Exhaust Blown Floor - Forward Exhaust Exit

[marekk]

I don't think one can significantly decrease drag by blowing all exhaust gases into low pressure wake behind front tyres - volume/mass flow of exhaust is simply to small compared to amount of air displaced by the tire, and at high speeds of the car, when drag reduction will give biggest gains, even more so.

Hopefully one day they fill to much oil in the tank and we will see.

How do you think the f duct works?

I just want to see a rain race or a night race.

By blowing reletively small amount of air under the flap/wing, already working on the very edge of the stall curve. Flow detaches from the surface, and downforce/drag reduces suddenly.

F-duct is just flow control device, it's not working by filing the void behind rear wing.

[ringo]

Strad we need some free practice shots of China FP1.
We can clearly see the FEE blowing the dust very rapidly to the sides. Check Heidfelds laps in the corners. The heat waves are also visible but the cleaning of the track by blowing the dust is the clearest.

[strad]

When Nick went off you can clearly see the exhauust blow dust as he blips the throttle at about 24 seconds...don't know if it's of any use, but it's intersting to see the exhaust coming out the side.
click photo

[govind112]

those commentators are awful lol

[ringo]

I was hoping for some high speed turn clips, but anyway this video is decent evidence though the car isn't moving so the exhuasts will blow through the sides without resistance from the free stream.

Practice 1 had some good camera angles in high speed turns.
If only someone had access to the full P1 and could track through it to find the earlier parts with heidfelds r31.

[Formula None]

Subjective image time!

Cropped & rotated from f1fanatic:





I only say subjective because I can't tell if the plume on the right side of the image is actually a plume, or part of a building in the background.

Also, I'm not sure where the heat waves are (in front of or behind the rear wheels).

Note that DRS appears to be activated,although its hard for me to tell at this camera angle.

[strad]

I got rid of practice...I'll see what qualifying has.

[strad]

Well I didn't see anything in qualifying,,,but I did get this bit from Renault...
click photo for video

[ringo]

Notice what he said about the downforce balance for and aft.
Not a lot of details but it's sufficiently helpful for the thread at least. It's an indication that the down-force is focused near the center of the car.

I think this is why Heidfeld was a little too confident in turn 1. He was flooring the car and giving it more gas even when he was 1/4 way through the snail.
The balance must have felt really good.


Where's marekk? I wanna see him explain this one.

[marekk]

Notice what he said about the downforce balance for and aft.
Not a lot of details but it's sufficiently helpful for the thread at least. It's an indication that the down-force is focused near the center of the car.

I think this is why Heidfeld was a little too confident in turn 1. He was flooring the car and giving it more gas even when he was 1/4 way through the snail.
The balance must have felt really good.


Where's marekk? I wanna see him explain this one.

You mean this plume clearly visible between step plane and left tyre ?
Or hot air behind the car ?

No magic in balance shift either. If you move your downforce form rear wing to diff/floor combo, it will shift forwards.

Heidfelds error was from overestimating the grip IMO. Going from retarded ignition to some throttle added could introduce some instability in flows too.

[ringo]

In my eyes my analysis is subsequently proven to be pretty accurate, backed up by two senior Renault staff.

Senior Staff don't phase me. Logic prevails; they mislead you.


Imagine if we, the air skirt conspiracists, withered under the insider big shot hearsay pressure?

A comment in science is not proof, neither can it back up anything. For example Ross Brawn or any big shot team principal saying a nose cone can pass a crash test, without actually doing any testing, cannot convince anyone. I wanna see that sucker crash into a wall before i believe it. They can equivocate like anyone else to protect their interests. .

Like wise this picture is confirmation of a logical analysis. Something we all saw with CFD and MS paint. Some refused to believe their eyes unfortunately.

So I think those Senior Renault guys were talking BS, and hiding what the car was really doing.

[Formula None]

The exhaust blows wider at low/zero airspeed.

Haven't seen video yet, does the steam hang around long or does it get lost quickly in the spray? Does it affect following cars or is it miniscule relative to loss of vision from spray?

[Giblet]

They had a thermal camera on the Mclaren during practise, but I didn't see the whole session. Have they pointed on at a recently ran Renault yet?

[Just_a_fan]

Like wise this picture is confirmation of a logical analysis. Something we all saw with CFD and MS paint. Some refused to believe their eyes unfortunately.

So I think those Senior Renault guys were talking BS, and hiding what the car was really doing.

Have you done a cfd analysis of the Renault itself or are you basing this all on a model made by forum member?

[Pierce89]

I don't think one can significantly decrease drag by blowing all exhaust gases into low pressure wake behind front tyres - volume/mass flow of exhaust is simply to small compared to amount of air displaced by the tire, and at high speeds of the car, when drag reduction will give biggest gains, even more so.

Hopefully one day they fill to much oil in the tank and we will see.

How do you think the f duct works?

I just want to see a rain race or a night race.

The F-duct works by using a flow perpendicular to the wing. This causes seperation which makes the wing less effective. This creates less downforce and less INDUCED DRAG.It does not work by trying to fill the low pressure with air to equalize its pressure. It would take a WHOLE LOT MORE mass flow to do that.