Audi LMP1 Discussion

[EverOne]

Maybe i'm wrong but i think the R18s will compete in Sebring next weekend are the same R18 last year with +15Kg penalty. I read it somewhere i don't remember.
Please, feel free to correct me

[chernaudi]

Final paragraph of this press release about the R18 e-tron quattro/Ultra:

http://www.fourtitude.com/news/publi...cle_7527.shtml

And this one that's the Sebring preview:

https://www.audi-mediaservices.com/p...tlichkeit.html

These confirm that the Sebring R18s are as for last year's specs except for 2012 diesel BoP changes and the 15kg BoP for lacking the fender holes. Similar BoP changes were also given to Pescarolo and Rebellion.

I hope that this helps.

[alexkiller8]

well i know that the three chassis that debuted at spa 2011 had a short life (the #1 (R18-104) and #3 (R18-105) gone destroyed at le mans, the #2 (R18-106) retired for museum). For sure two of three cars that will run at sebring will be the 2 r18 (R18-103 and R18-107) that ran in ILMC 2011 from imola race, the third one maybe will be built on a unused test chassis (101 or 102) or a new one where in future will be used for a ultras or e-tron quattro model.

[gwyllion]

I moved the discussion about diesel engines over here.

Originally Posted by alexkiller8

This year the only diesel engine running in WEC received a power and fueltank cut, so judging by that audi during LM week-end will decide if choice again an aggressive set-up (so around 580-600hp with stint of 8/9 laps i guess) or a more conservative one (550hp a stint of 9/10laps) or different strategies in each car because their four entries.

I do not agree with your estimates for laps per stint.

Last year, Peugeot did 12 lap stints and Audi 11 lap stints with a 65 liter fuel tank. See http://trussers.blogspot.com/2011/04...-times-at.html.
After the race Audi explained that they could not run the fuel tank dry. So they had a bit of diesel in the tank, but not enough to do a full lap.

11 * 60/65 = 10.15
12 * 60/65 = 11.08

Therefore, Audi will have no problem doing 10 lap stints. However, the 2012 engine will produce less power because of the restrictor and boost cut. The fuel consumption will probably go down a bit as well. So 11 lap stints should not be ruled out.

During the race, Audi can also use the hybrid system in their race strategy. It can be set up to improve the lap time, but also to save fuel.

[alexkiller8]

beyond the fact that audi stints in 2011 were sometimes 10laps and sometimes 11laps, my estimate were about if audi's choice to race with a comparable power output of last year (it means much more fuel consumaption with actual restrictors) with a -5l (and -7 in hybrid cars) in fuel tank, with these conditions i'm pretty sure that the car won't be able to run 10 laps.
About hybrid in lmp1 cars, right now we don't know if is a really usefull device to save fuel, for now it seems to be a good way to obtain a boost after slow points of a track.

About "the 2012 engine will produce less power because of the restrictor and boost cut" read some post above, it isn't necessary true, or not so dramatic as audi speaks about

[Dead-Eye]

Originally Posted by alexkiller8

well i know that the three chassis that debuted at spa 2011 had a short life (the #1 (R18-104) and #3 (R18-105) gone destroyed at le mans, the #2 (R18-106) retired for museum). For sure two of three cars that will run at sebring will be the 2 r18 (R18-103 and R18-107) that ran in ILMC 2011 from imola race, the third one maybe will be built on a unused test chassis (101 or 102) or a new one where in future will be used for a ultras or e-tron quattro model.

They likely had at least one spare tub after Le Mans that could be used for a new chassis.

[alexkiller8]

i'm sure that they had at least 2 spare/test tub unused in 2011

[gwyllion]

The chassis situation is clearly explained in http://www.mulsannescorner.com/newsmay11.html

Seven R18 chassis were built, two got destroyed in Le Mans and the winning car went to the museum. That means that Audi has four 2011 chassis to choose from for Sebring.

[gwyllion]

Originally Posted by alexkiller8

beyond the fact that audi stints in 2011 were sometimes 10laps and sometimes 11laps, my estimate were about if audi's choice to race with a comparable power output of last year (it means much more fuel consumaption with actual restrictors) with a -5l (and -7 in hybrid cars) in fuel tank, with these conditions i'm pretty sure that the car won't be able to run 10 laps.

