Jerry Hey wrote:

Here is how version  3 of my exhaust system turned out.   The muffler
to rad clearance is 4.375 inches.  Plenty of room for a shield.

    Another feature are the bellows.  With them I  can wiggle the
muffler an inch any direction. Of course it will eventually be secured
to the aircraft frame. I am just going to tack weld the bellows. In the
event they burn out, they can be removed with  a little grinding.  I
thought about kerfing the collars and clamping the bellows in place.
Probably should have done that.

  Another feature is the tube within a tube concept at the  flange. This
was done by welding a stub to the inside of the flange.  This sticks
about about an inch.  The outer pipe which is expanded to fit loosely
over the stub is welded to the outside of the flange.   BTW I like the
heavy stock exhaust flange as opposed to the light weight Hatch type
flange.  The heavy flanges can absorb a lot of heat without getting
that hot. They should help control the temps in the first inch of
exhaust pipe where PowerSport's burned off.

This is intended to be a free flowing system. As far as noise is
concerned  I am hoping that the exhaust pulse will become disorganized
when  it dumps into the pre-muffler and then tumbles out the square
muffler.   If it is too loud, I am prepared to add turbulators in the
downward sloping portion of the muffler.  The exhaust pipes are "tuned"
at 16 inches (32/2) in length. To get the length I had to extend the
pipes into the pre-muffler about an inch or so.

The entire system is made out of 304 SS.  The exhaust pipes are .065
and the muffler is .070.  The curved face on the  pre-muffler was made
heat and a hammer.    Jerry

Jerry,

  Where did you get the exhaust bellows? I take it that it is also 304 SS?
Any guesses as to how well it will stand up to the heat? Might be a
solution for me but I'd need it in 2.5" size to go in after the collector
on my header.

Mike Wills

 
The AirCraft Rotary Engine NewsLetter.  Powered by Linux.
ACRE NL web site. http://home.earthlink.net/~rotaryeng/            
Copyright 1998-2002 All world wide rights reserved.