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Reciprocating piston engines generally use a richer fuel mixture under
high speed and high-load conditions to prevent knocking. In contrast, rotary
engines do not require a particularly rich fuel mixture under these
conditions due to their special
combustion characteristics. In addition, the RENESIS achieves nearly
complete combustion over the entire speed range thanks to its high
compression ratio and the use of new fuel injectors designed for improved
fuel atomization. These enhancements allow the RENESIS to run on a leaner
fuel mixture than conventional rotary engines from the low to the high-rev
range. The result is the power and performance of a sports car engine and
reduced fuel consumption. Low Emissions
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Instead, they [HC] are carried over and burned in the next combustion
cycle, dramatically reducing emissions. In addition, air injection directed
into the combustion chamber increases the efficiency of the exhaust
reaction, significantly over Mazda's existing system during engine startup.
Together with the double-skin exhaust manifold, the new layout makes the
exhaust much hotter when it reaches the catalytic converter, speeding the
converter reaction for clean emissions from the moment the engine is
started.
Paul wrote:
Me: This is the first time I have heard of direct air injection into the
combustion
chamber. Not easy to do. It takes a lot of compressed air to make a
difference.
that takes horsepower.
Can't be positive about this but I think the combustion chamber they are
talking about is the thermal reactor combustion chamber which is that huge
cast iron exhaust manifold on the Gen II rotaries. I think they are
injecting air in the Renesis version.
Tracy Crook
tcrook@rotaryaviation.com
www.rotaryaviation.com
I think you might be right. Probably got garbled in the translation.
Paul Lamar
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