Audi LMP1 Discussion

[Mal]

Originally Posted by chernaudi

The e-turbo didn't have any issues, nor was it intended to be part of a hybrid system. Audi were going to use it only for anti-lag, where it showed no advantage over the VTG turbo they already had.

For '15, I'd have to say that it's almost certain that it'll be part of a hybrid system, be it with a more powerful flywheel or a flywheel supplemented by a smaller battery or supercap system. Audi have already tested a 4MJ and a 6MJ system in private testing, possibly also at the Michelin tire test in Estoril.

I was always cynical about the explanation Audi gave at the time.

[MyNameIsNigel]

Originally Posted by gwyllion

Ullrich is fairly pessimistic about 2015

source: http://www.dailysportscar.com/2014/1...-and-2015.html

I find this part a bit intriguing:

"At present there is no prospect of a change in the balance between the various solutions but there is always the possibility of a change when you homologate a new car."

[Deleted]

What defines a 'new car'... I mean technically today the factories are pushing out new cars every year. But when it's not a relatively big step like 2011 R18 TDI to 2012 hybrid or even more obviously 2013 old regs R18 to 2014 fuel flow R18, but rather just "an evolution" like 2012 to 2013 or indeed 2014 to 2015, does that classify it as new car? How is this defined?

If every LMP1(-factory) 'evolution' has a chance to be classified as new car and therefore get the 'solution' re-balanced by the EoT upon homologation, what's the point of having "once-a-year-BoP-change-after-LM" written into the rules if it's not necessarily even followed?

[MyNameIsNigel]

Be it an evolution or a revolution, I would expect that an homologation is necessary before any "new car" is allowed to race, and that this homologation is basically valid for the whole season.

I don't believe that the homologation of a new car has any bearing on the EoT as such, the EoT being specifically reviewed each year after LM, i.e. long after the cars have been duly homologated. I therefore struggle to understand what Dr. Ullrich is apparently suggesting by his statement.

As Audi are likely going to have to introduce as second ERS and switch to a higher ERS class (4MJ or 6MJ at best), this should imply that the 2015 car will necessarily have to go through a new homologation process. I suspect that the same holds true for Toyota and Porsche if they opt to switch to the 8MJ ERS class.

[MyNameIsNigel]

Looking at the various options available to Audi to improve performance for next year, the "e-turbo" solution trialled by Audi last winter looks to be one of the most logical evolutions.

But what is the "e-turbo" solution supposed to look like ?

In the original press release issued on December 12th, 2013, the solution was described as follows:

Hybrid system with an electric turbocharger in the internal combustion engine (ERS-H – Energy Recovery System Heat, a system that stores energy converted from heat)
(…)
In addition to the internal combustion engine, the powertrain concept, for the first time, features the integration of two hybrid systems. As in the past, a Motor-Generator-Unit (MGU), during braking events, recovers kinetic energy at the front axle, which flows into a flywheel energy storage system. For the first time, the turbocharger of the internal combustion engine is linked to an electrical machine, which makes it possible to convert the thermal energy of the exhaust gas flow into electric energy – for instance when the boost pressure limit has been reached. This energy also flows into the flywheel energy storage system. When the car accelerates, the stored energy can either flow back to the MGU at the front axle or to the innovative electric turbocharger, depending on the operating strategy.

As we know, Audi ultimately shelved this solution which did not make it to the actual race car.

It was subsequently claimed by Audi representatives that the e-turbo solution was not intended to be used to recover energy, but mainly as anti-lag system, which statement is in evident contradiction with the original statements in the press release of December 2013. If the electric turbocharger is not supposed to recover energy from the exhaust gases, then why describe it as an ERS-H ? Which statement is true then ?

There is at least concrete evidence that may support the most recent statement, namely the solution embodied in the form of the Audi RS5 TDI Concept that was presented last June (which presentation was interestingly coinciding with the LM event…).

The engine of the Audi RS5 TDI Concept is equipped with a small electric turbocharger that is used to supplement a conventional turbocharger at low revs in order to reduce turbo-lag. As shown in the following illustration, the electric turbocharger is located in a bypass downstream of the charge air intercooler, i.e. at a location where the e-turbo is unlikely to be much of a benefit in term of energy recovery from the exhaust gases :


This small electric turbocharger is indeed not used to recover energy, but merely as an electrical machine, which is actually powered by energy recovered upon braking and stored in batteries.

What if the e-turbo solution actually trialled by Audi on the R18 was following the same principle ? That would at least be consistent with Audi's latest declarations.

