Hi Guys;
Here is an old spreadsheet I did a looooong time ago.  I just cleaned it
up a bit.

I did this (quickly) by stealing a torque curve from the 1981 Kenichi
Yamamoto
Rotary Engine book, pg41, figure 4.11 and trying to match the torque
curve in a spreadsheet.
The curve fitting was done manually and is rough...needs to be smoothed.

There are a lot of assumptions even assuming the basic torque curve is
correct.
The ratio of max/min torque is a bit high ->35.5/-7.5 (kg*m) compared to
say an
inputTemp(300K)/ExhaustTemp(1200K).
Figure 4.11 has a torque fluctuation for a rotor face that appears to be
720 degrees -
I stretched it out to 1080 degrees as would be expected for a wankel.
The values should probably be interpolated for each degree - I did it in
a spreadsheet
this way because it was a fast, first pass guess.
I multiplied the torque by 15% to simulate a Pport - the "mean" torque
looks reasonable
compared to a 200ft*lb output.

This does not (appear) to include any moment of inertia effects for the
rotating assembly,
I will see if I model them and solve this programatically.  It "may" be
possible to draw
some conclusions on the required flywheel moment of inertia, smoothness
and idle rpm.
Cheers
Cary


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