[WEC] Porsche Prototype Discussion

[Dario911]

Originally Posted by Gingers4Justice

This is Porsche. Their marketing strategy often involves no marketing strategy, by which I mean they turn up to Le Mans, win it magnificently, and then all of a sudden we (the enthusiasts) have an urge to by a Porsche (not including me in this obviously, my Panda is somewhat easier to insure at my age than a 911). As Rennen said earlier, this is an enthusiast's sport and they know it. If you want to market your cars to Joe Public and sell your Cayennes or whatever to them, stick an ad on the tele or in a newspaper...that will do you more good than an F1 podium every now and again. And that's what they'll do.

To some people - most, in fact - "Porsche" is a brand name that is desirable. But that's built on a pedigree that we, the enthusiasts, have helped create. Porsche have obviously felt the need to continue that.

Ergo, every driver whose bottom touches the seat of this LMP1 Porsche will be the best driver available when the contracts are signed.

100% right!

[avvelenamento]

Originally Posted by Maelochs

If you mean, can it be expanded to eight megajoules ... no clue. The flywheel stores the energy as rotation, so to increase storage, either mass or speed would need to increase. Harvesting and discharging shouldn't be a problem but storing the energy might be ... but I am not an engineer.

EDIT: "Works for Audi!" Not yet. The current system which is much much smaller has worked well for both Porsche and Audi in endurance racing, but as far as I know, no test results for the much larger 2014 system have been published.

I assume the engineers at Porsche and Audi can make it work. They seem to be pretty good at their jobs.

They? porsche and audi flywheels used in 911 GT3R-H and R18 e-tron have been done by WHP (williams hybrid power). Anyway, supercapacitors or batteries are the best hardware to storage 8MJ.

[Maelochs]

"I assume the engineers at Porsche and Audi can make it work. They seem to be pretty good at their jobs."

"They" refers back to "the engineers at Porsche and Audi," who do seem to be pretty good at their jobs.

They might no have developed the flywheel system they use, but they did design and build every other part of the cars except the tires, pretty much.

[wolfhound]

Originally Posted by avvelenamento

They? porsche and audi flywheels used in 911 GT3R-H and R18 e-tron have been done by WHP (williams hybrid power). Anyway, supercapacitors or batteries are the best hardware to storage 8MJ.

It depends on how long you need to store the energy and recharge rates.
Flywheels will lose energy over time due to friction but should have large capacity/weight ratio. To increase flywheel capacity speed and diameter are important weight not so much. effictively they are motor generators and can therefore be designed to charge/discharge quickly. Batteries need more volume & weight to increase capacity so the larger the storage requirement the more weight and volume required. I do not have enough knowledge of super capacitors to comment but they seem to work well in the Toyota.

[avvelenamento]

Originally Posted by Maelochs

"I assume the engineers at Porsche and Audi can make it work. They seem to be pretty good at their jobs."

"They" refers back to "the engineers at Porsche and Audi," who do seem to be pretty good at their jobs.

They might no have developed the flywheel system they use, but they did design and build every other part of the cars except the tires, pretty much.

They can build every other part but not the carbon monocoque, that is most important part of the racecar . You know, r8, r10, r15 and r18 monocoques are produced by dallara, that being a leader company of motorsport technologies is also implied in the project/design. Porsche AG has more know how than audi about carbon.

[avvelenamento]

Originally Posted by wolfhound

It depends on how long you need to store the energy and recharge rates.
Flywheels will lose energy over time due to friction but should have large capacity/weight ratio. To increase flywheel capacity speed and diameter are important weight not so much. effictively they are motor generators and can therefore be designed to charge/discharge quickly. Batteries need more volume & weight to increase capacity so the larger the storage requirement the more weight and volume required. I do not have enough knowledge of super capacitors to comment but they seem to work well in the Toyota.

Flywheel greatest advantage is that has not any "shaft" linked to the thermal engine. If flywheels fail the car keep on running powered only with the thermal engine. If an hybrid system integrated to the engine and transmission like the toyota one fails, the car retires. I think that next year we will see hybrid semi-permanent AWD lmp1 work cars. A first hybrid system integrated to the engine to supply power to the rear wheels and a second indipendent flywheel hybrid system on the front wheels.