In the affirmative, such an e-turbo solution will not be beneficial in terms of the amount of energy being recovered and Audi would need to find another solution to improve energy recovery, e.g. by adopting a more powerful ERS-K.

[gwyllion]

Originally Posted by MyNameIsNigel

I find this part a bit intriguing:

That just means that they can change ERS class next year.

[chernaudi]

Current rules state that the teams can start on re-homologation of they hybrid systems between season's end before the Paul Ricard test in March.

And of course if they change the tub design to accommodate a "legality bump" for a truer fastback design (Toyota are rumored to be looking at something similar), they have to get the tub re-approved by the ACO.

I don't think that Audi would run two flywheels for packaging reasons (I can't see how two flywheel systems could fit in the R18's cockpit), so it'd have to be a bigger flywheel or a flywheel with a second, more dimensionally compact supplementary system of either supercapcitors or a battery, especially if they go 6MJ, which when you combine the flywheel with the e-turbo, is entirely possible.

[TF110]

I wonder if they shelved it because it stole engine efficiency. Toyota boss mentioned that in an interview about engine solutions.

[MyNameIsNigel]

Originally Posted by TF110

I wonder if they shelved it because it stole engine efficiency. Toyota boss mentioned that in an interview about engine solutions.

This all ultimately depends on the solution being used.

The "conventional" F1-style electric turbo-charging principle may not be the best solution from the point of view of efficiency due apparently to increased back pressure created by the electrical turbine, but there are evident alternatives to such a solution.

One is the solution used by Porsche where the turbine used to generate and recover energy is separate from the turbocharger and located in a bypass to operate as some sort of wastegate (so I understand). Porsche do seem to be in a position to make this work without compromising efficiency.

Another solution is the one used on the RS5 TDI Concept, which does not rely upon the use of any turbine placed in the exhaust flow to recover energy from the exhaust gases, but rather on an electric compressor used to supplement a conventional turbocharger and reduce turbo-lag.

The more I think about this, the more I believe that Audi might have actually trialled the principle that is demonstrated by the RS5 TDI Concept, rather than an F1-style electric turbo-charging system. Or maybe did they try both systems ?

In any event, it would seem that Audi will have to be quite audacious if they want to be more competitive next year. In recent declarations, Laudenbach did suggest that they may have a closer look at the solution being used by Porsche.

[cokata]

Originally Posted by MyNameIsNigel

This all ultimately depends on the solution being used.

The "conventional" F1-style electric turbo-charging principle may not be the best solution from the point of view of efficiency due apparently to increased back pressure created by the electrical turbine, but there are evident alternatives to such a solution.

One is the solution used by Porsche where the turbine used to generate and recover energy is separate from the turbocharger and located in a bypass to operate as some sort of wastegate (so I understand). Porsche do seem to be in a position to make this work without compromising efficiency.

Another solution is the one used on the RS5 TDI Concept, which does not rely upon the use of any turbine placed in the exhaust flow to recover energy from the exhaust gases, but rather on an electric compressor used to supplement a conventional turbocharger and reduce turbo-lag.

The more I think about this, the more I believe that Audi might have actually trialled the principle that is demonstrated by the RS5 TDI Concept, rather than an F1-style electric turbo-charging system. Or maybe did they try both systems ?

In any event, it would seem that Audi will have to be quite audacious if they want to be more competitive next year. In recent declarations, Laudenbach did suggest that they may have a closer look at the solution being used by Porsche.

The F1 solution is the more complex and the better of the 2. The porsche one is easier to do. The F1 cars don't use a wastegate (there is one there only for a backup in case the MGU-H fails) and they basically use the MGU to control the speed of the Turbine. The f1 solution should be lighter and capture more energy.

I'm curious does anyone have any sort of a estimate what kind of power can be generated by the MGU-H. Would it possible to run the engine without an alternator, because if it is possible it would make it very viable even for Toyota to have a similar system

[ederss7]

And if Audi used 2 ERS-K like Toyota does? Would it be possible? Wouldn't it be a "simpler" solution?

[cokata]

Originally Posted by ederss7

And if Audi used 2 ERS-K like Toyota does? Would it be possible? Wouldn't it be a "simpler" solution?

Well the flywheel should have the necessary power density to be able to take the current from 2 MGUs during braking

[gustavobamba]

Originally Posted by cokata

Well the flywheel should have the necessary power density to be able to take the current from 2 MGUs during braking

But a second MGU increases weight, and weight is not good for overall performance.. right?!?!?

