Best done info and explanation I have seen so far.

http://www.eng.ed.ac.uk/~jchick/Y5/thesis/FormulaStudent/public_html/pt7.htm

Paul Lamar

Good discussion but what a lousy choice of engines to show the effect of
runner length on rpm (first chart on the link)
 The D type Jag is such an inherently low rpm design (drive one and see!)
that the effect of the runner length is mostly masked by basic engine
characteristics.  The shorter runners are trying in veign to pull the HP
curve upward.  If you tried to used this chart to choose a runner length for
your rotary, it would be a disaster.

In order to clearly see the effect of runner length on HP peak, the test
engine should be one capable of working well at the highest rpm of interest,
not an antique like the D Type Jag : )

Tracy

But of course. It is a piston engine. Poppet valves have their RPM limitations.
Particularly with a long stroke engine like the Jag six. Never the less it does
show trends and that is what I was after here. It also explains well the interaction
of long pipes and a large plenum chamber. It is the principle and not the
application to any particular type of engine we are interested in here.
Intermittent combustion engines suck intermittently even the rotary.

Perhaps you will like this one better.

http://www.mecc.unipd.it/~cos/DINAMOTO/risuonatore/risuonatore.html

Paul Lamar
 
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