noname wrote:You will need some kind of energy storage device to "stabilize" the system. Even if you would like to put the energy directly to the wheels.
You will not extract power all the time, it will not be continues 120kW, DC may not be 100%, etc. And, afetr all, MGU stands for Motor Generator Unit, so it is supposed to extract the power from the exhaust gases, but also to spin up the turbo (i.e. to improve transients).
AFAIK the MGUH will mainly operate in generator mode except for spool up when there is the option to avoid the turbo lag by letting it suck energy from the battery and work in motor mode. I expect this to be the big exception. Under standard conditions there will be a surplus of enthalpy from the waste gas which can be used to drive the MGUK in motor mode.
I don't agree that the electric power from the MGUH has to be fed to a battery between the MGUH and the MGUK. Both units are fitted with a power electronic inverter which modulates the AC power to fit the unit characteristic. This technology is also used in multi axis machine tools. You typically find an intermediate circuit capacitor in such designs to do that job. I fully expect F1 to adopt that design. The electric conversion losses are much smaller compared to a battery.
Regarding the efficiency of the turbine and the compressor the rules are very free. For typical axial units as they are used in contemporary turbochargers you would expect 70%+ efficiency. Because F1 can afford to throw some money at higher efficiency I would expect the designers to use radial flow at least for the turbine which is probably transforming twice as much power as the compressor on average.
If I remember right an estimation of the total turbine power in one of the old threads came to 140 kW. After transformation losses for the turbine, the MGUH and the compressor that would probably be 100 kW net power. And the split could have been 40 kW to the compressor and 60 kW to the rear wheels. Don't nail me on the figures. They come from memory. It would be better for someone to check the old 2010 thread on the 2013 turbo unit.
Edit: found the thread viewtopic.php?p=200560#p200560
The estimated efficiencies fit, but the net power output is considered close to 200 kW. The thermodynamic computations were done by Ringo. Perhaps he can adapt the 2010 assumptions - which were done for a four cylinder engine with different fuel limit - to the current data. I expect a net value below the 200 kW.
The interesting result from the thermodynamic computation is the ratio between the turbine and the compressor power and the efficiencies, which I expect to be similar for the 2014 system. The compressor is only using 37% of the total enthalpy that the turbine is converting to power. The compressor is estimated at 76% efficiency and the turbine at 85%.