DOF_power

Front Wing Aerdynamics And Its Problem

12 posts in this topic

Front wing aerodynamics

The front wing of a Formula One car creates about 25% of the total cars downforce. Although this only occurs in ideal circumstances. When a preceding car runs less than 20m in front, the total downforce generated by the front wing may become as little as 30% of its normal downforce. Although this reduce of drag (because the air pressure is lower behind a car's rear wing), enables higher speeds at the end of straight, it significantly hinders the pursuing car in corners, as he cannot take these at normal speeds. This problem mostly occurs in fast corners, and is one of the most important reasons of the overtaking problem currently in Formula One. It is therefore a hard job to create a performing front wing, even more because disturbing the airflow too much will affect the rest of the car's aerodynamic efficiency too.

Regulations

3.4 Width ahead of the rear wheel centre line :

3.4.1 Bodywork width ahead of the rear wheel centre line must not exceed 1400mm.

3.4.2 In order to prevent tyre damage to other cars, the top and forward edges of the lateral extremities of any bodywork forward of the front wheels must be at least 10mm thick with a radius of at least 5mm.

3.7 Front bodywork height:

All bodywork situated forward of a point lying 330mm behind the front wheel centre line, and more than 250mm from the centre line of the car, must be no less than 100mm and no more than 300mm above the reference plane.

3.17.1 Bodywork may deflect no more than 5mm vertically when a 500N load is applied vertically to it 700mm forward of the front wheel centre line and 625mm from the car centre line. The load will be applied in a downward direction using a 50mm diameter ram and an adapter 300mm long and 150mm wide. Teams must supply the latter when such a test is deemed necessary.

Front wing design

A regular front aerofoil is made as a main plane running the whole width of the car (almost at least, limited by FIA regulations) suspended from the nose. Onto this are fitted one or more flaps which are the adjustable parts of the wing. On each end of the mainplane there are endplates. These make sure the airflow passes above and beneath the wing rather than around it. In recent years these endplates have played a crucial role in influencing the airflow around the front tyres, especially after the rule changes at the beginning of 1998 (wheelbase made smaller from 220cm to 180cm). These changes made front wing airflow interfere with the rotating airflow around the front wheels.

Article 3.17 has been introduced during 1998, after teams started experimenting with bending front and rear wings. When Ferrari introduced such a front wing at the end of 1997, it was produced in such a way that the wing would flex under aerodynamic loads. This means that as the speed increased, a force was produced that pushed the wing towards the ground. By means of a ground effect, this was particularly interesting for front wings because if would increase downforce at high speeds without an increase of drag. As rear wings began to fail and flew off during races, the FIA thought it was time to act and added 3.17 to the technical regulations of Formula One.

At the beginning of 2001, front wing regulations had changed in such a way, that the wing should be 100mm above the ground at least, instead of the 40mm until then. The FIA introduced this change to limit the cornering speeds of the cars. The idea was to decrease the ground effect that was generated by front wings close to the ground, working just like a diffuser.

Immediatley at the start of the season, Ferrari introduced a front wing that was bent down in the center line or the car. This new concept makes a handy use of a little hole in the regulations. The whole is the result of a rule, added in 1994, where the wooden bottom made it's entry. This wooden plate can be hung up as low as possible to the ground. As this plate is 50 cm wide, it was not foreseen that the front wing may be placed that low to the ground in 25cm at each side of the center of the car. Since the introduction by Ferrari, more and more teams have adopted the idea of curved front wings, with them also McLaren and Renault (see picture).

Though the reason that McLaren didn't make any of those changes until 2002, might have to do with the curve of the front wing before the change of regulations. It was namely curved up in the middle, so that the inner side was higher above the ground then both outer sides of the front wing. This type of wing is mostly useful on fast tracks where not much downforce is needed. It is there that airflow in the centre of the car can be more used by the diffuser in the back instead of lifting it up and create downforce in the front.

End plates

As some of the air that is needed to generate the front wing's downforce interferes with the rotating air around the front wheels, F1 teams have been developing the end plates from a simple plate to an integral part of the wing. To overcome the main problem of turbulence around the wheel, McLaren, and later Ferrari made in 1998 the inside edges of the front wing endplates curved to direct the air between both front wheels. One year after, all teams had adopted this technique to maintain front wing efficiency. Some other teams decided to decrease the width of the main plane just to the width between the front wheels. This left some room for extra wings and flaps, which caused the beginning of intensive end plate research. In 1998 changes were so radical that Ferrari produced six different designs of front wings throughout 1999, in order to reclaim the lost downforce by regulation changes.

frontwing2.gif

frontwing3.gif

AIRBOX PRODUCES MILD SUPERCHARGING

What the airbox achieves in modern Grand Prix cars is a mild supercharging effect, the tunnel from the intake rams air into the engine at a greater pressure than would otherwise be achieved. But the effect is not great enough only to make it necessary to have it.The airbox ensures that the engine is always supplied with sufficient non-turbulent air.The pressure in the airbox is measured constantly, as even the slightest pressure drop costs a lot of horsepower. If, for example, the driver’s sitting position is just a millimeter too high, this would lead to an unbelievable 20 HP less! However, not only do helmet aerodynamics have an impact on the airbox, but also factors like rearview mirrors, front airfoils and even the steering wheel position. That is why there are no real slipstream battles anymore! When the air behind a car is turbulent, the pursuer’s engine no longer obtains the required quantity of air to overtake another car. Apart from that, you also lose too much downforce from the airfoils.

