Mercedes Power Unit Hardware & Software

[Tommy Cookers]

the (fuel rate ex-tank) sensor is ultrasonic not magic

it is basically a sampling fuel velocity meter
it is cannot deal entirely with velocity variation across the pipe and variation from unsteady flow
it is only as good as allowed by its calibration on actual fuel and actual conditions

FIA rules allow (engine-cycle mean) fuel rates to exceed systematically the 100 kg/hr claimed
the fuel is compressed 4% at the injectors so is denser than the FIA says (due to the very high injection pressures)

[godlameroso]

It reminds me of phrenology in a sense, the FIA has some really precise tools but don't quite measure what they want to measure conceptually.

[roon]

The rules are very explicit about introducing anything post sensor. This would be a big big no no. Again a reach.

Which rule? The one you previously posted mentioned adulterating intake air, not fuel lines.

The sensor is Ultrasonic:

https://www.gillsc.com/products/flow-se ... w-meter-2/

http://www.racecar-engineering.com/tech ... ters-work/

Thanks for the links. It's tuned for:

Fuel compatibility Petroleum, diesel, bio fuels, race fuels ( LM24 petroleum,
LM24 diesel, F1 petroleum blends)

Not sure if one unit is universal to all these, or tuned per medium. Speed of sound through different fluids will vary, so adulteration of the fluid might vary how the sensor reads, depending on what's added; what I was getting at before. Not saying there's a benefit there specifically; was curious about sensor function.

The wording is new for 2018 and it is because of the Mercedes engines breather system.
As much as the "oil burn" stuff was exaggerated the only way they could control it differently in different sessions of the weekend was through the use of an Active control valve.

Why a need for control if it's an exaggeration? Why phrase it as "oil injection" if they're only trying to address actively valving breather gas ingestion? Oil mist in the breather gas?

[MrPotatoHead]

The rules are very explicit about introducing anything post sensor. This would be a big big no no. Again a reach.

Which rule? The one you previously posted mentioned adulterating intake air, not fuel lines.

The sensor is Ultrasonic:

https://www.gillsc.com/products/flow-se ... w-meter-2/

http://www.racecar-engineering.com/tech ... ters-work/

Thanks for the links. It's tuned for:

Fuel compatibility Petroleum, diesel, bio fuels, race fuels ( LM24 petroleum,
LM24 diesel, F1 petroleum blends)

Not sure if one unit is universal to all these, or tuned per medium. Speed of sound through different fluids will vary, so adulteration of the fluid might vary how the sensor reads, depending on what's added; what I was getting at before. Not saying there's a benefit there specifically; was curious about sensor function.

The wording is new for 2018 and it is because of the Mercedes engines breather system.
As much as the "oil burn" stuff was exaggerated the only way they could control it differently in different sessions of the weekend was through the use of an Active control valve.

Why a need for control if it's an exaggeration? Why phrase it as "oil injection" if they're only trying to address actively valving breather gas ingestion? Oil mist in the breather gas?

Because active control was an unintended loophole which they then closed.
You'll see in 2018 when power doesn't drop off and Mercedes still kick butt over a single lap in Q3 that the oil burn was overrated.

And you are correct the rules I quoted do not cover the fuel flow but it is very specific in the rules I'll find it if need be.

[stevesingo]

https://www.autosport.com/f1/news/13358 ... hp-barrier

[dren]

https://www.autosport.com/f1/news/13358 ... hp-barrier

Well, now we'll be right when we say Mercedes is the benchmark at 1000hp.

[digitalrurouni]

And what's crazy is there's only 3 engines for next seasons!!!

[OO7]

I wonder about the special modes that are used to achieve that output. 50% thermal efficiency (including power from the MGU-H in self-sustaining mode) is worth 831bhp. If the MGU-H is providing 100bhp, that leaves 60bhp from the ES making a total of 891bhp. Mercedes achieved 50%+ TE on the dyno earlier this year, but are yet to do so on track. The additional 100bhp (they say they are close to 1000bhp) must be born of methods that are not subject to efficiency constraints e.g oil burning (not to say oil burning is responsible for the significant power gains.)

[Just_a_fan]

And what's crazy is there's only 3 engines for next seasons!!!

Yes, but having an engine that needs to be able to do lots of races at high output means designing one that has even higher output on the dyno. It's debatable that we'll see a 3-engines-per-season engine giving 1000bhp on track next year. The question is how much will that 1000bhp engine give when run in 3-engines-per-season reliability mode?

