Adjustable Rear Wing (DRS)

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piast9
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Joined: 16 Mar 2010, 00:39

Re: Adjustable Rear Wing (DRS)

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csponton wrote:Image
I've calculated the time in which both of the cars would travel these 600m and the use of ARW would give the 0,145 s advance which is about 12 meters at 300km/h.

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747heavy
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Joined: 06 Jul 2010, 21:45

Re: Adjustable Rear Wing (DRS)

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the speed difference equals ~750 rpm, which the engine of the car using the DRS would need to rev higher or the equivalent in gear ratio difference (~0.26 in top gear).
Last edited by 747heavy on 05 Mar 2011, 17:46, edited 1 time in total.
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hollus
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Re: Adjustable Rear Wing (DRS)

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Everybody should have those 750rpm available in 7th gear, come the moment. That is, if they choose the track straight with the highest speeds as the activation zone.
That is the whole point of allowing the teams to use it in quali, IMHO. To take advantage of it in quali, they have to gear for it, so come the race, all cars are expected to be geared long enough to take advantage of the movable wing. If they were not allowed to use it in quali, they would probably set the longest gear for the maximum speed in quali instead of for a slipstream, and hit the limiter come the moment during the race.
As a side effect, if teams really gear long enough for this to work, slipstreaming should benefit in general. Last year there were many instances where cars slipstreamed only to stop accelerating in the very end, which I attribute to hitting the rev limit.
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marekk
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Joined: 12 Feb 2011, 00:29

Re: Adjustable Rear Wing (DRS)

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hollus wrote:Everybody should have those 750rpm available in 7th gear, come the moment. That is, if they choose the track straight with the highest speeds as the activation zone.
That is the whole point of allowing the teams to use it in quali, IMHO. To take advantage of it in quali, they have to gear for it, so come the race, all cars are expected to be geared long enough to take advantage of the movable wing. If they were not allowed to use it in quali, they would probably set the longest gear for the maximum speed in quali instead of for a slipstream, and hit the limiter come the moment during the race.
As a side effect, if teams really gear long enough for this to work, slipstreaming should benefit in general. Last year there were many instances where cars slipstreamed only to stop accelerating in the very end, which I attribute to hitting the rev limit.
Not quite sure about this.
You gain max speed, but you loose acceleration compared to "normal" gear ratios. 600m seems to be on the edge, i believe they'll need more then that for DRS to help in overtaking.

timbo
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Joined: 22 Oct 2007, 10:14

Re: Adjustable Rear Wing (DRS)

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marekk wrote:You gain max speed, but you loose acceleration compared to "normal" gear ratios.
No.
You gain top speed due to lower resistance which also gives higher acceleration.

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747heavy
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Joined: 06 Jul 2010, 21:45

Re: Adjustable Rear Wing (DRS)

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I think, it will depend on "what is defining our terminal speed/topspeed" drag or the rpm limit of the engine.
If we assume (for a moment), that the car is geared to reach it´s topspeed at the end of the longest straight while just reaching the rpm-limiter, the same car with less drag (DRS activated) would reach it´s topspeed earlier on the straight, means would travel for longer at the a higher speed, but can´t reach a higher absolute topspeed due to the rpm limit. - IMHO

It would close onto the car in front, because it is traveling faster for longer.
Anyhow, the posted data from cponton, indicating a higher terminal speed of the car with the DRS activated, would imply that the car is geared "too long" under normal drag conditions, not reaching it´s max. rpm at the end of the straight.
It would suffer twice, being geared "too long" would mean compromised acceleration early on, as long as it is not grip/traction limited anyway.
The question is, where is the crossover point, between traction limited and power/drag limited.

An interesting consideration in this context, are the new Pirelli tires.
By the look of it atm, the cars will be increased traction limited due to tire wear, even offsetting the reduction in overall weigth fom the burned fuel.

So good traction/powerdown early on will be very critical - IMHO
If you can´t get the power down early on, you wont reach your terminal speed/rpm-limited or do so later (from lap to lap).

The gear strategy to use is maybe not as straight forward as it seems, also keeping changed weather conditions (windspeed and direction etc.), as well as tire degration in mind.
"Make the suspension adjustable and they will adjust it wrong ......
look what they can do to a carburetor in just a few moments of stupidity with a screwdriver."
- Colin Chapman

“Simplicity is the ultimate sophistication.” - Leonardo da Vinci

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hollus
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Re: Adjustable Rear Wing (DRS)

