Downforce - how much?

[SuperSonic]

Hello,

How much downforce (in kg) do each part of a current f1 car generate? I mean the front wing, rear wing, diffuser and also the bodwork. I've heard that a car even without wings can generate enough downforce to run upside down, is this true?
I do know that wings efficiency depends on the airflow, if it is "clean" or not, etc... I'm just curious to know if it generates 100 or 1000 kg of downforce.
Also, if you know any site with this kind of info, please let me know

Thanks
See ya

[Guest]

Hey yeh i asked the same sort of question on the following site - http://fixtures.nzoom.com/motor/shellhe ... 21003.html where you will find

Q: How much downforce, (measured in Newtons or kgs isn't it?) would a modern F1 car produce with a typical wing level like that used in Barcelona? How would that compare to 1994 (Barcelona setup) before the FIA brought in rules to cut downforce?
James Forbes

Bob: A very difficult question to answer as the downforce levels on each car vary and they are one of the more closely guarded secrets in a team's war chest. In general terms a Formula 1 car travelling at 150 mph (240-ish km/h) will generate around 1600kgs of downforce. Enough technically to drive upside down in a long tunnel! The rules that were brought in to reduce downforce were immediately made irrelevant due to the advances made in aerodynamic design and efficiency using incredibly expensive and large wind tunnels with rolling roads. Whatever rules the engineers on the FIA can come up with, the highest paid and cleverest engineers in the world that work for the teams will find a way around those rules and find a way to exploit them. I cannot accurately answer the question of comparative aero packages from 1994 to now as so many parameters affecting those packages have changed.

[Monstrobolaxa]

In 2001 the figures were in the 1500 to 1700 kg of downforce......

I've heard that the distribuition of downforce is aproximatly:

35 - 40% - rear wing
25 - 30% - front wing
20 - 25% - diffuser
5 - 10% - body work (including flip ups.....etc)

[Monstrobolaxa]

slight corection....the front wing is between 25% and 35%

another note the downforce figures are maximum...note average.

[SuperSonic]

Obrigado, Monstro. (and guest too, whoever you are)

It's amazing how F1 cars can support all this pressure with a very short suspension travel.

Still about downforce, how the new rules (engine cover and rear wing) will affect the cars? Of course, the rear wing with 2 instead 3 elements will generate a little less downforce, but the bigger side parts of the rear wing and the bigger engine cover just don't make sense to me. Maybe the new engine cover affects the airflow to the rear wing, but we still have those strange side parts of the rear wing (100mm longer, right?)

Also, will never the FIA update its site with the new rules?

Amazing site and forum, congratulations.

sorry my poor english

See ya

Edit: I think the new rules were introduced just to show logotypes better

[Monstrobolaxa]

SuperSonic are you portuguese?

Well according to everyone the new engine covers are just for extra sposor areas and just for "showing off".....but the new engine cover also afects the air flow to the rear wing....so a slight loss might be felt....the 2 element rear wing for sure reduces the amount of downforce....but.....sooner or later they'll gain what they lost.....and some teams already have.

[SuperSonic]

Yes, for sure. Engines have more power, CoG is probably reduced, mass reduced, better gearboxes, better overall aerodynamics and, above all... tyres!!! I belive laptimes won't increase because of the new rules, except maybe in circuits like Monaco and Hungaroring.

Eu sou brasileiro

See ya

[Guest]

I've read that the diffuser creates close to half of the car's downforce.. any truth in that? Can't it not start forward of the rear axle line? Or something like that..

[SuperSonic]

1700kg * 20% = 340kg
So...

The diffuser starts at the rear wheel center line and go until a point 500mm behind it (don't know if it changed for 2004).

Well, I read that a car without wings (diffuser + bodywork) can generate its own mass in downforce...

35 - 40% - rear wing
25 - 35% - front wing
20 - 25% - diffuser
5 - 10% - body work (including flip ups.....etc)

Let's say 25% for diffuser and 10% for bodywork, total 35%.

35 -> 605
100 -> X

X=1728.57

Interesting.

See ya

[Monstrobolaxa]

No changes to the 2004 regs.....at least in this aspect...

The diffuser prior to 94 changes did produce around the number the guest mentioned.

[akbar21881]

3 years ago,in F1 racing.net,they have an article about downforce of F1 car.If I'm not mistaken,according to them,diffuser generate about 25% of the downforce,so is the front wing and the rest is generated by the rear wing.

But it doesn't make sense to me becoz its like having 75% of the downforce at the back.But it might be true if the aerodynamic centre(centre of pressure) is near the back of the car.How does the mass distribution interact with the downforce distribution??From equation of motion of the car,both longitudinally and laterally,both aero force and mass force present in the equation,an interact to each other in a complex coupled way.Can anyone explain in a simpler way?

[Reca]

“diffuser generate X%” in reality is “underfloor generate X%”, in the diffuser the static pressure growths to reach (ideally) the value of the freestream. It’s in the fore part of the underfloor that the static pressure is at minimum and in fact the centre of pressure (point of application of aerodynamic forces, isn’t the same as aerodynamic center) of the underfloor is quite forward in the car.
AFAIK the centre of pressure (of the vertical aero force) of the whole car is at about 40% of the length, so it should be in front of the cg. Anyway the centre of pressure moves longitudinally at different speed and pitch angles, it’s very important to reduce these variations to obtain a predictable behaviour of the car in different conditions.
The new rules about engine cover and endplate have probably an influence on the position of the centre of pressure for the lateral aero force, probably it moved a bit backward.

[pompelmo]

A F1 Car produces downforce that in speeds higher of 100km/h (60mph) the car will be on the track if turned around (on the "roof" of tunnel)

[seymour]

Here's an interesting link

I've posted it here, because the percentages are quite different from what has been quoted namely that the diffuser/underfloor does generate nearly half of the downforce.

As for actual downforce values, it definitely depends on the track, but if you look in this thread and scroll down a while, you'll find a famous pilot quoting a table from a Piola book that says 1700kgs at Monaco in 2000 at about 290km/hr. Interestingly they cite only 1500kgs at Monaco in 1999 which is a pretty remarkable increase year to year. I don't expect the same pace has been kept, but its reasonable to assume that teams will be generating quite a bit more downforce than that 4 years later.

You may also note in the same table that downforce generated at Monza is significantly less at a much higher speed.

I think the next major trick in aerodynamics that we will see--if we're not already seeing it and just not aware of it yet--is some sort of bodywork which at lower speed does not interfere with the primary downforce generating surfaces (rear wing, front wing, diffuser) but at higher speeds does in such a way that both downforce and drag are reduced allowing for faster straightline speed without compromising lower speed cornering.

Consider that the Enzo already does this with moveable aerodynamics surfaces. Could it be done without moveable surfaces?

[Reca]

A F1 Car produces downforce that in speeds higher of 100km/h (60mph) the car will be on the track if turned around (on the "roof" of tunnel)

More speed is required actually. Probably between 170 and 220 km/h, depending by the aero trim adopted, is the speed required to balance the weight... then a bit more speed is required to generate grip, without traction the trip on the roof would be quite short...

Consider that the Enzo already does this with moveable aerodynamics surfaces. Could it be done without moveable surfaces?

F1 bodywork parts aren’t movable in term of rigid degrees of freedom but they are very flexible (also without considering the rumours about the use of Shape Memory Alloy). Aeroelasticity (hence aeroelastic tailoring) is a well known discipline in F1. The trick is simply to have a deformation small enough to pass FIA tests, that anyway are limited to just few parts.