Can you explain why they would need more fuel to produce the same power output? A less efficient combustion process because the engine is sucking in less air? Baretzky said that they improved the combustion process in the 2012 engine:

The target was to compensate for this as best as possible, for example through the re-engineering of the combustion process and the optimisation of the gas exchange – and we are extremely satisfied with the result. We also succeeded in making a significant weight reduction so that our 3.7 litre V6 TDI is now lighter than the 3.6 litre V8 TFSI of ten years ago – and this for approximately the same engine power, substantially more torque and considerably less fuel consumption.

Originally Posted by alexkiller8

About hybrid in lmp1 cars, right now we don't know if is a really usefull device to save fuel, for now it seems to be a good way to obtain a boost after slow points of a track.

They have to option to tune down the engine while the hybrid system is active. An extract from the RCE article about the Toyota TS030:

The system has three driver-controlled modes, adjusted by a rotary switch on the steering wheel. Mode A sets up the hybrid system (and one assumes the engine map) for maximum performance, giving the TS030 the ability to easily drop below 3m30 around the circuit at Le Mans, whilst mode C is set for maximum fuel saving, allowing the car to run longer stints. Mode B is a halfway house between both.

[alexkiller8]

Originally Posted by gwyllion

Can you explain why they would need more fuel to produce the same power output? A less efficient combustion process because the engine is sucking in less air?

if you read well, i said that there will be more fuel consumaption required IF they will want to obtain the same poweroutput of 2011 engine that had larger restrictor than actual one (even if the engine has been updated, however it will require air). It's simple to understand i guess, combustion is a reaction between fuel and oxidant (air). Indipendently by the restrictor size, the displacement available to fullfill remain the same but because of shorter restrictor size, the engine will get/suck less air than the amount of air that received in 2011! so to obtain the same power, the only other way is to compensate the lack of air with more fuel! i am not an engine tech or engineering but these concept are easy to understand.
If in 2011 audi used a certain "configuration A" (is just to give a name) on the engine to develope X hp with a Y restrictor size, is obiouvsly that in 2012 the "configuration A" will develope less X hp because the restrictor is shorter.

Take this example, a man is running with a mask on his mouth and nose, this mask has a little hole that let this man breath. Is sure that the man won't run easily and fast like when has his mouth and nose free because he breaths less air than usual, so in this situation the only way to go fast is to force and use more energy. Simple concept, well now he has a mask with a hole even more little, the only way to run like when he was wearing the previous mask is to force more and use more energy! different example but in theory it happens the same with engines.

I know that 2012 V6 3.7 engine will be better than the 2011 one, but to reach again that power around 600hp with 2012 restrictors the only way is to force, so use more fuel.

They have to option to tune down the engine while the hybrid system is active. An extract from the RCE article about the Toyota TS030:

sure i knew about this, but here again we all come back to previous matter, if a car has an aggressive set-up how much is usefull to tune down the engine while this is receiving a boost to be faster? as said a lot of times, it's all about a compromise between power and autonomy. A car that has an engine set to develope the max power output possible will have to pay something in autonomy and the reverse.... after all LM 2011 has been almost all about this (audi more powerfull but with less autonomy against peugeot less powerfull but with more autonomy). I didn't consider tyres because both cars had their best/worst moment about that during the race.

in bold the answer, however mine and yours are just speculations, we will see who was right in around 90 days

however just to be clearer about chassis situation:

R18-101 - never raced and unknown info about this, possibly a test and spare chassis

R18-102 - same of 101

R18-103 - chassis used for the #1 in imola, silverstone, road atlanta and zhuhai races in 2011 ILMC

R18-104 - chassis used for the #1 in spa and le mans, gone destroyed.

R18-105 - chassis used for the #3 in spa and le mans, gone destroyed.

R18-106 - chassis used for the #2 in spa and le mans, retired

R18-107 - chassis used for the #2 in imola, silverstone, road atlanta and zhuhai races in 2011 ILMC

[gwyllion]

Originally Posted by alexkiller8

iif you read well, i said that there will be more fuel consumaption required IF they will want to obtain the same poweroutput of 2011 engine that had larger restrictor than actual one (even if the engine has been updated, however it will require air). It's simple to understand i guess, combustion is a reaction between fuel and oxidant (air). Indipendently by the restrictor size, the displacement available to fullfill remain the same but because of shorter restrictor size, the engine will get/suck less air than the amount of air that received in 2011! so to obtain the same power, the only other way is to compensate the lack of air with more fuel! i am not an engine tech or engineering but these concept are easy to understand.

