Mercedes-AMG F1 W10 EQ Power+

[SiLo]

These pu units have a thermal efficiency of 50% they is another 50 to go hardly a dead end.maybe Mercedes are finding it hard to find extra power without dodgy oil burning what's funny was Ferrari was supposed to be the cheating one with smoke bellowing out of the exhaust when ever they leave the pit and extra sensors they were carrying.

Advances in that regard are going to be few and far between. These are already the most thermally efficient internal combustion engines in the world. And the most efficient engine in the world is a combined cycle power plant, which reaches around 60%. So unless they want to have two engines in the back, I doubt it's going to get much higher.

[KiLLu12258]

In the post-race press conference, Lewis said, I quote: ..."I think we’ve got some improvements to try to make to the car within four days ..." so they have something special for this race, presumably aero I think ...

Then, Toto said the 2 PU failures forced to run them in the race in a conservative mode, without the highest race PU mappings ... that`s the second statement on this matter and could be one reason behind that 15km/h deficit to Ferrari on the straights at Spa ...

To me that Merc has other philosophy than Ferrari when they introduce a new spec: they - both customers and works team - just run them in a lower PU mode (or better say not in the highest PU modes) in order to have some real track data but most of all to calibrate them fully at the next race, which by the way is Monza ... Ferrari is even more conservative on this matter and just lets the customer's teams be their "guinea pig tests" and do this pre-phase of new spec PU introduction ...

It seems that Merc has just arrived at a dead-end regarding their PU "architecture" philosophy and must focus in the future to those areas which Ferrari has outperformed them: combustion and MGU-H ...

On another note, how much time the PU manufacturers do they take in R&D + dyno tests prior they run a new PU spec? I`ve read somewhere they need at least 6 months in advance ... so for this 3rd spec. 2019 PU they were starting way back at the beginning of the springtime ... and they are now working for the first 2020 PU spec. it seems ...

probably we dont know how much the advantage of the ferrari pu really is as its not clear how much difference the downforce or the general drag at the straights make.I think this is the bigger point at all.
What i dont get is, why mercedes cant use a wing like redbull do for years, which is a lot smaller - this should give a lot topspeed or i am wrong?

[mkay]

It seems that Merc has just arrived at a dead-end regarding their PU "architecture" philosophy and must focus in the future to those areas which Ferrari has outperformed them: combustion and MGU-H ...

Rumour is that Merc will introduce significant ICE-focused improvements next year, for the first time since those PU have been operational.

[SiLo]

It seems that Merc has just arrived at a dead-end regarding their PU "architecture" philosophy and must focus in the future to those areas which Ferrari has outperformed them: combustion and MGU-H ...

Rumour is that Merc will introduce significant ICE-focused improvements next year, for the first time since those PU have been operational.

Does this mean new architecture or new manufacturing methods?

[subcritical71]

Advances in that regard are going to be few and far between. These are already the most thermally efficient internal combustion engines in the world. And the most efficient engine in the world is a combined cycle power plant, which reaches around 60%. So unless they want to have two engines in the back, I doubt it's going to get much higher.

Just a minor note, and don't take this negatively, but a gas turbine is still an ICE. So the most thermally efficient ICE is a gas turbine (in combined cycle mode as you mentioned). The distinction I think you were going for is reciprocating vs rotary internal combustion engines.

[PhillipM]

That efficiency wall however, doesn't stop you getting more power from using 100% fuel flow all the time and using storage and deployment tricks through cycling the MGU-H, instead of fuel saving at some portions of the race.
Does come with the downside of having to carry more fuel or run a lower power modes for the race though - I think that's where Ferrari is getting their straightline boosts from - not the top speed, that's aero efficiency, but they have a notable boost in acceleration compared to the Merc as soon as the car isn't traction limited.
Whether that's from the trick battery setup or something more simple like a weighted turbo (they do take noticably longer to spool up out of the garage than anyone else), I'm not sure.

[SiLo]

That efficiency wall however, doesn't stop you getting more power from using 100% fuel flow all the time and using storage and deployment tricks through cycling the MGU-H, instead of fuel saving at some portions of the race.
Does come with the downside of having to carry more fuel or run a lower power modes for the race though - I think that's where Ferrari is getting their straightline boosts from - not the top speed, that's aero efficiency, but they have a notable boost in acceleration compared to the Merc as soon as the car isn't traction limited.
Whether that's from the trick battery setup or something more simple like a weighted turbo (they do take noticably longer to spool up out of the garage than anyone else), I'm not sure.

