Audi LMP1 Discussion

[MulsanneMike]

Originally Posted by chernaudi

Fine, I'll wait until Mike and Sam's photos get posted. But why have the rear suspension attach to extensions from the bellhousing instead of the gearbox casing, which at least is in theory a simpler arrangment?

Either Audi have something going on with the gearbox as far a an easily removed module, or they know something about the bellhousing extensions and suspension mounts proving some other advantage.

It's pretty straight forward: the gearbox wall proper now doesn't have the be as robust as it isn't handling suspension loading. So thinner wall and a much simplified casing in general. All = less weight, and less weight high up.

[chernaudi]

And what's up with the louvers over the engine bay on the R18? At Sebring and Paul Ricard, the R18's ran with the louvers opened. At the LM test, Spa, and Monza, the R18s ran with them closed. A better safe than sorry measure?

And I wonder what Mike can make of the R18 photos from Monza? I can't tell if Audi are going for simply reduced drag, or trying to produce more downforce while minimizing drag--the front fender profile of the #2 R18 is more like the R8 and R10 from the side, the the rear deck has a raised trailing edge across it's entirety.

Also seems to be newly manufactured parts (completed after Spa?), as there was duct tape covering the holes in the front fenders for whatever Audi may attach there at a later date, probably dive planes (and over the LED air intakes it seems, too).

Maybe Audi simply appreciate that Peugeot aren't gonna sit still and watching the 908's at Spa may've lead to to the new aero kit being tested. And the fact that it was tested alongside the old spec means that Audi is likely trying to find out if one's better than the other, and may lead to standardizing on one over the other, or a hybrid of the specs?

[chernaudi]

BTW, interesting analysis Mike. I wonder where Audi found inspiration for this, because I don't even think that F1 teams have taken it this far (yes, I'm aware that they use CFC gearbox casing, or at least ones partly constructed from CFC). If what Mike has said is correct (and only Audi Sport know for sure the motivation behind this), could the R18's gearbox be probably the lightest out there on an prototype right now?

And if this does suitably reduce stresses on the gearbox casing, they can have a lighter gearbox without sacrificing reliability, which opens doors for servicing (someone has to carry it, even to a dolly sitting next to the car--at least that guy's job is easier!), as well as it just being lighter (more room to play with ballast, more weight up front, etc). Only concern for me is durablitly--not in an of itself under race conditions, but in an accident, though I suppose that a normal magnesium or aluminum casing would be just as prone to damage if the car hits something hard enough.

[RJC_pt]

Whats new to it? I think i remember that ate least in Gr. C Allard had a carbon structure around th e gearbox... and i think it was not a lone exemple.. mmmm.

Found it

Reynard 2KQ(thanks mike)

It seems to be to big of a setup for F1.

[gwyllion]

Originally Posted by RJC_pt

Whats new to it? I think i remember that ate least in Gr. C Allard had a carbon structure around the gearbox...

http://www.mulsannescorner.com/allardj2x-5.html has more pictures of the Allard's solution.

[gwyllion]

Originally Posted by gwyllion

Pictures of the Monza test can be found on the following website:
http://www.motorsportuniverse.com/AudiR18.html
https://picasaweb.google.com/1030266...283/AudiR18TDI
http://www.422race.com/foto/?g_id=736

Another gallery with 41 high quality pictures: http://www.flickr.com/photos/allmoto...7626757453288/

Yet another video from the Monza test: http://www.youtube.com/watch?v=sSzs3pPFQg4

[gwyllion]

Audi is clearly testing new aero parts. I guess they are preparing the high downforce package.

Look at the rear wing on these two pictures:


Note that the #1 car is running with 2 full size dive planes. On other pictures the #1 is running with a single dive plane.

It also seems that the bodywork between the front wheel arch and the nose has been opened on the #2 car:

[chernaudi]

Strange that Audi would be testing high downforce aero at Monza. This close to LM, I'd think that Audi would testing for LM almost exclusivly.

But Imola is only about 3 weeks after LM, and is definently a high downforce track.

Either that, or they're doing this because Monza offers up more fast corners that EuroSpeedway does--it might be a good track for DTM and touring cars, but not for LMPs and the high speeds that they can acheive.

Maybe Audi is trying to cover all the bases to try and win some ILMC races after LM win lose or draw there.

[MihokS5]

Excellent notes gwyllion

[CTD]

Originally Posted by chernaudi

Strange that Audi would be testing high downforce aero at Monza. This close to LM, I'd think that Audi would testing for LM almost exclusivly.

But Imola is only about 3 weeks after LM, and is definently a high downforce track.

Either that, or they're doing this because Monza offers up more fast corners that EuroSpeedway does--it might be a good track for DTM and touring cars, but not for LMPs and the high speeds that they can acheive.

I think Audi are doing this to learn about there options for Le Mans. Example is if the Peugeot aren't quicker down Mulsanne, then Audi can but on a higher downforce level and gain even more through the corners (or the other way around)

[MulsanneMike]

Originally Posted by gwyllion

Audi is clearly testing new aero parts. I guess they are preparing the high downforce package.

