Turbine powered MGU-K.

[RaptorHunter]

What would the advantages and disadvantages of having half a turbo (turbine without the compressor) to generate power to the MGU-K?

[NTS]

You would be very slow since the ICE would lose more than half of its power and the MGU-K power output is limited to what it is now by the rules. So the only thing you gain on the MGU-K side is more seconds of running per lap while you change your ICE into a much less powerful non-turbo 1.6 engine.

[RaptorHunter]

You would be very slow since the ICE would lose more than half of its power and the MGU-K power output is limited to what it is now by the rules. So the only thing you gain on the MGU-K side is more seconds of running per lap while you change your ICE into a much less powerful non-turbo 1.6 engine.

What about for other applications? Road cars, diesels. Is there any place where harvesting power from a exhaust driven turbine give benefits?

[gruntguru]

Yes. Its called turbo compounding. I saw a paper once on adding a turbine to a NA ICE.From memory there was a 7% power increase and slightly less fuel efficiency improvement.

Turbo compounding is usually done in conjunction with turbocharging because adding the turbine is the difficult part of turbocharging - it makes sense to finish off the job, add a compressor and reap further efficiency and power density benefits.

[wuzak]

A turbine powered MGUK would be the MGUH.

Porsche is using the system you describe for their LMP1. The turbo operates as normal, the exhaust from that and the bypass goes to a free power turbine which drives an MGU.

[bergie88]

This already happens in F1, combined with regenerative braking energy stored in the battery.

[Tommy Cookers]

What about for other applications? Road cars, diesels. Is there any place where harvesting power from a exhaust driven turbine give benefits?

turbo diesels of the usual design have little scope for this
they have little exhaust pressure energy left after driving the compressor
because they flow a lot more air relative to the fuel, so the compressor takes relatively more power
and because their cylinder expansion ratio is higher (a good thing), so their exhaust energy is relatively low anyway

road SI engines would only benefit at high power (WOT)
the other 99% of the time they are throttled and the cylinder pressure and exhaust pressure are low
typically recovery would be 2-4%
SI engines are driven essentially by degrading the efficiency by throttling
improving efficiency by exhaust recovery (compounding) would be pointless
because the driver would then have to throttle more (closed) to hold the required speed

F1 has the compressor linked to the turbine, this is road relevant (eliminating lag)
F1 people might prefer having one turbine driving only the compressor and another driving only the generator
as allowed in endurance racing
F1 drivers had no problem driving around turbo lag, certainly in the later, lower boost 80s F1

[turbof1]

Like has been mentioned, this already being done in the form of the mgu-h.

This is more efficient then storing and taking energy on/from the battery. There's no transformation from AC to DC involved, which lowers the efficiency.

Note that the mgu-h actually works in the form of a waste gate. So the turbo keeps delivering to the ICE until it hits the 125.000rpm limit, at which excess heat gets converted to electric energy. So it might not be completely what you had in mind.

[trinidefender]

Like has been mentioned, this already being done in the form of the mgu-h.

This is more efficient then storing and taking energy on/from the battery. There's no transformation from AC to DC involved, which lowers the efficiency.

Note that the mgu-h actually works in the form of a waste gate. So the turbo keeps delivering to the ICE until it hits the 125.000rpm limit, at which excess heat gets converted to electric energy. So it might not be completely what you had in mind.

The MGU-k is an AC motor/generator unit. That means that you need something controlling the frequency of the power going to the MGU-K. I believe the same goes for the MGU-H some efficiency is lost in this process.