How does more inertia in the turbine help make more mid-range acceleration?

[PhillipM]

over-spool the turbine when you're traction limited through the corner and then dump power from it to the K when you're not.

[henry]

over-spool the turbine when you're traction limited through the corner and then dump power from it to the K when you're not.

The inertia of the turbo/H assembly is quite small. I have used 6.4E-04kgm^2 in the past, an Italian paper looking at lag control used 5.6E-04. When looking at Honda’s extra-harvest I found 120kW for 25msec changed the assembly speed by 6000rpm.

When traction is no longer limited the max power is fixed at ICE(wastegate open) + 120kW, so if your theory holds the effect would be to extend the duration of ICE(wastegate open). That extension depends on the inertia and over speed. Assuming the inertia doubles and the over speed is 24k that would give 0.2seconds extra. Of course that would come at the expense of extra energy consumption from the ES for lag control, and that would reduce the duration the overspool would allow.

[Morteza]

Via AMuS

[PhillipM]

over-spool the turbine when you're traction limited through the corner and then dump power from it to the K when you're not.

The inertia of the turbo/H assembly is quite small. I have used 6.4E-04kgm^2 in the past, an Italian paper looking at lag control used 5.6E-04. When looking at Honda’s extra-harvest I found 120kW for 25msec changed the assembly speed by 6000rpm.

When traction is no longer limited the max power is fixed at ICE(wastegate open) + 120kW, so if your theory holds the effect would be to extend the duration of ICE(wastegate open). That extension depends on the inertia and over speed. Assuming the inertia doubles and the over speed is 24k that would give 0.2seconds extra. Of course that would come at the expense of extra energy consumption from the ES for lag control, and that would reduce the duration the overspool would allow.

Which is why I said they may deliberately weight the turbo

[henry]

over-spool the turbine when you're traction limited through the corner and then dump power from it to the K when you're not.

The inertia of the turbo/H assembly is quite small. I have used 6.4E-04kgm^2 in the past, an Italian paper looking at lag control used 5.6E-04. When looking at Honda’s extra-harvest I found 120kW for 25msec changed the assembly speed by 6000rpm.

When traction is no longer limited the max power is fixed at ICE(wastegate open) + 120kW, so if your theory holds the effect would be to extend the duration of ICE(wastegate open). That extension depends on the inertia and over speed. Assuming the inertia doubles and the over speed is 24k that would give 0.2seconds extra. Of course that would come at the expense of extra energy consumption from the ES for lag control, and that would reduce the duration the overspool would allow.

Which is why I said they may deliberately weight the turbo

There are some flaws in my reasoning.

If the utility is in electric supercharge mode the assembly inertia also has to drive the compressor. That would reduce the duration to around 0.12 seconds. And of course the benefit only comes from the increase in inertia, so now the extra deployment duration would be 0.06 seconds. This additional deployment would be in electric supercharge mode so the benefit is the additional ICE power, say 20 to 30kW.

I’m not sure that 30kW for an extra 0.06 seconds would make the sort of difference that is reported between Mercedes and Ferrari.

Edit: an even deeper flaw. The energy to over spin the turbo could have gone to the ES. The turbo assembly is an alternative not additional energy store. The only difference is that in this use case the turbo will be more efficient. Now we’re down to milliseconds of extra deployment offset by extra anti lag duty. I’m satisfied that heavy turbos are not a thing.

Sorry for the off topic.

[zibby43]

"After the PU problems at Spa, Mercedes arrives in Monza as it left Spa. There are still questions about reliability. The checks at Brixworth are ongoing as the engineers are still trying to understand the causes of the failures. Merc is waiting as long as possible to decide whether to run the engines at full power in Monza."

https://twitter.com/SmilexTech/status/1 ... 83329?s=20

[mkay]

"After the PU problems at Spa, Mercedes arrives in Monza as it left Spa. There are still questions about reliability. The checks at Brixworth are ongoing as the engineers are still trying to understand the causes of the failures. Merc is waiting as long as possible to decide whether to run the engines at full power in Monza."

https://twitter.com/SmilexTech/status/1 ... 83329?s=20

Disappointed that they haven't been able to figure things out in the past 72 hours post-race, but they still have a few more days.

They may be getting lucky with the latest forecasts showing potential rain or damp track on race day.

[Just_a_fan]

They may get a phone call during qualifying or even during he race saying "we know what the problem is, turn up the engines". That would be fun - lap 15 and suddenly the Mercs find 0.5 second a lap extra pace to chase whomever is in front.