Look at the rear wing on these two pictures:


Note that the #1 car is running with 2 full size dive planes. On other pictures the #1 is running with a single dive plane.

It also seems that the bodywork between the front wheel arch and the nose has been opened on the #2 car:

Thing that strikes me about the two wing comparisons isn't so much the height (there is that too), but the angle of the entire wing assembly. Though oddly, the one you would say is high df with the twin diveplanes, seems to have the lower wing plus most backed out angle. They most certainly are VERY busy! Never seen this amount of development. A shame they really are only committed to a handful of races. ILMC hasn't been good to the ALMS or LMS.

[pederb]

That is a great looking car, can't wait to see it at Le Mans

[MulsanneMike]

Looking at the high res flickr images it most certainly is the case of rear wing main plain assembly angle.

[gwyllion]

Originally Posted by MulsanneMike

Thing that strikes me about the two wing comparisons isn't so much the height (there is that too), but the angle of the entire wing assembly. Though oddly, the one you would say is high df with the twin diveplanes, seems to have the lower wing plus most backed out angle.

I never wanted to suggest that the #1 is high downforce. For some bizar reason, the #1 had the double dive plane on the one picture I chose. On all the others, the #1 has the single dive plane we know from Sebring/Spa/Le Mans.

On this video the #1 is blasting by the #2. That suggest that the #1 car is doing the endurance run (i.e., long runs lapping in the 1:28s) and that the #2 car is used for aero development (i.e., short runs).

Originally Posted by MulsanneMike

They most certainly are VERY busy! Never seen this amount of development. A shame they really are only committed to a handful of races. ILMC hasn't been good to the ALMS or LMS.

At this rate of development you have the archive your news section every month, instead of every 2 months

[chernaudi]

That seems to be why Audi have had at least two cars at each test they've done (and three at Paul Ricard)--one car to do primarily endurance runs, and another to do R&D work.

Other than the #2 pulling out of the way of the #1 being an indicator of which is doing what type of testing, but the #2, like at Paul Ricard and LM, had the tire sensors on it.

And could the #1 Audi with the twin diveplanes be an intermediate/medium downforce package?

[gwyllion]

Originally Posted by chernaudi

Other than the #2 pulling out of the way of the #1 being an indicator of which is doing what type of testing, but the #2, like at Paul Ricard and LM, had the tire sensors on it.

There are a lot more pictures of the #1 than of the #2. In the flickr album of Daniele Paglino I counted 26 pictures of #1 and 12 pictures of #2 (and 3 unknown). More pictures = more laps

Originally Posted by chernaudi

And could the #1 Audi with the twin diveplanes be an intermediate/medium downforce package?

Don't be fooled by the double dive planes. The #1 car only had double dive planes on 5 of the 26 pictures. There are also pictures of the #2 with double dive planes; e.g., http://www.flickr.com/photos/allmotorsport/5736683921/

[chernaudi]

HPD claim that their twin diveplane nose is for an intermediate/medium downforce package. The HPD cars, though have only the LM and some higher downforce package for LMP2 has only two packages that the teams can run.

I wouldn't hold it against Audi that the LM nose and tail with the diveplanes/taller tail gurney could be an intermediate/medium downforce package, but could just be a test to see how it would work. Remember, Audi are testing this at Monza (and without the chicane on the front straight), which on face value alone seems to be an odd choice, but Audi know what their motives are, and we can only guess until they say something about the test (which I think that we won't hear much until the Paul Ricard test).

Odd also how it's almost always the "#2" that has the tire sensors on it.

[gwyllion]

Originally Posted by chernaudi

Odd also how it's almost always the "#2" that has the tire sensors on it.

Why is this odd? According to Radio Le Mans Audi has at least 6 chassis. There are the 3 race chassis that have the paint jobs. So there are probably 3 test/development chassis in black carbon. The chances are high that the 2 cars in Monza are the same as in the Sebring tests.

[gwyllion]

Originally Posted by chernaudi

That seems to be why Audi have had at least two cars at each test they've done (and three at Paul Ricard)--one car to do primarily endurance runs, and another to do R&D work.

Other than the #2 pulling out of the way of the #1 being an indicator of which is doing what type of testing, but the #2, like at Paul Ricard and LM, had the tire sensors on it.

Because the Italians that were on site say so

According to http://www.422race.com/2011/le-foto-...-audi-a-monza/ the #1 Audi was doing long stints (lapping low 1:28s) and the #2 Audi did shorter stints with a slower pace.

[gwyllion]

Mike's analysis of the new aero: http://www.mulsannescorner.com/newsmay11.html

[chernaudi]

Design drawings and sketches on the Pannullo blog: http://lemansprototypes.over-blog.it/

[gwyllion]

Short interview with Dr. Ullrich: http://www.lemans.org/en/races/24h/u...air-_3769.html

An interesting comment:

Finally, will the German carmaker follow the lead of French rivals with a hybrid prototype? The response of Dr. Ullrich was clear: "No, for me, the hybrid, it's just marketing!"