Have you every heard of air fuel ratio and stoichiometric mixture?

The amount of fuel that can be burned is proportional to the amount of air that is available in the combustion chamber. The following figure visualizes the situation for a petrol engine:

As you can see, there is a limit to the amount of fuel that can burned. The power goes down once the mixture becomes too rich!

Diesel engines, in contrast, run lean. If you approach the stoichiometric ratio, soot (black smoke) is formed because of an incomplete combustion.

Conclusion: burning more fuel does not necessarily increase power.

[alexkiller8]

Originally Posted by gwyllion

Have you every heard of air fuel ratio and stoichiometric mixture?

The amount of fuel that can be burned is proportional to the amount of air that is available in the combustion chamber. The following figure visualizes the situation for a petrol engine:

As you can see, there is a limit to the amount of fuel that can burned. The power goes down once the mixture becomes too rich!

Diesel engines, in contrast, run lean. If you approach the stoichiometric ratio, soot (black smoke) is formed because of an incomplete combustion.

Conclusion: burning more fuel does not necessarily increase power.

necessarily not, but as you wrote until this limit isn't reached, the power is increased.

[gwyllion]

Originally Posted by gwyllion

Diesel engines, in contrast, run lean. If you approach the stoichiometric ratio, soot (black smoke) is formed because of an incomplete combustion.

I managed to find a similar figure for diesel engines.

BSFC (purple) -> fuel consumption
BMEP (red) -> torque/power
particulate (black) -> smoke

Originally Posted by alexkiller8

necessarily not, but as you wrote until this limit isn't reached, the power is increased.

On the figure above you can see that the power keeps increasing until the smoke limit (around lambda 1.3) is reached. This phenomenon of diesel smoke is explained nicely in http://www.f1technical.net/forum/vie...143453#p143453.

In the past years, the diesels were already running very close to the smoke limit. It is impossible for Audi to increase the power any further by burning more diesel. The rules do not allow the cars to produce visible smoke. Although the ACO never probably enforced that rule. See http://www.racecar-engineering.com/a...s-all-illegal/.

[johnyardley]

Hi,

Reading Gwyllions F1 link it seems the injector hole size 0.2mm is the main factor to improving diesel engine performance. Perhaps in the future laser might be able to drill smaller hole?

Best wishes

John

[chernaudi]

If I may take this thread off the topic of fuel mileage vs power for a moment (which I'll get back to it in a moment), but it seems that the waters have gotten muddier as far as what Audi may've been doing at Road Atlanta--and that they probably intended for that to happen.

Because of (possible) WEC restrictions, there are actually very few ways that Audi can test at Sebring (teams can't test at a track less than 60 days before an event without FIA/ACO permission was at least a proposed if not an enacted testing restriction), it makes sense that Audi was testing the old cars at Road Atlanta. However, Audi didn't unload at Sebring until yesterday, though their transporters have been there since Thurs.

And who may've gone out and muddied the waters more? None other than Allan McNish, who posted a photo on his Twitter page of the Boeing "Dream Lifter" that delivered the WEC cars to Sebring. Could Allan just be pulling our chains? Probably, since Audi usually uses their own transport arrangements, though we're still far from certain what Audi were up to at RA, and when the e-tron and Ultra spec R18s will arrive at Sebring, or of they're already stateside, where they are. It may be a joke on Allan's part, but believe me, it may be useful cover for Audi Sport to make people wonder exactly what is where with the R18's now numerous variants.

Now back on the topic of fuel mileage vs power, with the diesels, there comes a point, like with gasoline engines where if you have too much raw fuel, it won't combust efficiently. Hence, you won't make any more power, and that potential energy of the raw fuel is largely unused and hence wasted. That happens shortly it seems after the diesels start to smoke in their case.

And it's also the same way with the air restrictors. That's why it never really paid to run a small engine under the rules, period, as revving and engine higher was no guarantee to increasing power after a certain point. Basically, once the air being sucked into the restrictors reaches well into the trans-sonic range to almost going supersonic, the engine won't make more power, either.

