Dirty air sensitivity and regulations

[bhall II]

I think a fan probably is one of most resistant devices to create DF in turbulent air, and does not cause any dramatic change on the aerodinamic parts behind it as it does not change anything phisically like active wings would do

You don't think pointing two fans straight up into the air from the front of the car will have any effects downstream?

Moreover, it's possible that adding weight to the extremities of a car will negatively impact tire wear/degradation in much the same way as the understeer that occurs when driving within a another car's turbulent wake. But, you'd need to ask someone who has a better grasp of vehicle dynamics, because I know jack --- about it.

[SectorOne]

It sure don´t help having tires that destroy themselves immediately when they start sliding a bit.
With a Bridgestone tire you could at least have a longer go at getting past someone while in the Pirelli era you effectively add another stop to your strategy if you don´t pull back and nurse the tires.

[trinidefender]

Here is something that people can get data for and analyse when it comes to across grid downforce reduction levels (through seasonal regulation changes) and overtaking numbers. The best race to look at on the calendar so far would be Mexico, followed a long way by Brazil.

It was reported that through larger outlets and increased cooling packages to keep the cars cool in the thinner air and reduced downforce levels also from the less dense air that downforce decreased by 25-30% if I remember correctly.

Go forth and have fun looking at overtakes in that race, lap times etc. I seem to remember Checo and Jensen pulling off a few decent overtakes there.

[zac510]

We can talk all we want about fan cars, active aero, drum brakes, wooden tyres, impossible to drive cars etc etc. But ultimately if you want close battles you need cars hitting the same laptime but in different ways.

The homogenisation of tracks by adding chicanes that started around the late 90s has not helped this as it meant that car designs converged to suit the most common track type.

Admittedly in the last few years we've had a couple of tracks that are either slow (Singapore) or fast (A1 ring's return, Baku) so perhaps F1 is trying to address this.
To give one example, the loss of a track like the 80s-90s Hockenheim took away an opportunity for a car with low drag and a stout engine like Williams-BMW did a few times.

One thing is for sure from this thread is that there is no smoking gun to change this characteristic of F1 - if a smoking gun could actually even cut through the politics of F1! However there seems to be a lot of small iterative changes that can potentially be made.

[turbof1]

Here is something that people can get data for and analyse when it comes to across grid downforce reduction levels (through seasonal regulation changes) and overtaking numbers. The best race to look at on the calendar so far would be Mexico, followed a long way by Brazil.

It was reported that through larger outlets and increased cooling packages to keep the cars cool in the thinner air and reduced downforce levels also from the less dense air that downforce decreased by 25-30% if I remember correctly.

Go forth and have fun looking at overtakes in that race, lap times etc. I seem to remember Checo and Jensen pulling off a few decent overtakes there.

Yes of course, but it's not the same as regulatory-wise reducing downforce. What you have in Mexico is making each and every aero device of the car more aero neutral. If the theoritically the car ran in a vacuum, it would be generating zero downforce (aside the fuss of the driver suffocating and the engine not starting at all, but whatever).

However, regulation changes up until now were nowhere close to such an evenly reduction in downforce. Usually the FIA would point to a specific part and reduce it's angle or size, neglecting what the effect would be in the complete aero system of the car i.e. removal of the beam wing causing reduced turbulent to be directly send into the path of the trailling car, causing it to loose downforce a lot even though turbulent airflow is reduced.

My personal opinion on the matter is that these cars handle turbulent airflow that poorly, that if you increase downforce with specific attention paid to getting turbulent airflow out of the path of the trailling car, you would have a better situation then we have currently.

I am neither necessary supporting to increase downforce through placing a fan. It ran exactly one race, so we do not know the first thing about the implications. It sounds nice on paper from the armchair, but a fan will not stop a car from producing turbulent airflow a trailling car has to deal with (and a fan would increase the mass flow immensily, leading to a big increase in turbulent flow as well). In my view you'd have to pretty much standarize the car to make it work because even if a fan can overcome turbulent flow, you can't have other aero devices which are not powered by a fan as these will be subject as well to the mass turbulent flow.

[Andres125sx]

I think a fan probably is one of most resistant devices to create DF in turbulent air, and does not cause any dramatic change on the aerodinamic parts behind it as it does not change anything phisically like active wings would do

You don't think pointing two fans straight up into the air from the front of the car will have any effects downstream?

