russ@crlt.UUCP (10/29/87)
In article <9298@tekecs.TEK.COM>, philb@maya.gwd.tek.com (Phil Biehl) writes: >In <5270001@hpisof0.HP.COM> campbelr@hpisof0.HP.COM (Bob Campbell) writes: >>Flowrates: >> Hydrogen 160 lb/s 16,436 gpm >> Oxygen 970 lb/s 6,121 gpm > >Does the above flowrates indicate tha actual combustion mixture present at the >combustion chamber? If so then why is there a greater ratio than 2 parts H to >one part O? I would think that the extra hydrogen would be unconsumed making >the engine less efficient than it could be... What am I missing? Nothing. The SSME operates on a very rich mixture in order to keep a reducing atmosphere in the engine (otherwise metals burn), cool the exhaust (turning energy which would otherwise escape in the form of excited molecules into heat, which helps the impulse) and reduce the molecular weight of the exhaust (to increase its velocity and thus impulse). If a more efficient engine could be built using a stoichiometric mixture, NASA would have tried to do it; the SSME specs say they sure went all-out this time. (These facts gleaned from various lectures by Jim Loudon and other sources.) -- The above are the official opinions and figures of Robust Software, Inc. Forewarned is half an octopus. Russ Cage, Robust Software Inc. ihnp4!itivax![m-net!rsi,crlt!russ]