Paul,
           Can anyone tell me the temp that the exhaust will reach on a
rotary at full noise, or what temp the muffler will have to handle?  Neil.


About as high as 1800 F at full chat.
Furthermore the pulse frequency is as high as 14,000 pulses per minute or
233 pulses per second. This is very destructive exhaust system and mufflers.
Lots of energy in the exhaust. It is why the rotary makes a good turbo compound engine.

The solution is make them out of .065" 321 SS.
If money is no object make them out of .049" Inconel.
The best thing is to put nothing inside. Inside parts have been known
to melt and block the exhaust causing a crash. If there is nothing inside that can not happen. Most of the external parts will be cooled by air convection and or radiation. It is possible to put a cooling tube in the center of a tangential muffler and pass cooling air through it. Make it at least .065 thick if 321 SS.

Square or rectangular pipes are better than round.

Here are some configuration that do not use internal parts.


Paul Lamar