They don´t need to point straight up into the air, firstly they don´t need to be plural, and they could point sideways for example. Or it could even be channeled to the less sensible part of the car

Moreover, it's possible that adding weight to the extremities of a car will negatively impact tire wear/degradation in much the same way as the understeer that occurs when driving within a another car's turbulent wake.

Or it could balance the car, as currently weight distribution is not perfect 50-50, but around 45-55. Anycase a small fan only for the front wing would be very small and light, but as stated, it does not even need to be placed on the nose of the car. A vacuum cleaner motor is not in the suction point but in the main body, a simple channel will solve it, and that´s supposing it really is a problem

[Andres125sx]

even if a fan can overcome turbulent flow, you can't have other aero devices which are not powered by a fan as these will be subject as well to the mass turbulent flow.

True, even if the fan is not affected by dirty air the rear part of the car will be

What if the fan is placed behind the FW, down the nose, pointing directly behind, to the T-tray and floor?

Like blown diffusers, but for the whole floor. Maybe this way it could also help the devices wich are not powered by a fan to create DF. Probably not as effectively as the FW so DF will still be limited by the rear end, but it might improve rear DF too?

[turbof1]

even if a fan can overcome turbulent flow, you can't have other aero devices which are not powered by a fan as these will be subject as well to the mass turbulent flow.

True, even if the fan is not affected by dirty air the rear part of the car will be

What if the fan is placed behind the FW, down the nose, pointing directly behind, to the T-tray and floor?

Like blown diffusers, but for the whole floor. Maybe this way it could also help the devices wich are not powered by a fan to create DF. Probably not as effectively as the FW so DF will still be limited by the rear end, but it might improve rear DF too?

Then you have a heavily forward biased downforce, which is useless. The fan is placed at the back because it's from there it can drive the whole downforce coming across the floor, generated the downforce across the whole car.

Edit: in all honesty the more I think about it, the more I feel it would actually be a disaster. I mean when you have this in front of you:



You know your aerodynamics will have a problem. That propellor will probably make it difficult even for the trailling driver to breathe and cool his car properly, let alone having processing the mass turbulent to underneath the car.

I think it can be done much more sensible. I'm currently looking for overtaking number for super formula, which have superior downforce compared to F1. I'll get back to this.

[bhall II]

They don´t need...

1. It doesn't matter where a fan is vented; it's going to increase the size and effect of the car's wake.
2. Weight distribution is virtually standardized by the regulations and has been since Pirelli entered the sport.

4.2 Weight distribution :
The weight applied on the front and rear wheels must not be less than 319kg and 376kg respectively at all times during the qualifying practice session.
If, when required for checking, a car is not already fitted with dry-weather tyres, it will be weighed on a set of dry-weather tyres selected by the FIA technical delegate.

The rule exists to be a handicap that increases overtaking. Frankly, I think eliminating it would solve A LOT of problems on its own.

[Andres125sx]

even if a fan can overcome turbulent flow, you can't have other aero devices which are not powered by a fan as these will be subject as well to the mass turbulent flow.

True, even if the fan is not affected by dirty air the rear part of the car will be

What if the fan is placed behind the FW, down the nose, pointing directly behind, to the T-tray and floor?

Like blown diffusers, but for the whole floor. Maybe this way it could also help the devices wich are not powered by a fan to create DF. Probably not as effectively as the FW so DF will still be limited by the rear end, but it might improve rear DF too?

Then you have a heavily forward biased downforce, which is useless.

No, that´s not how the idea would work

If posible, I still think it might be a good option to adjust DF levels when in a slipstream, total DF of the car would be determined by the floor and rear wing (restricted by rules to achieve desired levels) , while the FW would only be tool to keep the car balanced constantly, even if in a slipstream.

Edit: in all honesty the more I think about it, the more I feel it would actually be a disaster. I mean when you have this in front of you:

http://en.espnf1.com/PICTURES/CMS/8200/8228.jpg

You know your aerodynamics will have a problem. That propellor will probably make it difficult even for the trailling driver to breathe and cool his car properly, let alone having processing the mass turbulent to underneath the car.

But the fan would be far smaller as it only would be for the front wing instead of the whole car, so the volume of air will not be comparable to that pic.

