Mercedes Power Unit Hardware & Software

All that has to do with the power train, gearbox, clutch, fuels and lubricants, etc. Generally the mechanical side of Formula One.
ispano6
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Re: Mercedes Power Unit Hardware & Software

Post by ispano6 » Tue Jun 25, 2019 12:14 am

Seems like during this past race Mercedes had a bit more "additive" burning "smoke" noted during the formation lap. Is this the case or has it not really changed so much this season?

roon
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Re: Mercedes Power Unit Hardware & Software

Post by roon » Tue Jun 25, 2019 1:09 am

Out of the engine exhaust or the breather pipe? They are sometimes right next to each other.

ispano6
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Re: Mercedes Power Unit Hardware & Software

Post by ispano6 » Tue Jun 25, 2019 8:10 pm

Please forgive me if this has already been posted, but I found this not only insightful to me, but rather surprising in Mercedes AMG HPP's openness in depicting what makes up the current winning formula.
https://www.mercedes-amg-hpp.com/formul ... ine-facts/
Updated: Apologies it seems to be old, refers to Nico.
Last edited by ispano6 on Tue Jun 25, 2019 8:16 pm, edited 2 times in total.

PlatinumZealot
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Re: Mercedes Power Unit Hardware & Software

Post by PlatinumZealot » Tue Jun 25, 2019 8:14 pm

Its a red herring. Nothing no other teams don't know.
"The true champions are also great men. They are capable of making difficult decisions, of admitting their mistakes and of pushing harder than before when they get up from a fall."

- Ferrari chairman Sergio Marchionne

roon
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Re: Mercedes Power Unit Hardware & Software

Post by roon » Sun Jul 07, 2019 6:36 am

Regarding overheating in Austria: was this a reference to engine water temperature, electrical device water temperature, oil temperature, or charge air temperature? Or some combination of the aformentioned, potentially?

Might also be related to CC temperatures. Lower RPM peak power may be, for example, more efficient but harder upon componentry. Shifting the powerband up could relieve the crankshaft, pistons, conrods, and journals via reduced peak cylinder pressures and temperatures. Shifting it down may increase combustion efficiency and power but may be more reliant upon water and oil cooling of the combustion chamber.

If oil temperatures could not be reduced via the heat exchangers sufficiently, then sufficient control of piston crown temperature might also be lost, forcing the use of engine modes that shift the powerband higher. I'm reminded of the advantages of steel piston crowns in this context.

If not crown temperature related, maybe they were at the edge of their oil's operating temperature i.e. higher power engine modes rely upon oil properties which might be lost above a threshold temperature.

If not ICE related, could be that they were preserving the ES or the electric motors. They were lifting at the end of straights, which might suggest the issue was not on the electrical side of the powertrain.

If it is charge air cooling related, this may be the long tail of engine oil regulations changes. Recall that this is only the second season where oil composition and consumption are explicitly defined. It was essentially confirmed by the 2018 regulations that at least someone was using octane boosting compounds that could be boiled out of engine oil above 210°C. If charge temperatures rise, an octane boosting oil might have been what prevented detonation in previous seasons. Now they may be left with altering other parameters which in turn reduce power output.

izzy
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Re: Mercedes Power Unit Hardware & Software

Post by izzy » Sun Jul 07, 2019 11:34 am

roon wrote:
Sun Jul 07, 2019 6:36 am
Regarding overheating in Austria: was this a reference to engine water temperature, electrical device water temperature, oil temperature, or charge air temperature? Or some combination of the aformentioned, potentially?

Might also be related to CC temperatures. Lower RPM peak power may be, for example, more efficient but harder upon componentry. Shifting the powerband up could relieve the crankshaft, pistons, conrods, and journals via reduced peak cylinder pressures and temperatures. Shifting it down may increase combustion efficiency and power but may be more reliant upon water and oil cooling of the combustion chamber.

If oil temperatures could not be reduced via the heat exchangers sufficiently, then sufficient control of piston crown temperature might also be lost, forcing the use of engine modes that shift the powerband higher. I'm reminded of the advantages of steel piston crowns in this context.

If not crown temperature related, maybe they were at the edge of their oil's operating temperature i.e. higher power engine modes rely upon oil properties which might be lost above a threshold temperature.

If not ICE related, could be that they were preserving the ES or the electric motors. They were lifting at the end of straights, which might suggest the issue was not on the electrical side of the powertrain.

