices..
So that is how the high velocity comes into play. The pressure is actually not low in that area because the velocity is still lower than free stream velocity in that coke bottle area. Usually the problems is the velocity is too slow if car design is really bad.