And I don´t think any driver complained in the past about difficulty to breathe, not even with that big fan. Did they?

I think it can be done much more sensible. I'm currently looking for overtaking number for super formula, which have superior downforce compared to F1. I'll get back to this.

And I´ll be looking forward that read

[Andres125sx]

They don´t need...

1. It doesn't matter where a fan is vented; it's going to increase the size and effect of the car's wake.

Let´s imagine it´s channeled through the RW endplates so the air exit is at the highest point of the car, facing up... would that still affect the trailing car?

It might even help with rear DF, similar to the beam wing, depending on the exact location and orientation of the exit

2. Weight distribution is virtually standardized by the regulations and has been since Pirelli entered the sport.

4.2 Weight distribution :
The weight applied on the front and rear wheels must not be less than 319kg and 376kg respectively at all times during the qualifying practice session.
If, when required for checking, a car is not already fitted with dry-weather tyres, it will be weighed on a set of dry-weather tyres selected by the FIA technical delegate.

The rule exists to be a handicap that increases overtaking. Frankly, I think eliminating it would solve A LOT of problems on its own.

May you elaborate? I don´t understand how a weight distribution restriction can be a handicap intended to increase overtaking.

[bhall II]

1. Yes, it would impact the trailing car. But, the effects in any case are difficult to conceptualize, especially if air flow is vented from a fan at a different velocity than surrounding air flow, as it would create very unusual vortices.

2. I think the general idea is to prevent teams from truly figuring out the tires, i.e. no one is allowed to master "the cliff." I'm not especially well-versed in vehicle dynamics, though. We need someone else for that.

Let's see if the quote notification feature can be used to summon a brighter mind...

I enjoy wearing ladies undergarments. It makes me feel complete.

What effect does weight distribution have on tire wear/degradation? How does 4.2 - de facto standard weight distribution - affect competition?

[Tim.Wright]

Let's see if the quote notification feature can be used to summon a brighter mind...
Also I luv willies

Mass distribution is a fundamental parameter in practically every aspect of handling inluding grip, balance and degredation. I don't mean this in a handwaving preachy kind of way but rather objectively - if you open any book on vehicle dynamics, ALL of the main governing equations are written in terms of mass, mass distribution, cornering stiffness and velocity.

Degradation is another thing, also fundamentally affected by mass distribution because deg is affected by the thermal history and this primarily depends on axle mass and axle side slip.

Though I don't really agree it was introduced as an equalisation measure. If I remember correct, the mass distribution rule was added for the first year of the Pirelli tyres because at the time no-one, not even Pirelli, would have had sufficient data to choose an optimised mass distribution. It would have literally been monkeys throwing darts.

Had the mass distribution been left open it would have been pot luck as to who nailed it and they would have likely run away with the championship whereas those who guessed wrong would have been stuck at the back with no possibility to improve without fundamentally redesigning the whole car.

The cynic in me thinks it was an agenda likely pushed by the big teams who's shareholders didn't like the idea of such a fundamental parameter being indeterminate (i.e. they couldn't simply thow money at the problem to solve it).

[bhall II]

I agree that the rule was introduced to normalize the impact of the tires during Pirelli's first year. It was only supposed to apply for one season, but it's been included in the regulations ever since (save for 2014), ergo my belief that the rule is now used to keep things "interesting."



Just an opinion, though. (And thanks for the input.)

The homogenisation of tracks by adding chicanes that started around the late 90s has not helped this as it meant that car designs converged to suit the most common track type.

Those characteristics also require wings to be set at higher angles of attack than would otherwise be necessary in order to stabilize the car during heavy braking.

[Andres125sx]

1. Yes, it would impact the trailing car. But, the effects in any case are difficult to conceptualize, especially if air flow is vented from a fan at a different velocity than surrounding air flow, as it would create very unusual vortices.

That was not a problem with EBDs, any reason they would be with a fan?

And obviously there would be some impact on the trailing car even if the air exits are at the highest point of the car, but what I was really asking is if it would be a deeper impact than currently with current FWs

Don´t you think current FW cause more problems to the trailing car than it´d cause a FW using a fan with the air exit at the RW facing up? Obviously it will never be inocuous to the trailing car, but causing dirty air at the same height the trailing car should be more harmful than causing dirty air at a higher height than the trailing car, shouldn´t it?