Jerry Hey wrote:

I have often heard that the rotary needs a free flowing

exhaust.  Does

that mean that it would run best with short stubby straight

pipes?

Is
the tuned exhaust more efficient than no exhaust?   Considering

the

simple tangential muffler, if the exhaust pipe from the muffler

has a

larger area than the combined area of the two pipes feeding it,

would

that be considered "free flowing."  Consider two 2 inch pipes

feeders

at 6.28 sq. in. and a single 3 inch outlet 7.069 sq. in.

Another

question:  when the exhaust gas enters the "can" of the

tangential

muffler it is going to expand, slow down and become more

turbulent.

Would the gas lose significant heat as a result?   Thanks,

Jerry

The P-port runs best with 32 inch long open pipes at 6000 RPM.
27 inches long at 7000 RPM. Better than no exhaust. I would say

yes

on the larger exhaust pipe coming out of the muffler.
The muffler works by losing heat. As the pulses come out they

zing

around inside the can losing heat to the skin.
Paul Lamar

The can skin is a  large surface area that can dissipate a lot of

heat.

I wonder if 304 x .065  SS could be used for the can? It is

available

in the right diameters.    SS types   321,  253MA, and inconel

will

have be rolled and welded. And they are so expensive.  Jerry

304 is fine as long as it is .049 or thicker. .035 won't cut it.

Paul Lamar

  My grandfather's 1897 steam car has an "Exhaust silencer and lamp
holder" on it. He patented it in 1902 but never produced them or sold the
patent. Basically it is a tangential muffler with a large open end that
has slots that exhaust into a cone shaped external baffle that bounces
the sound backwards and directs it against a second cone on the outside
of the muffler body, and disperses it outward in all directions. His
instincts were excellent when he designed it because it is a combo of
dispersal, heat absorbtion and resonator all in one, and and with little
flow resistance, done at a time when noone knew about sound cycles,
reverbration or heat soak. I think it has a place even for the wankel.
George (Up-over.)

 
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