[Official] Round 18 - Abu Dhabi Grand Prix

[Marbot]

Originally Posted by fourWheelDrift

I hate to argue but this is simply not so. Once you get over about 30mph aerodynamics dominates your cars fuel economy. Even on a road car efficiency at a steady speed is all about aero although of course acceleration is all about power to weight ratio but aerodynamics are massively important to road cars.

Disagree. Aero is far more important at 200 mph than it ever will be at 30 mph or 60 mph. Air resistance increases exponentially with speed. 30 mph to 60 mph is right at the bottom of the curve at where it really matters.

Originally Posted by fourWheelDrift

Remember to deal with the aero drag at 60mph requires 8 times the power you need at 30, at 90 that becomes 27 times the power.

Indeed. But, as you state, the power required to get from 30 to 60 mph is much smaller than is required to get from 60 to 90 mph. So aero benefits at a road cars AVERAGE speed (much much less than 60 mph, and lower than 30 mph in most cases) are negligible.

Not saying that aero isn't important to some degree, but drag coefficients on road cars haven't really been improved that much over the past 30 years or so. More time and money has been spent on making road car engines more efficient as opposed to making road cars more aerodynamic. A road car would have to look very different indeed to really gain from aerodynamics at the average speeds that most road cars go at. Hence why we still see lots of very unaerodynamic new cars on our roads. In fact, reducing the weight of a road car by as much as possible has more benefit. Aero comes well down the list of things that make road cars more efficient.

[JamesH]

I've been waiting for ages for someone to blame LH for SV's puncture and it hasn't yet happened. So I'm going to do it. That puncture could only have been caused by SV needing to stay ahead of LH in order to win the race. Hence it's LH fault, and he should be disqualified. And banned for the rest of this century. We CANNOT have this sort of behaviour on or off the track.

It's also extremely possible that LH uses his telekinetic ability to cause the tyre to come off the rim, which is, a we all know, against rule 24.5.1 "Drivers may not use psychic powers once the car is in Parc Ferme or during the race, unless they drive for Ferrari"

I rest my case.

[Marbot]

Originally Posted by JamesH

I've been waiting for ages for someone to blame LH for SV's puncture and it hasn't yet happened. So I'm going to do it. That puncture could only have been caused by SV needing to stay ahead of LH in order to win the race. Hence it's LH fault, and he should be disqualified. And banned for the rest of this century. We CANNOT have this sort of behaviour on or off the track.

It's also extremely possible that LH uses his telekinetic ability to cause the tyre to come off the rim, which is, a we all know, against rule 24.5.1 "Drivers may not use psychic powers once the car is in Parc Ferme or during the race, unless they drive for Ferrari"

I rest my case.

Maybe some people on German F1 forums might agree with that.

[JamesH]

Originally Posted by Marbot

Disagree. Aero is far more important at 200 mph than it ever will be at 30 mph or 60 mph. Air resistance increases exponentially with speed. 30 mph to 60 mph is right at the bottom of the curve at where it really matters.



Indeed. But, as you state, the power required to get from 30 to 60 mph is much smaller than is required to get from 60 to 90 mph. So aero benefits at a road cars AVERAGE speed (much much less than 60 mph, and lower than 30 mph in most cases) are negligible.

Not saying that aero isn't important to some degree, but drag coefficients on road cars haven't really been improved that much over the past 30 years or so. More time and money has been spent on making road car engines more efficient as opposed to making road cars more aerodynamic. A road car would have to look very different indeed to really gain from aerodynamics at the average speeds that most road cars go at. Hence why we still see lots of very unaerodynamic new cars on our roads. In fact, reducing the weight of a road car by as much as possible has more benefit. Aero comes well down the list of things that make road cars more efficient.

So what you are saying is that all those car manufactures really don't need to spend all that money on wind tunnel testing every new model?

[skells22]

That is the 1st time Vettel had to park it this year. and i knew his luck would run out one of these weekends.

[Adam43]

Originally Posted by Marbot

... Aero is far more important at 200 mph than it ever will be at 30 mph or 60 mph.
...

Well, I never...

[Paradise City]

Originally Posted by JamesH

I've been waiting for ages for someone to blame LH for SV's puncture and it hasn't yet happened. So I'm going to do it. That puncture could only have been caused by SV needing to stay ahead of LH in order to win the race. Hence it's LH fault, and he should be disqualified. And banned for the rest of this century. We CANNOT have this sort of behaviour on or off the track.

