X-Virus-Scanned: clean according to Sophos on Logan.com
Return-Path: <msteitle@gmail.com>
Received: from mail-fx0-f216.google.com ([209.85.220.216] verified)
  by logan.com (CommuniGate Pro SMTP 5.3c2)
  with ESMTP id 3980883 for flyrotary@lancaironline.net; Wed, 18 Nov 2009 10:32:34 -0500
Received-SPF: pass
 receiver=logan.com; client-ip=209.85.220.216; envelope-from=msteitle@gmail.com
Received: by fxm8 with SMTP id 8so1342060fxm.27
        for <flyrotary@lancaironline.net>; Wed, 18 Nov 2009 07:31:57 -0800 (PST)
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:message-id:subject:from:to:content-type;
        bh=Shypf6C0TirdQgx0YbaM/jMKV/6+tp1x/mU9/JkV4Ic=;
        b=HB2PutdVV2SNLysRnfaU18w2V7Y4jl27ytiPO7rnt8KEcaVWKLTMI+h82l5sONZhH0
         Jck6EpK5mH0O9RlLYwmpOpuoYrHxD8atMphAb3TFSMbvMNSWenATfZybqm+rL47D69ht
         DAo8TSlNueUUqKevTjL37yViOYypNXn0T6tZM=
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=pocFC3qfd7m4bzFitKmk5JdKZKgjun/mTGGbQBmmCgbOgnx/4Xhh2hag05lHNcJGOa
         tuydcQ+zJJZ/jKsMMqwYfeqjlZO4fW+ixs1ODG6Q201GDi0LzJdl2c0tAWVQFtZPbyNY
         D1BvNhfjBvene4UzF6KUBVG5Nsm4tjG55AMug=
MIME-Version: 1.0
Received: by 10.204.36.197 with SMTP id u5mr3828646bkd.81.1258558317702; Wed, 
	18 Nov 2009 07:31:57 -0800 (PST)
In-Reply-To: <list-3980873@logan.com>
References: <list-3980873@logan.com>
Date: Wed, 18 Nov 2009 09:31:57 -0600
Message-ID: <5cf132c0911180731n6acdc9bfga65a01d6883a5948@mail.gmail.com>
Subject: Re: [FlyRotary] Fish tail muffler
From: Mark Steitle <msteitle@gmail.com>
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Content-Type: multipart/alternative; boundary=00032555771e74ae920478a6f1d3

--00032555771e74ae920478a6f1d3
Content-Type: text/plain; charset=ISO-8859-1

Lynn,

OK, now I see.  The 3/4" square tubing pieces go in the long wide exit of
the fishtail to stiffen it.  Makes sense now.

Thanks,
Mark

On Wed, Nov 18, 2009 at 9:16 AM, Lynn Hanover <lehanover@gmail.com> wrote:

> Lynn,
>
> I'm having a hard time visualizing the stack of 3/4" square tubing exhaust
> as you described.  Do you have any pictures?
>
> Mark
>
> Here you go...........
>
> Fish tails like those found on motorcycles are found at the end of
> absorption style mufflers that remove some of the high pressure pulses. The
> flat side (of any pressure vessle) will fatigue fail very quickly when
> exposed to pulses. The round muffler (pressure vessle) is ideal from the
> strength to weight and fatigue failure stand point.
>
> Like a large piston in a hydraulic system, a small amount of pressure
> produces a huge mechanical advantage over the piston or a flat or nearly
> flat section of a muffler, or the flat sides of a fish tail.
>
> So if it's flat it dies. Or even nearly flat. The further from round the
> shorter the life. You can extend life span in a flat section by bracing it
> so it cannot move. Movement (bending) is required for a fatigue failure, so
> no movement generally yields no failure.
>
>
> In the case of the CART piece it is after the turbocharger, so most of the
> pulses are already removed, and the square tubes provide extensive cross
> bracing to prevent movement. In any case the whole exhaust system is
> discarded after three heat cycles including the waste gate exhaust piece.
> Just to avoid a failure during a race. One reason why there is no more CART
> series.
>
> Lynn E. Hanover
>
> --
> Homepage:  http://www.flyrotary.com/
> Archive and UnSub:
> http://mail.lancaironline.net:81/lists/flyrotary/List.html
>
>

--00032555771e74ae920478a6f1d3
Content-Type: text/html; charset=ISO-8859-1
Content-Transfer-Encoding: quoted-printable

<div>Lynn, </div>
<div>=A0</div>
<div>OK, now I see.=A0 The 3/4&quot; square tubing pieces go in the long wi=
de exit of the fishtail to stiffen it.=A0 Makes sense now.</div>
<div>=A0</div>
<div>Thanks,<br>Mark<br><br></div>
<div class=3D"gmail_quote">On Wed, Nov 18, 2009 at 9:16 AM, Lynn Hanover <s=
pan dir=3D"ltr">&lt;<a href=3D"mailto:lehanover@gmail.com">lehanover@gmail.=
com</a>&gt;</span> wrote:<br>
<blockquote class=3D"gmail_quote" style=3D"PADDING-LEFT: 1ex; MARGIN: 0px 0=
px 0px 0.8ex; BORDER-LEFT: #ccc 1px solid">
<div>Lynn,</div>
<div>=A0</div>
<div>I&#39;m having a hard time visualizing the stack of 3/4&quot; square t=
ubing exhaust as you described.=A0 Do you have any pictures?=A0 </div>
<div>=A0</div>
<div>Mark<br></div>
<div>=A0</div>
<div>Here you go...........</div>
<div>=A0</div>
<div>Fish tails like those found on motorcycles are found at the end of abs=
orption style mufflers that remove some of the high pressure pulses. The fl=
at side (of any pressure vessle) will fatigue fail very quickly when expose=
d to pulses. The round muffler (pressure vessle) is ideal from the strength=
 to weight and fatigue failure stand point.</div>

<div>=A0</div>
<div>Like a large piston in a hydraulic system, a small amount of pressure =
produces a huge mechanical advantage over the piston or a flat or nearly fl=
at section of a muffler, or the flat sides of a fish tail. </div>
<div>=A0</div>
<div>So if it&#39;s flat it dies. Or even nearly flat. The further from rou=
nd the shorter the life. You can extend life span in a flat section by brac=
ing it so it cannot move. Movement (bending) is required for a fatigue fail=
ure, so no movement generally yields no failure. </div>

<div>=A0</div>
<div>=A0</div>
<div>In the case of the CART piece it is after the turbocharger, so most of=
 the pulses are already removed, and the square tubes provide extensive cro=
ss bracing to prevent movement. In any case the whole exhaust system is dis=
carded after three heat cycles including the waste gate exhaust piece. Just=
 to avoid a failure during a race. One reason why there is no more CART ser=
ies.</div>

<div>=A0</div>
<div>Lynn E. Hanover</div><br>--<br>Homepage: =A0<a href=3D"http://www.flyr=
otary.com/" target=3D"_blank">http://www.flyrotary.com/</a><br>Archive and =
UnSub: =A0 <a href=3D"http://mail.lancaironline.net:81/lists/flyrotary/List=
.html" target=3D"_blank">http://mail.lancaironline.net:81/lists/flyrotary/L=
ist.html</a><br>
<br></blockquote></div><br>

--00032555771e74ae920478a6f1d3--