In other words, just burning more fuel is no guarantee after a point to make more power, and can result in fuel being burned for no gain and just being wasted pretty much, and the same can happen with trying to rum more RPM on an air-restricted engine won't increase power after a certain point. Both scenarios are basically an exercise in wasted energy for no performance gains.

[Aysedasi]

Originally Posted by chernaudi

If I may take this thread off the topic of fuel mileage vs power for a moment.....

Oh please do.......

Originally Posted by chernaudi

...(which I'll get back to it in a moment).

[chernaudi]

And Ayse, it got worse. I even looked up the Boeing 747 Dreamlifter. It makes this more of a joke on Allan's part because all Dreamlifters are still still owned by Boeing and are used by them mostly to deliver parts for the 787 Dreamliner. That's as far as I care to take this thread off topic, as this is a motorsports forum, not an aviation forum.

Still, though, Audi is a bit of master of using social media, and I wouldn't be surprised if the Tweets by Turner especially peeked Audi Sport's interest and they took this opportunity to throw more shadows on their RA activities. And of course, if Audi decided to use the FIA/ACO's rented cargo plane (probably an Airbus) to get their Sebring cars to Florida, it would be the older cars on there, to keep prying (non-Audi Sport) eyes away from their new items.

And if this is what was intended by Allan's photo posting, it may be working, because we still know jack and you-know-what about what happened at RA, and we have no whereabouts of the R18 e-tron quattro and Ultra cars, and probably won't until next week. Even if that's not the intent and McNish was just having some fun, it's still serving that purpose of deflecting any questions about what's where and leaving questions unanswered.

[Articus]

Is there really that much reading into a picture of a large airplane? Why does it matter what we know about where the E-Tron is? The one thing we do know is that they will have done 24 hour test before the 24 hours of lemans with the E-Tron. In that regard there are no secrets. its the same gameplan as last year. Test Test Test. We dont need a press release to tell us that.

The only thing i read into that RA test was that if it was possible that Audi may run the Petit Le Mans.

[gwyllion]

Originally Posted by chernaudi

Because of (possible) WEC restrictions, there are actually very few ways that Audi can test at Sebring (teams can't test at a track less than 60 days before an event without FIA/ACO permission was at least a proposed if not an enacted testing restriction), it makes sense that Audi was testing the old cars at Road Atlanta.

I have said this in the past. Read the rules before spreading inaccurate or incorrect information

The FIA WEC 2012 sporting regulations are available at http://private.fia.com/web/fia-publi...002%202012.pdf. You will want to read article 67.B which covers the restrictions regarding private testing.

Private tests must be announced to the FIA such that other competitors can join them. If you respect this rule, there are no restrictions on the date of the test.

The Promoter will inform all the competitors entered in the Championship of the place and date of these private tests and will communicate the contact details of the competitor who has reserved the circuit.
Competitors wishing to join in these tests may contact that competitor directly in order to take part.
No competitor is entitled to refuse the participation of another competitor in these private tests, unless the number of participants exceeds the maximum number of cars admitted to that circuit for private testing.

This could explain why Audi and Aston Martin both tested at Road Atlanta. Aston Martin reserved the track and Audi used the opportunity to join them, or the other way around.

Teams do have the option to keep the test exclusively private. These exclusive tests can not take place within 48 days of an official WEC event.

However, each competitor may, within the limit of 10 days of private testing per year, declare to the organiser an exclusive testing day which he will not share, nor transmit information to the other competitors.
In this case, the 30 days’ notice need not be observed.
Nevertheless, these tests cannot take place within the 48 clear days preceding a Championship Event on the same circuit as that Event.

[gwyllion]

Originally Posted by Articus

The only thing i read into that RA test was that if it was possible that Audi may run the Petit Le Mans.

That would be a logistical nightmare. There is only one week between the WEC 6 hours of Fuji (14/10/2012) and Petit Le Mans (20/10/2012).

[Dead-Eye]

Originally Posted by chernaudi

And Ayse, it got worse. I even looked up the Boeing 747 Dreamlifter. It makes this more of a joke on Allan's part because all Dreamlifters are still still owned by Boeing and are used by them mostly to deliver parts for the 787 Dreamliner. That's as far as I care to take this thread off topic, as this is a motorsports forum, not an aviation forum.