It's also extremely possible that LH uses his telekinetic ability to cause the tyre to come off the rim, which is, a we all know, against rule 24.5.1 "Drivers may not use psychic powers once the car is in Parc Ferme or during the race, unless they drive for Ferrari"

I rest my case.

I spotted a suspicious looking character in a McLaren outfit carrying a hunting rifle loitering around on the sandy knoll.

[Marbot]

Originally Posted by JamesH

So what you are saying is that all those car manufactures really don't need to spend all that money on wind tunnel testing every new model?

They don't spend that much on aero compared to other research and development efforts. The average drag coefficient of a road car as stayed at around 0.3 for around 30 or 40 years now. Manufacturers know that the average speed of the average road car in normal use is quite low, so aero isn't top of the list by a long way. Weight saving and engine development are far more important.

As a point of interest: The drag coefficient of a modern Ferrari 430 F1 is 0.34. The drag coefficient of a 1970 Citroen GS is 0.31, 1980 Renault 25, 0.28. 1990 Honda NSX, 0.32. Formula One car, between 0.7 and 1.1. Bearing in mind that lower figure = less drag.

[Marbot]

Originally Posted by Adam43

Well, I never...

It's true!

[fourWheelDrift]

Originally Posted by Marbot

Disagree. Aero is far more important at 200 mph than it ever will be at 30 mph or 60 mph. Air resistance increases exponentially with speed. 30 mph to 60 mph is right at the bottom of the curve at where it really matters.



Indeed. But, as you state, the power required to get from 30 to 60 mph is much smaller than is required to get from 60 to 90 mph. So aero benefits at a road cars AVERAGE speed (much much less than 60 mph, and lower than 30 mph in most cases) are negligible.

Not saying that aero isn't important to some degree, but drag coefficients on road cars haven't really been improved that much over the past 30 years or so. More time and money has been spent on making road car engines more efficient as opposed to making road cars more aerodynamic. A road car would have to look very different indeed to really gain from aerodynamics at the average speeds that most road cars go at. Hence why we still see lots of very unaerodynamic new cars on our roads. In fact, reducing the weight of a road car by as much as possible has more benefit. Aero comes well down the list of things that make road cars more efficient.

Perhaps I misunderstood you, my point is that the aerodynamic design is critical to the performance of a modern road car, which is true. Your point is that it is so well understood that development is now slow which is also true.

Incidentally because drag increases with the square of speed the average speed is a poor measure to use when assessing the importance of aerodynamics as time spent travelling higher than the average speed has a far greater effect on efficiency than time spent below the average. It is the same argument as measuring an alternating voltage, the most meaningful average is the Root Mean Square value not the arithmetic average becuase the energy transfer over a small time is proportional to the square of the voltage or in our case the drag is proportional to the square of the speed.

The speed at which Aerodynamics becomes dominant also depends on how much acceleration is in the driving cycle as this uses energy which is then dumped by the brakes. On the race track, where there is a constant pattern of acceleration and braking much of the energy provided by the engine is dumped into the brakes which is why aero is not dominant until you reach a higher speed. In a road car which normally has periods of cruise at part throttle aerodynamic effects become the dominant influence at much lower speeds than on the race track becuase the amount of energy you are dumping through the brakes is so much lower.

[ztnedman1]

Announcers said it appears that the puncture maybe was caused by the suspesion breaking first. Going off this theory anyone else think that the off Vettel had on the practice session may have been the reason? The car was never launched hard like it was for the race start.

Im thinking between the crash, launch, then riding curb after first corner he may have broke something and caused the puncture.

What a shame, would have liked to see him tie Schumacher for wins this season and win the DHL fastest lap but its not gonna happen now!

[Marbot]

Originally Posted by fourWheelDrift

Perhaps I misunderstood you, my point is that the aerodynamic design is critical to the performance of a modern road car, which is true.

No it is not, otherwise we wouldn't still be attaining the same cd figures that we were attaining 30 years ago for the average road car. In fact, the average drag coefficient figure has actually increased slightly (maybe there are too many 4x4s out there ?) !

As I have already shown above, there hasn't been much improvement in drag coefficient figures over the past 30 years.

