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wuzak wrote:So, you are suggesting 720hp using 43MJ/kg fuel?
In compounding mode only?

Something like that.
Not sure what you mean by compounding mode. For me (and no doubt the engineers at Merces, renault, Ferrari and Honda) any claims about ICE efficiency would relate to the power produced on the dynamometer. That would include crankshaft power plus MGUH power - with no ES, no MGUK etc etc anywhere in sight.

gruntguru wrote:

wuzak wrote:So, you are suggesting 720hp using 43MJ/kg fuel?
In compounding mode only?

Something like that.
Not sure what you mean by compounding mode. For me (and no doubt the engineers at Merces, renault, Ferrari and Honda) any claims about ICE efficiency would relate to the power produced on the dynamometer. That would include crankshaft power plus MGUH power - with no ES, no MGUK etc etc anywhere in sight.

What I meant by compounding mode is that the MGUH supplies power directly to the MGUK and no energy is taken from storage (ES). As you have described.

The suggestions I have seen on the power developed with the MGUK at full output (120kW) is around the 850hp mark. Which would suggest 690hp without the MGUK. And around 790-800hp in self sustaining mode.

That suggests much higher TE.
45% TE = 720 bhp (@43 MJ/kg)
800 bhp = 50% TE

690 bhp = 43% TE (which is close to Toyota's claim for a turbocharged engine with no compounding.)

gruntguru wrote:That suggests much higher TE.
45% TE = 720 bhp (@43 MJ/kg)
800 bhp = 50% TE

690 bhp = 43% TE (which is close to Toyota's claim for a turbocharged engine with no compounding.)

A while ago Mercedes stated they were close to 1000bhp with the current engine formula?

Blaze1 wrote:

gruntguru wrote:That suggests much higher TE.
45% TE = 720 bhp (@43 MJ/kg)
800 bhp = 50% TE

690 bhp = 43% TE (which is close to Toyota's claim for a turbocharged engine with no compounding.)

A while ago Mercedes stated they were close to 1000bhp with the current engine formula?

They stated they would reach 1000 bhp within a few years, so I would not be surprised if they are between 900 and 950 bhp at this moment, with Ferrari not far behind.

About the TE together with compounding, gruntguru stated some posts ago that compounding is worth about 3-4% of TE. But when compounding is providing around 90kW of power, isn't this number much higher then? Assumption: When 650 bhp equals 40% TE, then 120 bhp of turbo compounding equals around 6% of TE. Adding this to the numbers of Toyota (which could even be higher in F1 nowadays according to the reasons of gruntguru), the 50% TE comes in sight

Blaze1 wrote:

gruntguru wrote:That suggests much higher TE.
45% TE = 720 bhp (@43 MJ/kg)
800 bhp = 50% TE

690 bhp = 43% TE (which is close to Toyota's claim for a turbocharged engine with no compounding.)

A while ago Mercedes stated they were close to 1000bhp with the current engine formula?

Is that a statement, or a question?

Perhaps such blanket claims ( if actually made) were based on telemetry extrapolation rather than dyno readings..

I wonder what a realistic number for MJ/kg of the Petronas or Shell gasoline, more than 45?

J.A.W. wrote:

Blaze1 wrote:

gruntguru wrote:That suggests much higher TE.
45% TE = 720 bhp (@43 MJ/kg)
800 bhp = 50% TE

690 bhp = 43% TE (which is close to Toyota's claim for a turbocharged engine with no compounding.)

A while ago Mercedes stated they were close to 1000bhp with the current engine formula?

Is that a statement, or a question?

Perhaps such blanket claims ( if actually made) were based on telemetry extrapolation rather than dyno readings..

It was more of a question, that Mercedes have stated (Toto Wolff) they are no far off 1000bhp and that such a figure would be attainable soon as bergie88 remembered. While we don't have official figures, such a statement would lead me to believe a current output of over 850bhp. So I was seeking an explanation of the differences between Mercedes comments and the power figures suggesting less than 800bhp.

Ifyou go back to Wuzak's post where he says The suggestions I have seen on the power developed with the MGUK at full output (120kW) is around the 850hp mark. Which would suggest 690hp without the MGUK. And around 790-800hp in self sustaining mode.

So 850 is probably a realistic number. Add to that perhaps 50 hp in "qualy mode" where the ES is driving both the MGUK and the supercharger (via MGUH) allowing the wastegate to be open and zero exhasut backpressure on the engine.

In one sense the MGUH is actually driving the crankshaft in "qualy mode" - powering the supercharger which in turn pushes down on the pistons during the intake stroke (the more boost the better in this mode) without the parasitic pressure normally applied to the pistons during the exhaust stroke.

Just how will conditions for the ICE be different from "qualifying " to "race-mode" isn't the fuel-flow the same, do explain?

Sixbarboost wrote:Just how will conditions for the ICE be different from "qualifying " to "race-mode" isn't the fuel-flow the same, do explain?

Yes, the maximum allowed fuel flow is the same. The difference is that during qualifying the battery can be fully depleted during one lap, while during the race the battery level at the end of one lap should be the same as at the begin of the lap (charge-sustaining). This means in simple terms that more energy is available during qualifying.

More thn once it is explained in the former posts.

This "quali mode" means that the ES is powering the MGU-K (120 kW) PLUS the MGU-H (maybe 45 kW ??).
So there is no backpressure built up to drive the turbo, which will result in more ICE power.
Of course 100kg/s is still the limit.

You can make a quick calculation about how long such a quali mode can be used before depletung the battery.
This is by no means sustainable.

gruntguru wrote: ...... in "qualy mode" where the ES is driving both the MGUK and the supercharger (via MGUH) allowing the wastegate to be open and zero exhasut backpressure on the engine.
In one sense the MGUH is actually driving the crankshaft in "qualy mode" - powering the supercharger which in turn pushes down on the pistons during the intake stroke (the more boost the better in this mode) without the parasitic pressure normally applied to the pistons during the exhaust stroke.

'the more boost the better' ..... in qualy mode ?
because there's no back pressure, won't the boost needed for a given air massflow be lower ?

how about running the ICE (part-wastegated?) as a turbocharged engine only ? - this also lowers the backpressure
(combining this with 120 kW motoring from the mgu-k and ES of course)

Stupid question I know, but how can the PU's power possibly ever be more than 100kg/h times efficiency plus 120 kW?

Sixbarboost wrote:Stupid question I know, but how can the PU's power possibly ever be more than 100kg/h times efficiency plus 120 kW?

It cannot.

You'll have to use up ES energy to boost power in the described mode.