Tom888 wrote: ↑
Sat Mar 19, 2022 10:50 am
Why so low pressure at the "diffuser"/end of venturi tunnel(purple color)?
Here cant be so low pressure, this is place where pressure gradualy rise and meet car wake pressure(slighlty lower than freestream).
What will cause so low pressure at this area?
This is not such a low pressure at all, Cp of -1 is not that low in F1 terms. Overall, jjn did an amazing job modelling the car and Vyssion did an amazing job with CFD. Still, as they said, there is a lot more performance on actual cars, much lower pressure in the middle of the floor, especially with car running without the rake.
As Stu said, the air right before the diffuser exit is sucked out by the rear and beam wings, which is the reason for lower pressure at the exit here. Also, venturi-tunnels are very different from flat-floor diffusers, there shouldn't be a big fence-vortex in them to generate the low pressure, so low pressure in that zone is expected.