roon wrote: ↑26 Aug 2019, 05:48
.....via abnormally high boost.....
henry wrote: ↑26 Aug 2019, 00:18
With turbines open the turbine still delivers power from blow down energy, bringing the compressor power up to the 100 plus kW needed.
I have another pet untested hypothesis that says a MGU-driven-compressor-speed turbine will create too much backpressure to permit exhaust flow through it during WGO.
doesn't the efficiency of the single stage compressor fall at 'abnormally' high boost ?
(isn't that what abnormally high boost is ?)
single stage supercharged aircraft (piston) engines at SL didn't exceed PR=2 and used less PR in sustained SL running
single stage compressor gas turbines similarly used rather low PRs in these situations ?
(I once booked to fly a Polish MiG 17)
what do actual compressor systems use ?
(NOTE to self - the only snippet I know reminds me of obligations via the Official Secrets Act)
PR improvement at an efficiency of c.80% became possible via research following the 70s energy crisis
PR=4 is available, even PR=5 at this efficiency
that's roughly how these F1 PUs can do what (we seem to believe at present) they do