Obviously, it is possible to scale up a Wankel engine for relatively high
output
at lower output shaft rpm (ie 3000 or less). However, the Wankel is
demonstrably
a challenge for cooling, and as you scale any engine up, the heat paths
become

larger, and air cooling less practical. Even with virtual "micro milling" of
cooling fins,
the WWII radials ran out of size, and went to "corn cob" cylinder counts. I
really feel also, that the power to weight ratio would adversly suffer. If
you

halve the rpm at the same Brake Mean Effective Pressure, you have to double
the displacement. I think the big air cooled "direct" drive Wankel while
perhaps a good hope - is a faint one. - Vance

It might be possible, and maybe someone has tried, to solve the temperature
gradient problem on the rotor housing with different lenght cooling fins;
short to none on the intake side, long and plentiful on the combustion side,
graduating the lengths as you go around to "tailor" your heat profile.

Chris
microcosman.com

 
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