Red Bull top speed limit reason

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buffs
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Joined: 26 Sep 2011, 18:47

Red Bull top speed limit reason

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Does the Red Bull speed limit (to a value significantly lower than other teams top speed) have an aerodynamics reason (e.g. stall making unsafe the car, stress limits on airfoils, ...) or others?

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raymondu999
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Re: Red Bull top speed limit reason

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I assume you're talking about the car's low top speed.

What Red Bull have chosen to do is design a car with a lot of downforce; i.e. aerodynamic grip. But as with everything in life nothing is free. To do this, what happens is their car has a lot of drag (air resistance). So they get less top speed as a result.

That's the simple answer. Welcome to the forums :wink:
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munudeges
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Re: Red Bull top speed limit reason

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On the flip side the argument is that all Formula 1 cars have horrible drag coefficients no matter what you do, so the overriding factor in straight line performance to overcome that is still very much the engine.

At Monza Adrian Newey was asked the question about how they managed to do far better there than they had ever done before, despite not even getting anywhere near the top of the speed traps there either. Newey's first response did not involve drag:

"Renault have done a great job, along with Total developing the engine within the frozen regulations - oil and so forth......"

Draw your own conclusions.

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Sonic59
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Re: Red Bull top speed limit reason

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In fact its not their actual top speed limit. Its all about gear ratios and wing angle. It looks like their car works better in lower speeds, so they tried to get maximum advantage of that.
numbers don't lie

DaveW
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Re: Red Bull top speed limit reason

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As Sonic hinted, I suspect that RBR lack of top speed is an expression of their superior downforce (specifically, rear downforce).

On most tracks, gearing down to achieve greater acceleration from low speeds yields a better lap time even though that reduces (RPM limited) top speed - provided, of course, that the increased power can be transmitted through the tyres (which is where high rear downforce helps).

There are two issues. The increased drag of higher rear downforce, & what must be done to maintain aero balance. The performance of both RBR vehicles suggests that they achieve a superior L/D than the competition, & the difference in performance of the two cars suggests that one driver can cope better with a less than ideal aero balance (assuming that increasing front aero will increase drag overall or, perhaps, one driver has to run rather less rear downforce than the other for balance reasons).

In passing, I suspect that RBR also pays rather more attention to mechanical set-up than the competition.

Robbobnob
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Re: Red Bull top speed limit reason

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The real reason the Red Bull is slower than the other cars is there is more time to be made by accelerating fast and carrying higher corner speeds than having outright straight line speed, so the opt for the setup which maximises the gains in the breaking and accelerating zones, traction zones, sacrificing top end for ratios that compliment specific corners of the track
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raymondu999
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Re: Red Bull top speed limit reason

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Sonic brings up an interesting point. That the RBR is limited by gearing rather than drag. We know the RBR is the one that gears their cars shortest. They don't gain top speed by activating the DRS. They just gain acceleration. They do this so that they can still be in the effective power bands of the engine even in race mode. Could it be that actually, the RBR doesn't have the drag disadvantage it had in 2010? I think that's a very interesting point to be looked at.
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DaveW
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Re: Red Bull top speed limit reason

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Robbobnob wrote:The real reason the Red Bull is slower than the other cars is there is more time to be made by accelerating fast and carrying higher corner speeds than having outright straight line speed, so the opt for the setup which maximises the gains in the breaking and accelerating zones, traction zones, sacrificing top end for ratios that compliment specific corners of the track
You are absolutely correct... The problem is to explain why other teams have failed to arrive at the same result (bearing in mind that selecting gears optimized for a given track, tyres & engine is one of the easier simulation tasks - I think)
raymondu999 wrote:Sonic brings up an interesting point. That the RBR is limited by gearing rather than drag. We know the RBR is the one that gears their cars shortest. They don't gain top speed by activating the DRS. They just gain acceleration. They do this so that they can still be in the effective power bands of the engine even in race mode. Could it be that actually, the RBR doesn't have the drag disadvantage it had in 2010? I think that's a very interesting point to be looked at.
Apologies, I wasn't aware that RBR was reputed to have a drag disadvantage (or, at least, L/D disadvantage) in 2010, although the evidence did suggest that they had a huge downforce advantage (perhaps not quite the double claimed by LH). It is possible that the engine has a limited rev range, although it might also be that blowing "hot" makes the rear diffuser operate more efficiency.

The other interested fact to consider is MW consistent slow starts this year....

munudeges
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Re: Red Bull top speed limit reason

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You can talk about reducing drag as much as you want, but certainly on a circuit like Monza where straight line performance is the overriding factor it all comes back to the engine. If the Renault, as is believed, is lacking top-end power then it would make sense to keep the engine in the power bands where it is most effective most of the time rather than trying to drag out top end speed and letting the other aspects of straight line performance, like acceleration and traction, suffer.

DaveW
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Re: Red Bull top speed limit reason

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munudeges wrote:You can talk about reducing drag as much as you want, but certainly on a circuit like Monza where straight line performance is the overriding factor it all comes back to the engine. If the Renault, as is believed, is lacking top-end power then it would make sense to keep the engine in the power bands where it is most effective most of the time rather than trying to drag out top end speed and letting the other aspects of straight line performance, like acceleration and traction, suffer.
Again, I agree. But bearing in mind that the competition is capable of similar reasoning (presumably), why was the RBR so dominant.

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JohnsonsEvilTwin
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Re: Red Bull top speed limit reason

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Perhaps the Renault might have less BHP but a tad more torque.

Meaning it is more driveable.

This can also be backed up by the fuel consumption of the various engines. Renault requires less. More driveable engines will not work as hard as those of a peakier nature.
More could have been done.
David Purley

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raymondu999
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Re: Red Bull top speed limit reason

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I don't think more torque in itself would be more drivable. But a more constant torque curve would be more drivable - a flat torque curve maybe?
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Sonic59
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Re: Red Bull top speed limit reason

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JohnsonsEvilTwin wrote:Perhaps the Renault might have less BHP but a tad more torque.

Meaning it is more driveable.

This can also be backed up by the fuel consumption of the various engines. Renault requires less. More driveable engines will not work as hard as those of a peakier nature.
Torque and horse power are interconnected. Horsepower is an integrall of torque on RPM value. As soon as RPM is limited all u can do to increase max bhp is to change torque distribition on RPM. It looks like renault has more torque is lower RPM, and its a reason why renault engine is better in monaco/hungary and has more response.
numbers don't lie

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raymondu999
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Re: Red Bull top speed limit reason

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What JET means (I think) is that though the Renault might have less peak power output, the torque curve could be more progressive or flatter; and easier to drive.
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JohnsonsEvilTwin
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Re: Red Bull top speed limit reason

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raymondu999 wrote:I don't think more torque in itself would be more drivable. But a more constant torque curve would be more drivable - a flat torque curve maybe?
Thats what I mean :)
More could have been done.
David Purley