This sounds very much like "stratified charge" which can reduce pumping

losses much like
a "Diesel" . However, direct injection runs into the same mixing limits as a
"Diesel"
which can limit full power output levels. I think the last time I looked at
Mercury
data the direct injection engines were rated lower HP than the port injected
same
model. Direct injection can be a double edged sword in this way - it
improves effective
volumetric air efficiency - particularly when compared to vaporized fuel
mixtures,
but makes uniform distribution for high power output more difficult. - Vance

Vance, I believe your partially correct here, the Mercury direct injection engines may show a small power loss. I think that the loss is explainable as the losses needed to drive the direct injection pump! I am NOT a big proponent of stratified charge system but in an unusual chamber like the rotary some stratification of the charge is probably helpful. My interest in the direct injection for the rotary is that it fixes two big problems. First; the manifold is simpler, and if you are running no air filter then alternate air isn't needed. Second; direct injection will give excellent mixture control while also keeping the high pressure fuel as far from the exhaust as possible. Lastly, inkeeping with the discussion about octane levels, multi-fuel capability is a possiblity, which helps us market the rotary to the avation community more easily. (Mistral is way ahead on this with their heavy fuel version of the engine)
Bill Jepson

 
The Rotary Engine NewsLetter.  Powered by Linux.
ACRE NL web site. http://home.earthlink.net/~rotaryeng/            
Copyright 1998-2004 All world wide rights reserved.