[Mike E]

Originally Posted by avvelenamento

Flywheel greatest advantage is that has not any "shaft" linked to the thermal engine. If flywheels fail the car keep on running powered only with the thermal engine. If an hybrid system integrated to the engine and transmission like the toyota one fails, the car retires. I think that next year we will see hybrid semi-permanent AWD lmp1 work cars. A first hybrid system integrated to the engine to supply power to the rear wheels and a second indipendent flywheel hybrid system on the front wheels.

Good point. They are allowed to use two hybrid systems next year, aren't they?

[Maelochs]

"You know, r8, r10, r15 and r18 monocoques are produced by dallara, that being a leader company of motorsport technologies is also implied in the project/design. Porsche AG has more know how than audi about carbon."

Yes. Dallara built the monocoques, or at least mass-produced them. I don't doubt Audi could lay up a monocoque of Audi quality if they so desired. Didn't Audi build the carbon gearbox and sub-frame in-house? And we both agree the vast majority of the rest of the cars are pure Audi (I am sure Audi didn't fabricate the wires, the gauges, the brake lines ... )

Let's not lose sight of the point here: I maintain that the engineering staff at Audi is very skilled. Is That what you dispute??

Anyway, I haven't heard anything about what direction Audi might go with its 2014 car, main power plant or hybrid systems. based on the past 14 years, I think they will come up with something.

[Dario911]

Originally Posted by avvelenamento

They can build every other part but not the carbon monocoque, that is most important part of the racecar . You know, r8, r10, r15 and r18 monocoques are produced by dallara, that being a leader company of motorsport technologies is also implied in the project/design. Porsche AG has more know how than audi about carbon.

Right point. Porsche produces by itself carbon monocoque of its cars (GT1 1998, RS Spyder), while Audi always cooperates with Dallara Engineering.
Anyway, it doesn't mean Audi engineers are not very skilled, and I think they may produce by themselves the carbon monocoque, if they only need to do it.
I think they prefer to design the chassis, letting to be Dallara to build it to simplify production cycle.

[Starfish Primer]

Peugeot also used an external company to build the carbon monocoque

[avvelenamento]

I have no intention to create any dispute, simply because I don't care about what audi and porsche do. Audi sport is the leader group about sportscars innovations and performances, no doubt on this. Porsche will be a great challenger, but if 2014 regs will show to be still too much favourable to diesel again, I fear that will remain terribly hard for a gasoline work car to compete against audi.

Answering to Mike E, toyota revealed that the 2014 car will be powered by the same but update 3.4 V8 working both as thermal engine and charger for the two hybrid system. One for the rear wheels, one for the front.

http://www.theepochtimes.com/n3/1175...use-v8-engine/

[avvelenamento]

Coming back to who made what mood, the hybrid system of the 908 Hy4 was rumored to be a ferrari product. Such a shame that this great car never raced and now is disassembled somewhere inside peugeot sport HQ

[MyNameIsNigel]

Originally Posted by avvelenamento

Answering to Mike E, toyota revealed that the 2014 car will be powered by the same but update 3.4 V8 working both as thermal engine and charger for the two hybrid system. One for the rear wheels, one for the front.

http://www.theepochtimes.com/n3/1175...use-v8-engine/

Another source (namely sportauto.de) suggests Toyota may use a 5L V8 instead of the current 3.4L V8.

[avvelenamento]

Thanks, your source is more recent than mine, there should be the truth behind the rumor. Maybe toyota engineers realized that the high-rev 3.4 V8 doesn't give enough torque in low-mid rev to respect the mandatory fuel flow. So switch for a larger engine that basicly should work as a low-mid rev torque generator.

[TF110]

The same reasoning was talked about with regards to the engine they'll supply to Rebellion.

[Articus]

Originally Posted by MyNameIsNigel

Another source (namely sportauto.de) suggests Toyota may use a 5L V8 instead of the current 3.4L V8.

The engine will sound awesome for sure! However would Toyota be interested in such a large engine. They picked the V8 so it was small and lightweight. Wouldnt make sense to bump up the power to what end if they have so much more freedom on the energy recovery side of things.