[chernaudi]

Only reasons why I can see Audi going with a hybrid version of the R18 is:

1--marketing of their hybrid road cars and trying to improve them, or

2--if Peugeot can get the 908 HY working and can get some fuel mileage advantage out of it, which the 908 may already have for all we know from the test day.

If Peugeot can get it to work, look for Audi to follow suit with their own hybrid system--after all, it took years of the Pugs being nearly 10mph faster down the straights at LM for Audi to adopt a closed car.

[gwyllion]

That comment of Ullrich contradicts what Audi said earlier about the R18.

During development of the new LMP1 sports car the integration and future electrification of the powertrain and various possible concepts for energy recuperation have been taken into account.

"We are very conscious of such systems," explains Head of Audi Motorsport Dr. Wolfgang Ullrich. "In our opinion, just as soon as this technology proves to be the most efficient we will use it at Le Mans."

What Ullrich really meant is that they will not go the same route as Peugeot (i.e., lithium ion battery pack and electric motor/generator connected to gearbox).

I predict that Audi has a big surprise for next year: the R18 will get a waste energy recovery system instead of a kinetic energy recovery system! A KERS works very well when there are a lot of braking zones, which is not the case in Le Mans. Waste heat recovery on the other hand works best with full throttle.

In interviews about his global race engine concept Baretzky has repeatedly mentioned this type of technology:

Baretzky is a big fan of 'waste energy recovery systems' and was very disappointed with the FIA's bungled introduction of KERS to F1.

"The other thing that's very important that we should not lose sight of is all kinds of waste energy recovery systems. I don't say KERS. I say waste energy recovery by using the exhaust and turbo where you really could get more efficiency into a race car. When you use a small engine like an in-line four that gives you a lot of room in the car you have a lot of possibilities with the turbocharging system to get more energy out of what you are burning.

Baretzky is in regular dialogue with the EPA and says EPA officials share his enthusiasm for 'waste energy recovery systems'.

"When we were in Sebring I had a nice conversation for an hour with some people from the EPA. We are talking regularly now at least one or two times a year. We realize we have the same vision where at the end of the day we will get an energy-based type of racing that would take whatever shape or form of energy and make power out of it. We all agree on that and there's a broad agreement that some type of waste energy recovery system should be installed to give people a real incentive to develop new technologies which could really help road cars to save fuel and make the car more efficient and more environmentally friendly."

source: http://www.gordonkirby.com/categorie..._is_no228.html

Baretzky points out that an in-line, four-cylinder provides plenty of room for energy recovery systems.

"Small engines allow us to combine a lot of energy recovery systems. If you want to look at all the efficiency components you want to incorporate in the future, like waste energy recovery systems from the exhaust or the cooling system, then you need a little bit of space on the left and rightside of the engine. A four-cylinder gives you that space but a vee engine is the wrong thing to have because you are so limited in space. You have an exhaust system on both the left and rightside and you also have to double all the energy recovery systems which makes it very heavy, very complicated and very inefficient. So it's better to have the hot side on one side of the engine and the cool side on the other side so you can arrange all these things accordingly. That's the opportunity with the four-cylinder."

source: http://www.gordonkirby.com/categorie..._is_no257.html

The marketing people might not have allowed Baretzky to build the engine he wanted to (2.0 liter 4 cilinder turbo). With his "hot side inside" V6 TDI engine, he can still apply his favorite waste energy recovery system. I wonder which technology Baretzky will chose: electric turbo-compounding, mechanical turbo-compounding, thermo-electricity, ... If they use an electric system they can use it to replace the alternator or to power an electric motor connected to the wheels.

BTW there is a French company called heat2power that promotes a solution for racing and they explicitely mention Le Mans:

Waste heat regeneration increases the power of engines

The second reason why WHR is interesting for racing is that it can considerably increase the amount of power delivered by the engine while respecting the regulations. On gasoline race engines that run between 8000 and 11000 RPM we have seen power levels in the exhaust about 1.8 times as high as the power on the crankshaft. That means that there is a huge amount of power being lost. By simply converting a part of that into torque, the engine power is increased. Imagine what a 25% of regeneration efficiency can do. The heat2power system was designed to have high regeneration efficiency at high RPM and could thus achieve about 1.2 kW per kg added to the vehicle. The effect on laptimes is classified as "considerable", especially on tracks like Le Mans with long straights and few corners. The WHR would function at full power almost all the time.

The race series heat2power started to work for is the Le Mans Series but we expect Formula One to pick up very soon as well, even though the F1 engineering teams for the moment focus on WHR from the engine cooling system.

source: http://www.heat2power.net/en__markets_racing.php

[gwyllion]

In case you are wondering, the current LMP1 rules allow "recovery from the heat of the exhaust fumes" (article 1.13). However, I have no clue how the ACO can regulate such system.

There is a rule which says "the amount of energy used between 2 braking must not exceed 0.5 MJ". Waste heat recovery is working all the time and does not rely on braking energy.

And there is the "famous 400 meter at 60 km/h on hybrid only" rule. The engine needs to be running in order to produce enough waste heat.