Audi LMP1 Discussion

[gwyllion]

Originally Posted by knighty

hi gwyllion, thanks for confirming the motor-generator weight, mine was an approximation at 20Kg, but 45Kg is obviously a very heavy piece of kit!........I'm pretty sure the F1 KERS systems are in the region of 20-30Kg, it was a rough comparison in all honesty.......... but the point still stands, the williams flywheel system is one heavy mo-fo........it will be interesting to see how they all compare, for sure I cant see pug and Toyotas systems being anywhere near as heavy

It is not clear to me to what extent Audi will use the Porsche/Williams system. Will they connect the electric motors to the front wheels or to the gearbox? Will they only use the flywheel battery or also additional components (electronics, electric motor/generators, ...)?

Personally I doubt that it will be connected to the front wheels, because there is not enough space in the nose.

One of the motivations for the V6 TDI engine was that it is short enough to fit a hybrid system between the engine and the gearbox. On the spy pictures from Sebring a bulge can be seen in the engine cover, presumably because this is where the flywheel is positioned: http://www.mulsannescorner.com/AudiR...2011-anon1.JPG

Originally Posted by knighty

but at the nurburgring 24hr race they ran it between 28K-36K for safety reasons and were able to store 680KJ maximum.......the ACO rules state that only 500KJ can be applied (used) between braking events, so this williams energy storage system may be limited for LMP1 use, as its going to almost completley discharge between braking events........but perhaps thats ok???......who am I to say!!!

It makes no sense to recover and store more energy than you are allowed to release. So fully discharging the battery after every braking zone seems the way to go.

That means that the battery capacity should be only slightly bigger than 500 kJ. Coincidence or not, but the specification of the Flybrid CFT KERS quotes "540 kJ of storage"

[NelisB]

Originally Posted by gwyllion

It is not clear to me to what extent Audi will use the Porsche/Williams system. Will they connect the electric motors to the front wheels or to the gearbox? Will they only use the flywheel battery or also additional components (electronics, electric motor/generators, ...)?

Personally I doubt that it will be connected to the front wheels, because there is not enough space in the nose.

One of the motivations for the V6 TDI engine was that it is short enough to fit a hybrid system between the engine and the gearbox. On the spy pictures from Sebring a bulge can be seen in the engine cover, presumably because this is where the flywheel is positioned: http://www.mulsannescorner.com/AudiR...2011-anon1.JPG
It makes no sense to recover and store more energy than you are allowed to release. So fully discharging the battery after every braking zone seems the way to go.

That means that the battery capacity should be only slightly bigger than 500 kJ. Coincidence or not, but the specification of the Flybrid CFT KERS quotes "540 kJ of storage"

When you're able to store more energy you don't have to have that 2 seconds of braking to get it fully recharged because there is still a bit left... That means once it's charge has been released you only need to recharge with a sub 2 second brake event to get the maximum useable amount again.

[gwyllion]

BTW How It Works: Porsche 911's GT3R Hybrid Flywheel is worth the read.

The article lists two important advantages of the Williams flywheel battery. (1) It allows for fast charge/discharge cycles, making it similar to an ultracapacitor. However, an ultracapacitor with the same capacity would weigh more. (2) It has good durability, which makes it very well suited for endurance racing.

Under the extreme power charge/discharge cycles of racing, even a lithium ion battery would face durability issues. Kristen estimates that a battery would have to be replaced three times during a race like the 24 Hours of Nurburgring, where the 911 nearly won in May 2010, after leading for over eight hours. The best current lithium ion batteries will last for a claimed 20,000-plus charge cycles, and hybrid batteries are typically only partially charged and discharged, which maximizes their life-span. Kristen claims the flywheel will last over one million cycles.

[gwyllion]

Originally Posted by NelisB

When you're able to store more energy you don't have to have that 2 seconds of braking to get it fully recharged because there is still a bit left... That means once it's charge has been released you only need to recharge with a sub 2 second brake event to get the maximum useable amount again.

Clearly a tradeoff must be made between the capacity of the battery and the power output of the motor/generator.

The hybrid Toyota Supra for instance had a 150 kW electric motor at the rear. Similarly the 911 hybrid 2.0 has 2 x 75 kW electric motors at the front. That means that 3.33 seconds of braking is sufficient to recover the necessary amount of energy. In this case, a battery capacity of 500 kJ is probably enough.

The Zytek ZPH solution on the other hand only has one 40 kW electric motor at the rear. That system needs 12.5 seconds to recover 500 kJ. With this system you probably need a bigger battery, because there will be braking zones which last shorter than the required 12.5 seconds to fully recharge the battery.


Of course weight will also play a big factor in the design process: bigger batteries and bigger motors weigh more and require more cooling. Furthermore, there are limitation on how much charge/discharge rate for the underlying battery technology, etc.

[gwyllion]

Audi Sport accepted yet another award to start the new year: the innovative V6 TDI power plant from the Le Mans winning Audi R18 TDI was honored by a special interest magazine.

Distinguished start: a first award goes to Audi Sport to start the year. A panel of judges for the trade journal Race Engine Technology voted the Audi V6 TDI as ‘Race Engine of the Year 2011’. The particularly compact and lightweight power unit develops more than 397 kW (540 hp) and propelled the Audi R18 TDI last year. Audi won the 24 Hours of Le Mans for a tenth time with it.

source: https://www.audi-mediaservices.com/p...ewsletter.html

I think that the technical specifications of the engine (wide angle V6, exhaust inside V, single VTG turbo) influenced the decision, because the Peugeot V8 HDI engine is equally powerful and more efficient.

[CTD]

Originally Posted by gwyllion

source: https://www.audi-mediaservices.com/p...ewsletter.html

I think that the technical specifications of the engine (wide angle V6, exhaust inside V, single VTG turbo) influenced the decision, because the Peugeot V8 HDI engine is equally powerful and more efficient.