Edited by DOF_Renault_BMW

Share this post


Link to post
Share on other sites

AIRBOX PRODUCES MILD SUPERCHARGING

What the airbox achieves in modern Grand Prix cars is a mild supercharging effect, the tunnel from the intake rams air into the engine at a greater pressure than would otherwise be achieved. But the effect is not great enough only to make it necessary to have it.The airbox ensures that the engine is always supplied with sufficient non-turbulent air.The pressure in the airbox is measured constantly, as even the slightest pressure drop costs a lot of horsepower. If, for example, the driver

Share this post


Link to post
Share on other sites
The airbox ensures that the engine is always supplied with sufficient non-turbulent air.

To create pressure higher than atmoshperic even in the best intake system the car must run very fast, so flow is turbulent.

The pressure in the airbox is measured constantly, as even the slightest pressure drop costs a lot of horsepower. If, for example, the driver

Share this post


Link to post
Share on other sites
That is why there are no real slipstream battles anymore! When the air behind a car is turbulent, the pursuer

Share this post


Link to post
Share on other sites

And then you'll see even more of Hamilton or others crashing (in race this time as opposed to practice) because he/they lost the front completely.

Building a car like this would help.

pa199210005_rain_.jpg

- pre 1993 slicks (18 inch the rear) and 2.0 meter width

- pre 1993 car height (the airbox and rear wing were high enough to be out of the turbulence)

- pre 1993 wings (bigger and lower in the front (= ground effect) and higher in the back (=clean air)) and diffuser (with more downforce generating grunt)

- pre 1994 active suspensions (witch puts down the big low front wing to get more ground effect downforce and stabilise the front)

- V10s

Edited by DOF_Renault_BMW

Share this post


Link to post
Share on other sites
To create pressure higher than atmoshperic even in the best intake system the car must run very fast, so flow is turbulent.

I would like to see some proof for that 20hp per milimeter...this bit looks really weird to me. as far as I know dynamic-charging intake systems are not that efficient. so this figure would make sense if it was something like +20 hp for whole system.

I think that dynamic-charging has minor meaning in case of slipstream battles. There are other things - mostly front wing loss of downforce while slipstreaming and massive turbulence created behind f1 car, then there are engine restrictions (modern f1 engines have very similar power levels + rev limiter). so after a corner the car in front is quite far away and this is major factor cause the one behind is too far to get inside a good slipstream straight away. even if he's faster out of the corner there's not enough straight line to get really close.

that's just my doubts - I may be wrong or I misunderstood some of that due to lack of technical english :D

Acording to atlasF1-autosport and other sources, the airbox shape, driver's height and helmet shape are all connected.

I was surprise to find that there are SAE papers with three-dimensional computational fluid dynamics (CFD) models of various airboxes geometries.

Power levels, as in peak/top end power yes, but on low and mid end there are still differences.

Share this post


Link to post
Share on other sites

As far as I know, the engine does not take a steady stream of air, it takes thousands of tiny sips. Therefore the best airbox would supply a continuous stream of pockets of turbulent air (spherical?) that flow smoothly through the airbox and into the ..... next bit. I don't know if there is an air filter on F1 cars, namely becuase it must be hard to get one to work efficiently at high intake speeds. You would've thought doing 50/60 laps of a clean circuit wouldn't present a major debris problem.

Now, back to my pot noodle. School holidays, love 'em :D

Share this post


Link to post
Share on other sites
Acording to atlasF1-autosport and other sources, the airbox shape, driver's height and helmet shape are all connected.

I was surprise to find that there are SAE papers with three-dimensional computational fluid dynamics (CFD) models of various airboxes geometries.

Power levels, as in peak/top end power yes, but on low and mid end there are still differences.

so newspaper and this article is written by a chap who isn't really engineer I guess.

As far as I know, the engine does not take a steady stream of air, it takes thousands of tiny sips. Therefore the best airbox would supply a continuous stream of pockets of turbulent air (spherical?) that flow smoothly through the airbox and into the ..... next bit. I don't know if there is an air filter on F1 cars, namely becuase it must be hard to get one to work efficiently at high intake speeds. You would've thought doing 50/60 laps of a clean circuit wouldn't present a major debris problem.

Now, back to my pot noodle. School holidays, love 'em :D

yes you could say that engine takes tiny sips, but it takes them itself. you don't have to blow into the engine cause it will suck air itself. and this sucking power is quite enormous really, so as I said before it's really hard to make a difference by blowing the air into the engine without use of mechanical charger. for example I've read report from research on those dynamic-charging intake systems and the best they came up with created 0.1 bar at almost 120 mph (in road going engine) which gave it few horsepower more.

so I guess if Shaquille O'neal was sitting in a f1 car and his helmet would be in front of the air vent, the engine would produce just a bit less horsepower at high speeds.

btw. I don't know for sure but I bet f1 engines all have air filters.

I saw few racing engines ruined cause they were runned for 1/4 mile without air filter...

Share this post


Link to post
Share on other sites

They do indeed have air filters, I watched an ITV documentary displaying various ones a few seasons ago, they were showing the bahrain one in particular, to stop all the sand getting in to the engine.

Share this post


Link to post
Share on other sites

Yes, F1 cars do have air filter/s. Imagine what would happen on a race track like Bahrain, where the sand is blowing continously.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now