[Dario911]

Originally Posted by avvelenamento

Coming back to who made what mood, the hybrid system of the 908 Hy4 was rumored to be a ferrari product. Such a shame that this great car never raced and now is disassembled somewhere inside peugeot sport HQ

It was a rumor, but has never been confirmed.
According to other rumors, it was used a Pug 908 prototype to test Ferrari KERS, but this was not related to 908 Hybrid project.

[Maelochs]

The article avvelenamento linked talks about how a big, low-revving V8 could be more fuel-efficient despite having more displacement---lots of torque, low revs. The engine doesn't have to be a lot physically bigger, and if is stressed less, it doesn't have to be super-robust.

A slight wait increase and a significant efficiency increase sounds like a winner. One wonders though, how much torque would be too much, and how the rear tires would fare?

Another possibility would be a short-stroke V8, with the Hybrid motors doing all the low-end pulling, with the petrol motor almost free-wheeling, then using ther petrol motor gently for most of the lap and jamming it full on down the straights for a boost in top speed.

[Articus]

Originally Posted by avvelenamento

Coming back to who made what mood, the hybrid system of the 908 Hy4 was rumored to be a ferrari product. Such a shame that this great car never raced and now is disassembled somewhere inside peugeot sport HQ

Ferrari or Magneti Marelli?

[TF110]

Use a slow revving V8 coupled with the two hybrid powertrains, by the time the engine is all revved up, the hybrid power should be done. With 8mj of energy, if they use the current level of "300hp" of boost, it should last about 5-6 seconds. Currently the boost lasts 2-2.5 seconds.

[avvelenamento]

Originally Posted by TF110

Use a slow revving V8 coupled with the two hybrid powertrains, by the time the engine is all revved up, the hybrid power should be done. With 8mj of energy, if they use the current level of "300hp" of boost, it should last about 5-6 seconds. Currently the boost lasts 2-2.5 seconds.

a bit fictional, but it may work like this:
thermal engine revs to 4000-5000rpm developing not less than 550Nm to push the car out from a corner, during this is activated only the fron hybrid system giving the AWD effect to the car. Once reached this rev limiter, the flywheels turn off and the engine is set to come back to idle and the main rear hybrid system is activated powering the car until the next regenerative brake using the remaining of the 8MJ. During the acceleration the car is AWD with more than combined 800Nm pushing, then the final power (of course not the rumored 1100hp) is achieved with the only main rear hybrid system. The thermal engine should respect without problems the fuel flow. All this, however, can be done only if a single brake can charge the whole 8MJ capacity.

[avvelenamento]

i made a graph, a bit mess because is a tom's engine graph modified with paint, but should make understand what i mean.



Green is gasoline engine torque release, a peak of 550Nm close to 5000rpm, where it comes back in idle. Orange is the torque release of the front flying wheels, activated just to supply power togheter the gasoline engine, giving the 4x4 effect. Togheter should give a combined torque of more 850Nm. Once reached 5000rpm the main hybrid system is the only one to power the car. The torque release is still high, but being istantaneous, the bed decreases very fast giving to the car a final power not so different to the actual 550hp. Of course is just a theory.

[avvelenamento]

here is it a better graph (in the first one the torque of flywheels was too much high with a combined torque over 1000Nm). Sorry for the third post in a row, but it seems that the edit button is disable after a log out

[Maelochs]

Perfect illustration of the last paragraph of my post but developed even further. Interesting options.

[avvelenamento]

Thanks. If each regenerative brake can charge close to 8MJ, in my opinion this is the smartest way for gasoline engines to save fuel and have a more than decent power. Capacity is 8MJ, give 0.5MJ to each front wheel and 7MJ reserved to the main rear hybrid system and should be fine. A possible problem of this option could be the lenght of final electric boost, will be long enough to power the car during the long le mans straights?
A funny side-effect of this option would be to hear the noise of the car soon after a turn and seconds later the car becomes silent.
Anyway this almost confirms me that diesel engines will be advantaged again. For gasoline engines, engineers must to find and develope a lot of settings to optimize and make reliable the combined work of thermal and electric engines. For a diesel engine is simply enough to cut power burning less fuel to respect fuel flow, the low torque release will be however higher than the one developed by the gasoline engine, and active later the hybrid system to recover final power.