I never really understood why Audi has two engines voted Engine of the year. When both Peugeot's V12 and V8 is clearly the best. But of course Peugeot's engine isn't innovative, and Audi's is, that must have counted the last bit.

[alexkiller8]

analyzing the .pdf of almost races of ILMC 2011, peugeot had a much better fuel economy only at LM, in my opinion just because audi choiced an engine map more powerfull than peugeot that choiced a more reliable/fuel efficency one.
However as happened in previous models (V12 peugeot more with almost +10% of torque than V12/V10 audi) me too think that if we make a comparison betwen the 2 actual engines in similiar configuration, the peugeot one is more powerfull than the audi one.

[gwyllion]

Maybe I am reading to much into this, but the last motorsport newsletter of Audi confirms that Lotterer will stay with Audi in 2012.

Family ties: Audi factory driver André Lotterer will contest the historical Legend Boucles de Spa rally on February 18. He drives a Porsche 911 SC RS as tribute to his father who built and raced such a car with his RAS team in the 1980s.

[CTD]

Originally Posted by gwyllion

Maybe I am reading to much into this, but the last motorsport newsletter of Audi confirms that Lotterer will stay with Audi in 2012.

Don't think you read to much into it

[Articus]

Sure hope so. He's one impressive young man!

[chernaudi]

Even though it hasn't been announced publicly, Andre and Ben are likely Audi factory drivers now...well, except for the fact that the wording of that article sort of spells it out for Lotterer, now doesn't it?

It seems that they'll be in one of the Joest R18's full time next year, but we'll have to wait for Audi to reveal driver lineups, which will probably happen when the R18 hybrid is publicly launched.

[ronnie peterson]

Lotterer / Tréluyer for WEC with Fassler joining them on Sebring, Spa, Le Mans.
Tom K / McNish with Dindo on longer races.
Dumas / Bernhard / Rockenfeller for the third car on longer races.

I can't see that lineup changing for this years programme. Maybe Bonanomi can stand in for Rockenfeller since Rocky wants to focus more on DTM.

[gwyllion]

Another hint that Lotterer is doing WEC this year:

Originally Posted by @Andre_Lotterer

To bad Peugeot had to pull out,WEC was gonna be epic with them! Sad for them and our sport! Thanks for making competition real! We'll miss u

source: http://twitter.com/#!/Andre_Lotterer...60261694234624

[Wippermann]

http://www.mfspeed.ch/news/blog.html

According to Marcel Fässlers Blog, he will take part in the Audi Fitness Program. Probably that means, he is going to be one of Audis Factory Drivers in 2012!

[Articus]

So the Peugeot 908 and the Toyota TS030 allegedly all use J-Dampers? Can anyone comfirm that the Audi R18 uses some kind of J-damper?

[gwyllion]

I have never seen convincing evidence that the old or new Peugeot 908 had inerters. Maybe the front suspension had them hidden in the nose, but on all the pictures that I have seen of the rear, I never saw them.

On the pictures of the R18 inerters were never found either.

Unless the inerters are integrated in the shock dampers. However, as far as I can tell only Penske has such dampers and Audi and Peugeot use Ohlins.

[Articus]

I heard the Peugeot had an inerter system in the front end . Thats why they where so keen to blanket the nose all the time.

[gwyllion]

At the end of the old 908 lifecycle and with the new 908 they did not bother to put a blanket on the front suspension. See for instance http://photos.speedtv.com/gallery/AL...hnical_Gallery

[TF110]

Forgive my ignorance, but what're J-dampers? And are they beneficial?

[Articus]

I guess it was just a rumour then. Interesting nonetheless. They seemed to be hiding something for the first 3 years of the old 908 when they where significantly quicker than the R10 what could it have been?

[cmk]

Originally Posted by TF110

Forgive my ignorance, but what're J-dampers? And are they beneficial?

https://scarbsf1.wordpress.com/2011/...fluid-inerter/

Some information on inerters, TF110. Their benefits or lack thereof may depend on who you ask and the nature of the application. In the case of the recently-banned fluid inerter at the core of that article, it was believed to be employed primarily to control pitch under braking. In the case of an F1 car that prevents the flexible and nose-down wing (due to rake) from grounding under braking, while still allowing you to run a softer suspension to help with grip.

[TF110]

I see, so almost like this new Ride Height system that was banned just a couple days ago in F1.

[cmk]

Originally Posted by TF110

I see, so almost like this new Ride Height system that was banned just a couple days ago in F1.

The Renault (Lotus) fluid inerter is exactly what was banned a couple of days ago. Some suggested that other teams looking to use it had come a little too close to calling it a ride height adjuster rather than a braking aid.

[gwyllion]

The Lotus/Renault system that got banned recently, is a reactive ride height system. It has nothing to do with their fluid inerter patent.

As I mentioned in the Toyota topic, there already is a discussion dedicated to this topic: Peugeot 908 secret=Ferrari F1's J-Damper.

[cmk]

Originally Posted by gwyllion

The Lotus/Renault system that got banned recently, is a reactive ride height system. It has nothing to do with their fluid inerter patent.

As I mentioned in the Toyota topic, there already is a discussion dedicated to this topic: Peugeot 908 secret=Ferrari F1's J-Damper.

What I've read on the nature of RRH systems suggests that the use of a fluid inerter is far from unrelated. Given that the technical bulletins involved are not public it is difficult to know for sure, but surely the type of reactive systems the FIA is talking about include hydraulically linked suspensions and fluid inerters used to adjust ride height (pitch) under braking. That means that while the inerter itself might not be banned, the system it was designed for/along with is. Anyway, this is straying off the topic of inerters in P1s...