The other question is: what are Ferrari getting out of their 3-engines-per-season engines on the dyno at the moment?

[PlatinumZealot]

I wonder about the special modes that are used to achieve that output. 50% thermal efficiency (including power from the MGU-H in self-sustaining mode) is worth 831bhp. If the MGU-H is providing 100bhp, that leaves 60bhp from the ES making a total of 891bhp. Mercedes achieved 50%+ TE on the dyno earlier this year, but are yet to do so on track. The additional 100bhp (they say they are close to 1000bhp) must be born of methods that are not subject to efficiency constraints e.g oil burning (not to say oil burning is responsible for the significant power gains.)

The power mode as you know is not the most efficient:
Use MGUH to power compressor.
Open wastegates to reduce turbine loading and back pressure
Disable all forms of battery charging.
Maximum MGUK output.

Work it backwards. 990bhp minus 160 mguk hp. Equals 830 ICE hp to the crankshaft in "Dyno queen mode" not actually sure if they ever achieve max power on the track though....

[dans79]

Work it backwards. 990bhp minus 160 mguk hp. Equals 830 ICE hp to the crankshaft in "Dyno queen mode" not actually sure if they ever achieve max power on the track though....

Probably not, but if you can achieve more on the dyno you can probably achieve more on the track.

[Juzh]

I wonder about the special modes that are used to achieve that output. 50% thermal efficiency (including power from the MGU-H in self-sustaining mode) is worth 831bhp. If the MGU-H is providing 100bhp, that leaves 60bhp from the ES making a total of 891bhp. Mercedes achieved 50%+ TE on the dyno earlier this year, but are yet to do so on track. The additional 100bhp (they say they are close to 1000bhp) must be born of methods that are not subject to efficiency constraints e.g oil burning (not to say oil burning is responsible for the significant power gains.)

The power mode as you know is not the most efficient:
Use MGUH to power compressor.
Open wastegates to reduce turbine loading and back pressure
Disable all forms of battery charging.
Maximum MGUK output.

Work it backwards. 990bhp minus 160 mguk hp. Equals 830 ICE hp to the crankshaft in "Dyno queen mode" not actually sure if they ever achieve max power on the track though....

While true, it almost never happens. ERS-K recovery is never fully disengaged. This can be seen quite easily on the ferrari steering wheel display because they have a very clear energy bar on the bottom, which always goes up a bit on braking events, including quali runs.

[digitalrurouni]

I honestly detest the 3 engine rule. There should be 5 engines allowed before penalties. I like seeing horsepower wars. I like seeing aero wars. I like seeing lap times get destroyed. I like seeing them go flat out more during the race. I don't like fuel saving. I would like to see cars going faster in the race so the 2 hour races get shorter and shorter because the cars are going even faster during the race. 3 engines means people turning down engines and all that rot. Ugh.

[MrPotatoHead]

I wonder about the special modes that are used to achieve that output. 50% thermal efficiency (including power from the MGU-H in self-sustaining mode) is worth 831bhp. If the MGU-H is providing 100bhp, that leaves 60bhp from the ES making a total of 891bhp. Mercedes achieved 50%+ TE on the dyno earlier this year, but are yet to do so on track. The additional 100bhp (they say they are close to 1000bhp) must be born of methods that are not subject to efficiency constraints e.g oil burning (not to say oil burning is responsible for the significant power gains.)

The power mode as you know is not the most efficient:
Use MGUH to power compressor.
Open wastegates to reduce turbine loading and back pressure
Disable all forms of battery charging.
Maximum MGUK output.

Work it backwards. 990bhp minus 160 mguk hp. Equals 830 ICE hp to the crankshaft in "Dyno queen mode" not actually sure if they ever achieve max power on the track though....

While true, it almost never happens. ERS-K recovery is never fully disengaged. This can be seen quite easily on the ferrari steering wheel display because they have a very clear energy bar on the bottom, which always goes up a bit on braking events, including quali runs.

That is because it is part of the braking system and it would be silly to not harvest energy under braking anyway as it is free from any negative consequences.

[godlameroso]

Only downside is rear brake bias and a propensity for entry lift off oversteer, as a negative torque is acting on the wheels . Granted mapping goes a long way in reducing this, for example a small amount of throttle(computer controlled) is used to nullify MGU-K negative torque, and give a more natural feeling, the downside being slightly higher fuel consumption.