wuzak wrote:And considering that the FIA and the engine manufacturers set out to match the V8 output (~750hp) with the new engine (ICE + MGU-K), it would be unlikely that the power is <<600hp.
Sensible assumption!
I would just add, that in theorized stage the FIA along with consulted manufacturers may have overestimated and missed the power targets due to many technical unknowns they were embarking upon
wuzak wrote:If we take the Cosworth curves, at 12k rpm the BSFC is ~240g/kW/hr in ICE only mode, ~190g/kW/Hr in ICE + MGU-H and ~180g/kW/hr in ICE + MGU-K.
In my view it is foolish to take those "Cosworth curves" seriously, since they are not based on fact, but are the results of assumptions. stipulations and a lot of fudgy wishful thinking.
wuzak wrote:
Assuming a LHV for the fuel of 45MJ/kg, that works out to be 33%, 42% and 44% efficiencies respectively.
In power terms, that works out to 558hp, 706hp anf 744hp. At 12,000rpm.
You are getting closer, however the 558HP figure is still "out on the limb" in my view.
wuzak wrote: At 10,500rpm, the BSFC are ~230g/kW/hr, ~195g/kW/hr and ~175g/kW/hr. Efficiencies are 35%, 41% and 45%. Power is ~583hp, ~687hp and ~766hp. Note that in compounded mode - the mode they will be in most of the time when traction i sup to it - the engine is more efficient at 12k rpm than at 10.5k rpm.
Also, from a practical point of view, as pointed out by others above, power falls off dramatically below 10,500rpm. Gear changes will want to drop the rpm to 10,500rpm, not below. Again, only in traction limited situations will it be different.
When reviewing SAE paper on Honda 1.5T F1 engine key performance factors become evident.
Firstly the calculated BMEP at full power is 32.5 bar, which indicates a certain boundary to combustion in view of the knock limit permitted by the fuel.
If we assume the figures that you quote of 558HP and I would urge to accept 10500 RPM as real engineering target for this power peak, then we get the following.
RPM - 10500
Power - 558HP
Torque @ pwr peak - 279 lb-ft
BMEP - 29.7 bar
What we see in this scenario, is that the 1.6L turbo engine while running at it's limited fuel rate is still quite easily falling within the rough boundaries of thermodynamic capability. Meaning, that this engine can easily "use up" the chemical energy potential offered by the fuel and DOES NOT need to be run any higher than 10500 RPM. At RPM higher than 10500, this engine will make less and less power proportionally to internal friction increase.
My next question is whether this 558HP is possible from 100kg/hr of fuel flow?
That works out to 240 g/kW-hr or 0.395 lb/HP-hr
In my view that is very optimistic result.