Still, though, Audi is a bit of master of using social media, and I wouldn't be surprised if the Tweets by Turner especially peeked Audi Sport's interest and they took this opportunity to throw more shadows on their RA activities. And of course, if Audi decided to use the FIA/ACO's rented cargo plane (probably an Airbus) to get their Sebring cars to Florida, it would be the older cars on there, to keep prying (non-Audi Sport) eyes away from their new items.

And if this is what was intended by Allan's photo posting, it may be working, because we still know jack and you-know-what about what happened at RA, and we have no whereabouts of the R18 e-tron quattro and Ultra cars, and probably won't until next week. Even if that's not the intent and McNish was just having some fun, it's still serving that purpose of deflecting any questions about what's where and leaving questions unanswered.

Are you serious? People sometimes joke on Twitter without being involved in conspiracies.

[MulsanneMike]

Originally Posted by gwyllion

That would be a logistical nightmare. There is only one week between the WEC 6 hours of Fuji (14/10/2012) and Petit Le Mans (20/10/2012).

Furthermore, what would be the point? There'd be no points to gain towards WEC and a lot to risk (equipment).

[chernaudi]

And social media strikes again--someone on Mulsanne's Corner's Facebook page asked about an alleged R18-related wreck at RA this week. To his credit, Mike has reported that he heard nothing of the nature from friends who live near the circuit, and they even took laptimes, with 1:09 being a common number.

Edit: A Barber School instructor said that one of the cars spun in turn 5 and caught a tire wall--the update didn't give any indication of how much damage was done. But I don't think that Audi will run PLM because of timing and that it means little to the WEC--no points to be scored and no real incentive for Audi to run other than claiming that they won PLM again.

And as to the rules on testing, Dagys said something of there being some limit of 60 days for some tests, that they can't take place within a time frame of less than 60 days. I don't know if that's now for the ALMS or not, but that's what he read and posted.

As for the McNish photo, when you consider that the Boeing Dreamlifter is owned by Boeing as a company transport (for 787 Dreamliner parts--like fuselages and wing sections and other things similar massive), it wasn't an ACO/FIA rented aircraft. I take it for granted that he was messing around, but Audi has been fairly cloak and dagger about their new cars, at least until the run at LM for the first time. Granted, they're no where near as bad as Peugeot has been known to be, but they on occasion have made it a pain to take certain photos of certain things until LM. I don't really think that Audi would take it that far, though I do wonder if Allan mis-ID'd the transport plane for the WEC cars

And as for the testing rules, I guess that there's no limit's really, and is sort of like the old boss is the same as the new boss. It seems that the actual "private" test days are limited to 10 days, but as long as the tests are open to anyone else who may want to run, there's no limit on testing. So for a team like Audi, not really much of a change, though I'll bet that they'll probably use up most of those days before Le Mans, including the 5 at Sebring.

[Articus]

Originally Posted by MulsanneMike

Furthermore, what would be the point? There'd be no points to gain towards WEC and a lot to risk (equipment).

Audi has 3 ultra's racing at Sebring. Add to that the 2 E-Trons for Le Mans and thats 5 cars plus last years cars and spares for this year. I dont beleive they are short on R18's. They would atleast run regular R18's with Champion or something in America. Audi Joest isnt the only team handles the R18's right?
In the same way the Toyota ramped up support for WEC is it beyond belief that Audi might do the same for Petit Le Mans? They have many drivers and many cars(If they are running 4 cars are Le Mans). The only constraint may be budget.

[MulsanneMike]

Originally Posted by Articus

Audi has 3 ultra's racing at Sebring. Add to that the 2 E-Trons for Le Mans and thats 5 cars plus last years cars and spares for this year. I dont beleive they are short on R18's. They would atleast run regular R18's with Champion or something in America. Audi Joest isnt the only team handles the R18's right?
In the same way the Toyota ramped up support for WEC is it beyond belief that Audi might do the same for Petit Le Mans? They have many drivers and many cars(If they are running 4 cars are Le Mans). The only constraint may be budget.

I'll reiterate, what would be the point except expenditure in the face of zero gain regarding WEC. Sure, they can do it, but Audi hasn't made any habit of doing something for nothing. I expect the car counts for PLM 2012 will be similar to a regular ALMS round and as such I've made no plans to attend this year; there's little reason to.