Super circulation: possibility to gain downforce

[godlameroso]

They'll lose some low speed downforce next year, they'll also lose the mandatory weight distribution. This, in addition to what they have learned throughout the year, I could very much see them being as fast as this year, maybe even faster.

[Sonic59]

So, as I promised, I made "near ground" simulation and here are the results.
Near the ground effect was so strong that flow separation was even at negative AoA. So I was forced to change airfoil, add slat and reduce jet stream angle.
First picture:
no ground, AoA = 20deg, stream angle = 60deg, steam speed = 300m/s, V = 30m/s, Cl = 3.6, Cd = 0.98

Next we add moving ground below airfoil like that:

And now what we get:
AoA = 10deg, stream angle = 60deg, steam speed = 300m/s, V = 30m/s, Cl = 5.9, Cd = 0.054

Next we add moving ground above airfoil like that:

And now what we get:
AoA = 10deg, stream angle = 60deg, steam speed = 300m/s, V = 30m/s, Cl = 4.1, Cd = 0.21

As a conclusion I'd like to say that ground has significant effect on circulation. Even we twice reduce AoA, we still have more lift/downforce. However we can see that when ground is below airfoil we have 1.5 times more aerodynamic forces.
In both cases "near ground" we have significant Cd reduction.

[Sonic59]

A little update:
AoA = 10deg, stream angle = 30deg, steam speed = 300m/s, V = 30m/s, Cl = 7.2, Cd = 0.08

It much more relevant to F1 and racing than previous pictures. Great reults so far. It's probably not the limit cause I have to try diffrent AoA/Stream angle combinations.

[Billzilla]

Retro-bump time.
Is it possible that this is what was being done with the no-banned F-Duct? I never believed the story that it 'stalled the rear wing' as that would create excessive drag. So instead of turning off the wing on the straights, as most said they did, it was 'on' all the time but when the port was uncovered it allowed extra airflow onto the rear wing as per what is being discussed in this thread ... ?

[volarchico]

Retro-bump time.
Is it possible that this is what was being done with the no-banned F-Duct? I never believed the story that it 'stalled the rear wing' as that would create excessive drag. So instead of turning off the wing on the straights, as most said they did, it was 'on' all the time but when the port was uncovered it allowed extra airflow onto the rear wing as per what is being discussed in this thread ... ?

This was discussed in detail in the F-duct thread. I think the general consensus was that there was not enough energy in the flow to act like the jet being modeled by Sonic for the F-duct to operate in the manner you suggest.

[wesley123]

results seem pretty good but then we come to the next thing, where is it exactly applicable? Based on the flow field I think it is already used on the ferrari sidepods, although its function is different compared to what is done here.

[Sonic59]

results seem pretty good but then we come to the next thing, where is it exactly applicable? Based on the flow field I think it is already used on the ferrari sidepods, although its function is different compared to what is done here.

I don't want to post determined solutions for race car. Try your own ideas. Use your imagination.

[marekk]

Thank's for your CFD's, sonic59.

Results are quite as expected, maybe Cl gains a little on the high side (probably due to big difference in flows speeds).

The idea is not new, in fact there was lot of solid research in this area, wind tunnel tests included, and it is proven that there are Cl gains with very small Cd penalty to be found by blowing (or sucking) relatively small quantities of air from both low pressure side surface and trailing edge of the wing.

Common description of those systems is power augmented lift enhancement device, and as the name suggest they'll need power source.

With reintroduction of turbos they will have a handy source of high pressure air, but under current (and probably feature) rules not much use of this - no holes/slits in wing profiles allowed at all (no more then one section in any longitudinal cross section, if i remember correctly ).

[PNSD]

What post-processing program did you use for these btw?

Also, any pictures of the mesh? Results look good. Have you altered the position of the blowing at all? ie, along the surface of the aerofoil?