X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from mail-pw0-f52.google.com ([209.85.160.52] verified) by logan.com (CommuniGate Pro SMTP 5.3.5) with ESMTP id 4218896 for flyrotary@lancaironline.net; Mon, 12 Apr 2010 14:44:15 -0400 Received-SPF: pass receiver=logan.com; client-ip=209.85.160.52; envelope-from=msteitle@gmail.com Received: by pwi1 with SMTP id 1so4756627pwi.25 for ; Mon, 12 Apr 2010 11:43:39 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:in-reply-to:references :date:received:message-id:subject:from:to:content-type; bh=+s7j0RrNjdyh3X+Z5YTukT+eOPz0QXBviMcylvtmxvE=; b=TDcfZLwXQ7FtJ19FwpHMmaqPl4i8xxeodTbfd0JUY3v6bdxvnZH93b4LSkFW4B/A1j HtDU2RreEhGI8/flQhNlvH0S5ki9Kmvt7auPoEvsXD1+9wRzvPGPWinTfyr7T2wRsBAu 8ADAVMjnrNm53XGVv9+RF/x9P2nD7zWA93JJA= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; b=n3RwgvnK45PsyPLZBETudhY5kLvWGQlykIsxL0ehkaiHLhccSfP8ZP1ZWvmoiEHksi XF/fnDnaeUCMrZ78oVMPp76wk6KT9T2A2L0xXhUxYiaTbjCYY48W+ur2N5igI7fUpvfX q9fBxz4RXcBF4HOYsB2R1FZeodLb7WDhKjlOY= MIME-Version: 1.0 Received: by 10.231.183.195 with HTTP; Mon, 12 Apr 2010 11:43:38 -0700 (PDT) In-Reply-To: References: Date: Mon, 12 Apr 2010 13:43:38 -0500 Received: by 10.141.12.12 with SMTP id p12mr4089641rvi.130.1271097818857; Mon, 12 Apr 2010 11:43:38 -0700 (PDT) Message-ID: Subject: Re: [FlyRotary] Re: Tangential muffler From: Mark Steitle To: Rotary motors in aircraft Content-Type: multipart/alternative; boundary=000e0cd10632f7c29504840e85f5 --000e0cd10632f7c29504840e85f5 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: quoted-printable Dwane, OK, you hold your hand over the end while I rev it up. ;-0 Keep in mind that in an earlier muffler design similar to the Moroso Spiralflow, I had an AN-3 bolt holding the baffle in place. After a few hours the bolt had gotten so hot that it sagged, resembling a horseshoe. The rotary's exhaust has proven to be a force to be reconed with. Hopefully, this will be the last muffler I have to build for a while. Mark On Mon, Apr 12, 2010 at 1:19 PM, Dwayne Parkinson wrote: > This is a very interesting approach. Thanks for posting the pictures. > It would be very interesting (at least to me) to measure the exhaust gas > pulses at the tail pipe with this design. I wonder if it will normalize = the > pulses at all so you have an almost steady stream of exhaust gases coming > out of the pipe. > > > > ------------------------------ > *From:* Al Gietzen > *To:* Rotary motors in aircraft > *Sent:* Mon, April 12, 2010 10:24:07 AM > *Subject:* [FlyRotary] Re: Tangential muffler > > > > > > Ernest; > > > > I agree that the geometry of the geometry of the cuts is certainly not > ideal; and if it were 321SS or similar; yes, I=92d expect it would it to > disintegrate in about 50 hrs or less. But inconel is very corrosion > resistant and very strong up to 2000+F. There will be some self-annealin= g > of the stresses at 1700F. It would be interesting to know what temp it > actually gets to because there is some expansion cooling of the gases in = the > muffler. > > > > Also it is very tough stuff =96 trying to drill or file inconel will just > wear out the tools. Holes have to be punched, cut with water jet, or som= e > other technique. > > > > It will be interesting to see how it stands up; but I think it has a good > chance to prove to be quite durable. > > > > Al > > > > A grinder will leave two fairly severe 90 degree corners on every edge > > of the cut slot. Compounding this is the fact that the side grinder > > cuts a circle. The end of each slot will be left with a knife edge > > profile pointing back toward the slot. This will create some mean > > stress risers. The expectation is that this tube is to live in an > > environment that has to be the closest thing to hell on Earth we could > > imagine (extreme heat and constant sonic blasts). > > > > I would have suggested drilling 3/16" holes and connecting them with the > > grinder. Unless the inside tube is fabricated different than what I > > understand, I can't help but to think that it will have a very short > > life. Cracks will start in the corners of each slot, and the tube will > > disintegrate. Can it be easily pulled apart so that you could run a > > round needle file down both sides of all the slots to round them out? > > > > -- > > Homepage: http://www.flyrotary.com/ > > Archive and UnSub: > http://mail.lancaironline.net:81/lists/flyrotary/List.html > > --000e0cd10632f7c29504840e85f5 Content-Type: text/html; charset=windows-1252 Content-Transfer-Encoding: quoted-printable
Dwane,
=A0
OK, you hold your hand over the end while I rev it up.=A0 ;-0=A0
=A0
Keep in mind that in an earlier muffler design similar to the Moroso S= piralflow, I had an AN-3 bolt holding the baffle in place.=A0 After a few h= ours the bolt had gotten so hot that it sagged, resembling a horseshoe.=A0 = The rotary's exhaust has proven to be a force to be reconed with.=A0 Ho= pefully, this will be the last muffler I have to build for a while.
=A0
Mark