An 84 Renault 25 has a better drag coefficient figure than most modern cars (0.28) and you certainly wouldn't think of that car as being particularly aerodynamic or stunning to look at.

It is more efficient use of time and money to make improvements in engine and weight saving technologies. Things like stop/start systems, diesel engine technology, petrol engine and and Hybrid technology, aluminium, carbon fibre, plastic body panels etc, all have a far more profound effect on road vehicle efficiency. And this seems to be born out in the real world.

A cars average speed is usually shown on the cars trip computer. Anyone showing more than 50 mph as an average is either spending a long time on motorways or needs their licence removing from them. Did you know that the average speed of a modern road driven Ferrari is less than 35 mph ? True!

Manufacturers know what these figures are and then ask themselves if it's really in their best interests to make all of their cars look like rugby balls when more fundamental ways of making their cars more efficient in the 'real world' are available.

[TrapezeArtist]

Originally Posted by Purist

TA, unless your drag-inducing surfaces are perfectly vertical, they will produce either lift or downforce, but this can also change with the pitch-up or pitch-down of the vehicle. Also, don't count on the cars only producing downforce when going forward. There are minimum requirements for how fast a car must be able to go at 90 and 180 degrees yaw before it can lift off.

Also, an aero-neutral vehicle would be unable to self-damp any natural reaction to a disturbance. If cars start fish-tailing and wiping out in the middle of straightaways because of this, the FIA might require huge run-off zones on either side of straightaways.

Without downforce, the cars would have to be completely redesigned because of the difference in loadings on every part of the car. Without the downforce, the current cars would be too stiff, and thus, so jittery as to be literally undriveable. They would simply react too violently to any disturbance for a human to possibly be able to keep the machine in line for very long.

With the newer breed of tracks, your plan won't work to shorten run-offs at corners either. Run-off might be made somewhat smaller at some fast corners. However, run-off size is determined by the terminal velocity achieved at the end of the straight. With minimal downforce, the long straights on newer tracks will be faster, because many of these straights are preceded by slow corners now, where it's mechanical grip that matter more anyway. Therefore, you'd be required to make the run-offs at those hairpins larger, NOT smaller. Also, if the approach to a fast corner is long enough for the terminal velocity on the straight before it to be higher than with the downforce, then that fast corner will be required to have more run-off as well.

You see, TrapezeArtist, it's NOT so simple a problem to solve.

I never said it was simple. It would require a total rethink and redesign, but is that such a bad thing?

I don't remember the exact words I used but I wasn't suggesting that there should be zero downforce at standard ride-height and rake (if that is what you mean by "aero-neutral"). There would have to be a small amount of downforce under those conditions in order to ensure that lift remained slightly negative under all conditions. That would be a matter of writing the rules in such a way that the designers could only extract a small amount of downforce.

The question of speeds and run-off and so on are quite complex. I think my own wet-finger analysis comes closer than yours, though a proper simulation would be needed to arrive at a real conclusion.

Anyway, we've got a race to discuss now.

[JeremySmith]

I am delighted to see that this thread has created such lively discussion about aerodynamic design...

[Marbot]

Originally Posted by JeremySmith

I am delighted to see that this thread has created such lively discussion about aerodynamic design...

In one of my posts, I did hint at moving it to another thread. Oh well.

I should point out that the 2014 regulations will go a long way to reducing drag (because they will only have 100 litres or so of fuel to burn as opposed to the limitless amount they now have), and therefore, downforce.

[TrapezeArtist]

Red Bull seem to be so touchy about Vettel's incident (hiding the work in the garage, and evasive answering of questions) that I doubt we will ever know the real cause. (Maybe no-one will ever know.)

The point that struck me was that the tyre was completely pushed off the bead by the time we got the head-on shot of Seb sliding across the run-off. That is not what I would expect from any puncture.

It seems to me to be much more likely that the tyre pulled off the bead under the cornering load. Possible causes:
Tyre not glued on properly. (I only just found out recently that they do glue them on.)
Manufacturing fault in the tyre.
Wheel rim or hump undersize.
Low tyre pressure.
Any others that I haven't thought of?

The flaw in this hypothesis is that the wheel and tyre had already done Q3 and the first corner. Unless low pressure was the cause, and the tyre started to come away in the first corner, and completed the move in the second corner.

