Double coanda exhaust?

[shelly]

I was taking a look at redbull double rear wheel strake (see topic: http://www.f1technical.net/forum/viewto ... 31#p426131)

and while I noticed that the fillets at the junction between strake and floor are much bigger on rbr than on the other cars, I asked myself a question: would it be a good idea to shape the trailing edge of the floor where the exhaust flows as a second coanda ramp. That would deflect the exhaust more downwards - and i think it could be beneficial for the notorius "seling effect"
Probably the ramp would not need to be very big, just a small upward part between the strakes followe by an arc, similar to the rear tyre sensors "bubbles" on the corners of the floor in front of the rear wheels.

[stez90]

There is a rotating tire near there, shouldn't it bend the flow downwards by itself?

[seventhsin]

And the lower pressure under the car 'pulling' the plume in?

[shelly]

Both effects are there: the dlow prseeure pulling air inside with the footplate vortex, and some downwash from the front part of the tire (that is combined with the downwash of the foot plate vortex).

Would it be an advantage if the exhausts flow was pointed lower to the ground? It could interact with tyre squirt at lower height, influencing the powerful contact patch vortex, and it would be pulled less to the inside of the diffuser. I think these two things could be good for downforce, but maybe I am ovelloking something

What we are seeing is that rbr, has introduced the double strake that induces one more vortex. That seems coeherent with the aim of increasing the downwash, but could also have another target