[MyNameIsNigel]

Originally Posted by ederss7

And if Audi used 2 ERS-K like Toyota does? Would it be possible? Wouldn't it be a "simpler" solution?

Possible, yes, but most likely not the sort of avenue that Audi would take in view of the impact on overall weight and weight distribution. That R18 is already sufficiently heavy at the rear.

This being said, an ERS-H would also imply additional weight at the back.

ERS-K or ERS-H, that is the question.

[ederss7]

How much weight are we talking about? For example, Fassler weighs 78kg while Treluyer weighs 68kg. That means when Fassler is driving the car is 10kg heavier.

[TzeiTzei]

Originally Posted by cokata

I'm curious does anyone have any sort of a estimate what kind of power can be generated by the MGU-H. Would it possible to run the engine without an alternator, because if it is possible it would make it very viable even for Toyota to have a similar system

I've seen figures of around 100kW.

[cokata]

They have to find a weight gain from somewhere anyway. Looks very likely that both Porsche and Toyota will jump to 8mj, so Audi need to try to go to at least 4mj preferably 6mj considering that there is almost no fuel penalty for going from 6mj->8mj for the petrol cars.

[cokata]

Originally Posted by TzeiTzei

I've seen figures of around 100kW.

That's at peak power, haha no way. Unless we are talking of >800bhp @ 20,000rpm+

[TzeiTzei]

Originally Posted by cokata

That's at peak power, haha no way. Unless we are talking of >800bhp @ 20,000rpm+

There are some awfully long threads about this at f1technical. Go check them out and see if you can find answers there.

[JoestForEver]

Originally Posted by cokata

That's at peak power, haha no way. Unless we are talking of >800bhp @ 20,000rpm+

Probably yes. For reference, the 2013 R18 has 2 MGUs at the front with 80kw each and a flywheel system of 36,000-40,000 rpm.
This year, the official press release talks about no less than 237bhp from a single MGU.

[Simmi]

Tom Kristensen has called a press conference for 1pm tomorrow in Denmark. Dr Ullrich will also be in attendance.

Surely that's going to be a retirement announcement?

[MyNameIsNigel]

Originally Posted by JoestForEver

Probably yes. For reference, the 2013 R18 has 2 MGUs at the front with 80kw each and a flywheel system of 36,000-40,000 rpm.
This year, the official press release talks about no less than 237bhp from a single MGU.

I believe that the question was actually relating to the power of the relevant ERS-H (or "MGU-H" to use the F1 terminology). It is worth reminding however that there is no such thing as a "MGU-H" in the context of the LMP1 regulation. Under the LMP1 rules, the MGU ("Motor-Generator Unit") is specifically defined as a "drive machine mechanically linked to one of the drive trains" (the engine - and components thereof - being not defined as a MGU).

In that respect, it is safe to say that the electrical turbine used by Porsche as part of their ERS-H does not fall under the definition of MGU. The same would be true - I believe - for any e-turbo (in whatever form) as such a system would have to be considered as being an engine component.

This may have interesting implications should a competitor (e.g. Audi) contemplate to adopt an electrically-assisted turbocharger/supercharger solution (as demonstrated with the RS5 TDI Concept) to improve engine performance as the energy consumed by such a system would not be subject to any restriction. Only the energy released through the MGU(s) is limited by the rules.

Now, putting the semantics about the "MGU-H" aside, I still have no real clue as to how much energy an ERS-H can recover from the exhaust gases.

[MyNameIsNigel]

Originally Posted by Simmi

Tom Kristensen has called a press conference for 1pm tomorrow in Denmark. Dr Ullrich will also be in attendance.

Surely that's going to be a retirement announcement?

I would have hoped to see him race one more year, but a retirement after this season would not be totally unexpected.

[CTD]

Originally Posted by Simmi

Tom Kristensen has called a press conference for 1pm tomorrow in Denmark. Dr Ullrich will also be in attendance.

Surely that's going to be a retirement announcement?

According to the casual danish fan, he is either switching to Porsche as Audi is going to F1, or becoming the Le Mans team boss as Dr. Ullrich will do the Audi F1 team.

But unfortunately it will most likely be a retirement notice - most likely after the WEC 2015 season.

[J Jay]

Almost certainly a retirement. He's had a good innings, has Sir Tom. His tearful tribute last year will remain long in the memory.

So who gets first dibs? Bonanomi? Albuquerque? Outside bet on Jarvis?