" From: Ken Ames <ameskg@xxxxxxxxx> " " " Quoting farna@xxxxxxx: " " > Tom, that would be APU (auxilliary power unit). They are used in aircraft " > (including larger helicopters) to provide starting power and ground power in " > remote locations or for short periods. I've seen a few. They produce hp at " " > very high rpm as Andrew pointed out -- no useable torque, and a very narrow " -------------- " On the contrary, turbines are like steam engines, lots of torque and it starts " at zero rpm. " http://www.motortrend.com/classic/features/c12_0603_1964_chrysler_turbine_car/specifications.html this must be a free turbine design, with the output shaft driven separately from the compressor. it is obviously possible to design it to give torque at zero output rpm, but like a torque converter - which it is, in a way - at a penalty. you have to trade efficiency for this sort of flexibility. " > power band. I think his electric idea has merit, but I think you'd still need " > a battery to control the power between the gen and motor -- or a very large " > variable resistance to dump excess power! On second thought, there should be " > an electrical way to vary generator output without varying engine speed " > much... i was thinking of a permanent-magnet alternator, brute-force controlled by an scr output bridge - but if it has a wound field it can be controlled the same way a car alternator is, via the field current. i didn't think slip rings at tens of thousands of rpm was a good idea though. " _______________________________________________ " From: "Swygert, Francis G MSgt 436 CES/CECM" <Francis.Swygert3@xxxxxxxxxxxx> " " I looked at the site. It's obvious you can't have ANY torque at ZERO " rpm!! it -is- possible! notice they mentioned an auto transmission -without- torque converter -- the output turbine, on its own shaft, must have this function. the compressor shaft would still have to be spinning at its usual speed. ________________________________________________________________________ Andrew Hay the genius nature internet rambler is to see what all have seen adh@xxxxxxxxxxxxxxxxx and think what none thought _______________________________________________ AMC-List mailing list AMC-List@xxxxxxxxxxxx http://www.amc-list.com/mailman/listinfo/amc-list or go to http://www.amc-list.com