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Gearing should be done mostly with quali in mind. In quali you can use the adjustable wing in many places: in every straight, and in not grip limited corners, meaning the car spends much more time at higher speeds all around the circuit.
One can gear the car (not only 7th) for this magic lap and suffer lower acceleration all race, or gear for the race, largely done with heavy fuel loads, partly on worn tires and mostly without the adjustable wing.
I guess it will depend on how efficient the wing proves to be for overtaking, but I see little point in gearing for the race if that leads to qualifying 5 positions lower.
It sure will make for some interesting gambling. How do you gear on saturday when a wet race is predicted on sunday???
Rivals, not enemies.

marekk
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Joined: 12 Feb 2011, 00:29

Re: Adjustable Rear Wing (DRS)

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hollus wrote:Gearing should be done mostly with quali in mind. In quali you can use the adjustable wing in many places: in every straight, and in not grip limited corners, meaning the car spends much more time at higher speeds all around the circuit.
One can gear the car (not only 7th) for this magic lap and suffer lower acceleration all race, or gear for the race, largely done with heavy fuel loads, partly on worn tires and mostly without the adjustable wing.
I guess it will depend on how efficient the wing proves to be for overtaking, but I see little point in gearing for the race if that leads to qualifying 5 positions lower.
It sure will make for some interesting gambling. How do you gear on saturday when a wet race is predicted on sunday???
Last few years, with very durable and predictable bridgestone tyres, it was all about track position.
This year looks as it will be all about optimizing tyres. Even 5 places back on the grid are not that important, if you manage to do few quick laps more than competition.
We observed already very slow actuation rate of RedBull's DRS - maybe it's tyre saving in action ?

timbo
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Joined: 22 Oct 2007, 10:14

Re: Adjustable Rear Wing (DRS)

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I had this idea from looking at the new Ferrari RW.
Maybe I'm wrong with this, so I would like to discuss.
Do you think it can be beneficial to sacrifice some of ARW drag reduction effect to retain a bit more DF and have better stability, which in effect would allow to use ARW in fast corners?
Maybe we would see track-dependent ARW setup?

hud
hud
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Joined: 04 Nov 2010, 08:38

Re: Adjustable Rear Wing (DRS)

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hollus wrote:
.......

It sure will make for some interesting gambling. How do you gear on saturday when a wet race is predicted on sunday???
Did they choose gear ratio on saturday? i thought the ratios is to be compromise to suit at least 5 tracks as the gearbox has to last for 5 consecutive race weekends. So, whether it's raining or not it shouldn't be an issue.

or... i misunderstood the gearbox rules.
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Giblet
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Re: Adjustable Rear Wing (DRS)

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timbo wrote:I had this idea from looking at the new Ferrari RW.
Maybe I'm wrong with this, so I would like to discuss.
Do you think it can be beneficial to sacrifice some of ARW drag reduction effect to retain a bit more DF and have better stability, which in effect would allow to use ARW in fast corners?
Maybe we would see track-dependent ARW setup?
Is this purely a hypothetical question? The ARW is only allowed on one straight per track and only within 1 second of a car in front.
Before I do anything I ask myself “Would an idiot do that?” And if the answer is yes, I do not do that thing. - Dwight Schrute

hud
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Joined: 04 Nov 2010, 08:38

Re: Adjustable Rear Wing (DRS)

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i assume he's talking about benefit in qualifying pace.right timbo?
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timbo
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Joined: 22 Oct 2007, 10:14

Re: Adjustable Rear Wing (DRS)

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hud wrote:i assume he's talking about benefit in qualifying pace.right timbo?
Yes.
That would mean sacrificing some overtaking ability for better qualifying performance.

volarchico
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Joined: 26 Feb 2010, 07:27

Re: Adjustable Rear Wing (DRS)

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It seems from recent pictures that a lot of teams are going for small chord second element wings...so maybe they are focused on using them throughout qualifying and not as much at the race?

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horse
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Joined: 23 Oct 2009, 17:53
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Re: Adjustable Rear Wing (DRS)

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timbo wrote:Do you think it can be beneficial to sacrifice some of ARW drag reduction effect to retain a bit more DF and have better stability, which in effect would allow to use ARW in fast corners?
I'm not quite sure I get the logic of what you are saying? Put more downforce on the car so that you don't need to use the flap at all? Then why bother with the flap? Or are you talking about trimming the flap, or not allowing it to open fully so you have a "half downforce" mode?

Something like the half downforce mode could possibly be useful for the right track, but you'd want to be able to get it working fully for the race again. You'd look a bit silly when an ARW/KERS attack makes you looks like you're standing still but then you can't get them back because your own ARW is deficient.
volarchico wrote:It seems from recent pictures that a lot of teams are going for small chord second element wings...so maybe they are focused on using them throughout qualifying and not as much at the race?
I was thinking that this sort of element might have better aerodynamic properties when open, as there is not as much camber. The larger flaps with higher camber may have been stalling a bit (in a bad way) when in the open position.
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