On Mon, Apr 12, 2010 at 1:19 PM, Dwayne Parkinso= n <dwayne= parkinson@yahoo.com> wrote:
This is a very interesting approach. =A0Thanks for posting the picture= s. =A0It would be very interesting (at least to me) to measure the exhaust = gas pulses at the tail pipe with this design. =A0I wonder if it will normal= ize the pulses at all so you have an almost steady stream of exhaust gases = coming out of the pipe.


<= br>
From: Al Gietzen <ALVentures@cox.net>= ;
To: Rotary motors in a= ircraft <flyrotary@lancaironline.net>
Sent: Mon, April 12, 2010 1= 0:24:07 AM
Subject: [Fly= Rotary] Re: Tangential muffler

=A0

=A0

Ernest;=

=A0

I agree that the geometry of the geometry of the cuts is ce= rtainly not ideal; and if it were 321SS or similar; yes, I=92d expect it wo= uld it to disintegrate in about 50 hrs or less.=A0 But inconel is very corr= osion resistant and very strong up to 2000+F.=A0 There will be some self-an= nealing of the stresses at 1700F.=A0 It would be interesting to know what t= emp it actually gets to because there is some expansion cooling of the gase= s in the muffler.

=A0

Also it is very tough stuff =96 trying to drill or file inc= onel will just wear out the tools.=A0 Holes have to be punched, cut with wa= ter jet, or some other technique.

=A0

It will be interesting to see how it stands up; but I think= it has a good chance to prove to be quite durable.

=A0

Al

=A0

A grind= er will leave two fairly severe 90 degree corners on every edge

of the = cut slot.=A0 Compounding this is the fact that the side grinder

cuts a = circle.=A0 The end of each slot will be left with a knife edge

profile= pointing back toward the slot.=A0 This will create some mean

stress = risers.=A0 The expectation is that this tube is to live in an

environ= ment that has to be the closest thing to hell on Earth we could

imagine= (extreme heat and constant sonic blasts).

=A0

I would= have suggested drilling 3/16" holes and connecting them with the

grinder= .=A0 Unless the inside tube is fabricated different than what I

underst= and, I can't help but to think that it will have a very short

life.= =A0 Cracks will start in the corners of each slot, and the tube will

disinte= grate. Can it be easily pulled apart so that you could run a =

round n= eedle file down both sides of all the slots to round them out?

=A0

--

H= omepage:=A0 http://= www.flyrotary.com/

A= rchive and UnSub:=A0=A0 http://mail.lancaironline.net:81/list= s/flyrotary/List.html



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