Mark,
Nice looking exhaust. I’m cheering
for your design to succeed. Did you attempt to measure the area of the
perforations in the inner tube, or did you just TLAR it?
Bryan
From: Rotary motors in
aircraft [mailto:flyrotary@lancaironline.net] On
Behalf Of Mark Steitle
Sent: Monday, April 12, 2010 12:02
PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re:
Tangential muffler
Copy you on that! What material type and thickness was the
Mistral muffler? Anyone know what their design was like?
I know that something fatigued and plugged the flow, but I never saw
a drawing of their muffler or had anyone explain how the failure actually
occurred. It could have been a baffle plate that was not well supported
on all sides. I don't see how that could happen to my muffler as the tube
is welded to both end plates and the exhaust gasses don't strike the tube
directly but swirl around it. Yes, a piece may fatigue over
time and crack off, but I can't imagine how it could plug up the
exhaust path. But I guess anything is possible if Murphy has his
way. I'll keep a close eye on it though. With a little finessing,
I'm pretty sure I can get my little inspection camera up the tailpipe. If
that fails, I can remove one of the O2 sensors and stick the camera through the
hole for a peek inside.
On Mon, Apr 12, 2010 at 8:30 AM, Ernest Christley <echristley@nc.rr.com> wrote:
Mark Steitle wrote:
Ernest,
Yes, I can inspect it by looking up the tailpipe with a borescope.
I can also look in through the three inlets. Initially I tried
drilling holes but soon realized that this was futile. That's when I
turned to the side grinder. Material is .065 inconel and is supported on
both ends. If it starts coming apart I can cut the ends off and try
something else. Mark
If you need a borescope to inspect it, there's no way you're going to
get a tool in there to round out the sides. Keep a close eye on those slot
corners. The worst case would be a chunk coming loose just enough to bend
over and clog the exhaust. Mistral's test pilot is reported to say,
"That sucks."