If it is charge air cooling related, this may be the long tail of engine oil regulations changes. Recall that this is only the second season where oil composition and consumption are explicitly defined. It was essentially confirmed by the 2018 regulations that at least someone was using octane boosting compounds that could be boiled out of engine oil above 210°C. If charge temperatures rise, an octane boosting oil might have been what prevented detonation in previous seasons. Now they may be left with altering other parameters which in turn reduce power output.
it's a fun thing to speculate. Martin Brundle mentioned 30 radiators in some cars, presumably each of them has a calculation, of joules dissipated with its airflow of velocity X and air density, humidity and temperature and they were pretty much all out of specification in Austria, all the same, otherwise some were over-specified weren't they. Tho there's a question of how much cooling is done in a shared way with the same coolant so if they can reduce one item in the chain it helps the others

and now there must be teams of engineers slaving away trying to dissipate more joules without messing up the aero, with coatings, textures, the fluid (is there anything better than water?) the ducting and every single little thing. Oil isn't a great coolant is it perhaps they're on at Petronas too. Wish they'd tell us more about it, i bet the other teams have plenty of ex-Mercedes staff telling them!

Anyway if they're 'only' 3rd and 5th in Austria and Mexico that's still a great car over the season. Hungary I suppose.

PlatinumZealot
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Re: Mercedes Power Unit Hardware & Software

Post by PlatinumZealot » Wed Jul 17, 2019 3:30 am

The car was designed with smaller and more closely packed radiators. So it is inherently weaker on average engine power at some circuits. They can still modify according to circuit if they wished... But they want to stick to this downforce philosophy.
"The true champions are also great men. They are capable of making difficult decisions, of admitting their mistakes and of pushing harder than before when they get up from a fall."

- Ferrari chairman Sergio Marchionne

digitalrurouni
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Re: Mercedes Power Unit Hardware & Software

Post by digitalrurouni » Wed Jul 17, 2019 4:56 pm

Could explain why the Mercedes is slower at Mexico then as well. High altitude. Can't get rid of the heat.

ENGINE TUNER
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Re: Mercedes Power Unit Hardware & Software

Post by ENGINE TUNER » Wed Jul 17, 2019 5:38 pm

digitalrurouni wrote:
Wed Jul 17, 2019 4:56 pm
Could explain why the Mercedes is slower at Mexico then as well. High altitude. Can't get rid of the heat.
That, but also their max downforce aero package hasn't been as good as RBR in recent years so the tires struggled because of more sliding.

roon
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Re: Mercedes Power Unit Hardware & Software

Post by roon » Tue Jul 23, 2019 6:38 pm

It would appear the compressor inlet stator vanes can be used as a throttle. If so, for what use?

Throttling the compressor might reduce MGUH power requirements for spool up.
Last edited by roon on Tue Jul 23, 2019 7:23 pm, edited 1 time in total.

subcritical71
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Re: Mercedes Power Unit Hardware & Software

Post by subcritical71 » Tue Jul 23, 2019 6:55 pm

roon wrote:
Tue Jul 23, 2019 6:38 pm
It would appear the compressor inlet stator vanes can be used as a throttle. If so, for what use?
On axial flow compressors the VSV are used to avoid operating on the wrong side of the compressors surge line. Are turbos susceptible to surge? If so, with the potential variable speeds of the F1 turbo could this be used as a similar function? Or, a way to keep the compressor at its optimal setting over a wide range of variable ICE intake air requirements.

Pyrone89
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Re: Mercedes Power Unit Hardware & Software

Post by Pyrone89 » Tue Jul 23, 2019 7:04 pm

Cooling bullet dodged, Sunday is forecasted to be only 25 degrees and even rainy. Will have to wait for Hungary to see if the rumored cooling fix works.

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Re: Mercedes Power Unit Hardware & Software

Post by Mudflap » Tue Jul 23, 2019 10:41 pm

roon wrote:
Tue Jul 23, 2019 6:38 pm
It would appear the compressor inlet stator vanes can be used as a throttle. If so, for what use?

Throttling the compressor might reduce MGUH power requirements for spool up.
They are there strictly to provide pre-whirl at part load.
How much TQ does it make though?

ENGINE TUNER
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Re: Mercedes Power Unit Hardware & Software

Post by ENGINE TUNER » Tue Jul 23, 2019 11:10 pm

Pyrone89 wrote:
Tue Jul 23, 2019 7:04 pm
Cooling bullet dodged, Sunday is forecasted to be only 25 degrees and even rainy. Will have to wait for Hungary to see if the rumored cooling fix works.
Canada, France and Silverstone were hot, Merc had cooling problems in Austria because of the combination of high ambient temperatures and also the high altitude. Hockenheim is not high altitude, so regardless of the temperature, Merc were going to be ok.

roon
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Re: Mercedes Power Unit Hardware & Software

Post by roon » Tue Jul 23, 2019 11:28 pm

Mudflap wrote:
Tue Jul 23, 2019 10:41 pm
roon wrote:
Tue Jul 23, 2019 6:38 pm
It would appear the compressor inlet stator vanes can be used as a throttle. If so, for what use?

Throttling the compressor might reduce MGUH power requirements for spool up.
They are there strictly to provide pre-whirl at part load.
They appear to be capable of fully shuttering closed. Which implies function beyond inducing helicity.