[TrapezeArtist]

Great dice between Rosberg and Schumacher at the start of the race.

Did anyone else notice the BBC questioning the fact that Rosberg is only 5 points in front of Schumacher (before today)? As if that was a poor performance by Rosberg. Tells us more about where Schumacher is, I think.

[TrapezeArtist]

I am perplexed. Why did Di Resta not run in Q3 in order to save tyres, and then do a one-stop strategy for the race?

[JeremySmith]

Originally Posted by TrapezeArtist

Red Bull seem to be so touchy about Vettel's incident (hiding the work in the garage, and evasive answering of questions) that I doubt we will ever know the real cause. (Maybe no-one will ever know.)

The point that struck me was that the tyre was completely pushed off the bead by the time we got the head-on shot of Seb sliding across the run-off. That is not what I would expect from any puncture.

It seems to me to be much more likely that the tyre pulled off the bead under the cornering load. Possible causes:
Tyre not glued on properly. (I only just found out recently that they do glue them on.)
Manufacturing fault in the tyre.
Wheel rim or hump undersize.
Low tyre pressure.
Any others that I haven't thought of?

The flaw in this hypothesis is that the wheel and tyre had already done Q3 and the first corner. Unless low pressure was the cause, and the tyre started to come away in the first corner, and completed the move in the second corner.

Steve Matchett one of our Speed commentators thought that he might have lost the tyre under sheer acceleration ....

[Marbot]

Originally Posted by TrapezeArtist

I am perplexed. Why did Di Resta not run in Q3 in order to save tyres, and then do a one-stop strategy for the race?

There's always the chance that a one stopper could be switched to a two stopper. Then there's the chance of a puncture and also the reality that you probably wouldn't have got much further up the grid, anyway.

[Marbot]

Originally Posted by JeremySmith

Steve Matchett one of our Speed commentators thought that he might have lost the tyre under sheer acceleration ....

Would be very unusual, but he did get out of that first corner well ahead of Hamilton.

[JeremySmith]

I thought that as well although he knows his stuff...

Red Bull looked very glum which shocked me a little as they have pretty much won everything else...

[Born Racer]

Originally Posted by TrapezeArtist

Great dice between Rosberg and Schumacher at the start of the race.

Did anyone else notice the BBC questioning the fact that Rosberg is only 5 points in front of Schumacher (before today)? As if that was a poor performance by Rosberg. Tells us more about where Schumacher is, I think.

Whatever Rosberg does, he doesn't seem to get enough credit. On the BBC, I've also heard "why does Rosberg never go forward in races?" (answer: he's qualifying really well), and from Norbert Haug (a big Schumy fan and defender), "Michael has gone forward more than any other driver this season (a major reason: his qualifying has been disappointing). That's not me seeking to slate Schumy, but giving Rosberg some credit.

[Marbot]

Originally Posted by Born Racer

Whatever Rosberg does, he doesn't seem to get enough credit. On the BBC, I've also heard "why does Rosberg never go forward in races?" (answer: he's qualifying really well), and from Norbert Haug (a big Schumy fan and defender), "Michael has gone forward more than any other driver this season (a major reason: his qualifying has been disappointing). That's not me seeking to slate Schumy, but giving Rosberg some credit.

That's right. It's difficult to go forwards in a car that clearly hasn't got the legs of the top three when in race trim. But I would have thought that it might be easier to pass slower paced cars that you should have out-qualified and then had to out-race, in the first place.

Make no mistake, Rosberg is one of the drivers of the season, IMO.

[beau1]

Originally Posted by Born Racer

Whatever Rosberg does, he doesn't seem to get enough credit. On the BBC, I've also heard "why does Rosberg never go forward in races?" (answer: he's qualifying really well), and from Norbert Haug (a big Schumy fan and defender), "Michael has gone forward more than any other driver this season (a major reason: his qualifying has been disappointing). That's not me seeking to slate Schumy, but giving Rosberg some credit.

Rosberg got a huge amount of praise and reputation points last year...I think many people expected him to push on and show that it could be something special, which so far this year he hasn't done.
At the end of the day, if Schumacher's racecraft hadn't been so poor in a couple of races then he would be a good few points ahead. Rosberg not only goes backwards in some races but he's also mostly been outpaced by Schumacher since Monaco.