X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from ms-smtp-02.southeast.rr.com ([24.25.9.101] verified) by logan.com (CommuniGate Pro SMTP 5.0.9) with ESMTP id 1090008 for flyrotary@lancaironline.net; Wed, 03 May 2006 08:14:28 -0400 Received-SPF: pass receiver=logan.com; client-ip=24.25.9.101; envelope-from=eanderson@carolina.rr.com Received: from edward2 (cpe-024-074-025-165.carolina.res.rr.com [24.74.25.165]) by ms-smtp-02.southeast.rr.com (8.13.6/8.13.6) with SMTP id k43CDgtR029582 for ; Wed, 3 May 2006 08:13:43 -0400 (EDT) Message-ID: <001401c66eab$0823e170$2402a8c0@edward2> From: "Ed Anderson" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: Muffler cones Date: Wed, 3 May 2006 08:13:47 -0400 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0011_01C66E89.80C84020" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.2869 X-MIMEOLE: Produced By Microsoft MimeOLE V6.00.2900.2869 X-Virus-Scanned: Symantec AntiVirus Scan Engine This is a multi-part message in MIME format. ------=_NextPart_000_0011_01C66E89.80C84020 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Hi Bill, I've tried about 4 experiment with mufflers - all basically trying to = soften the shock wave. I had a couple that really quieted the engine - = but at cost of back pressure and lost power. A couple that did a modest = job of taking the metallic content down - but those soon disintegrated = (the internals). But, then again, most of the baffles were = perpendicular to the shock wave and just couldn't take the pounding. A = cone or similar oblique surface would likely survive longer. I agree = the perforated tube is likely to not be able to take the pounding = especially with the cones attached. I said I was through trying muffler experiments, but have to admit I am = tempted to try one more time with cones {:>) Ed ----- Original Message -----=20 From: WRJJRS@aol.com=20 To: Rotary motors in aircraft=20 Sent: Wednesday, May 03, 2006 1:37 AM Subject: [FlyRotary] Re: Muffler cones In a message dated 5/2/2006 5:43:53 PM Pacific Standard Time, = eanderson@carolina.rr.com writes: George, here was my idea of a muffler using cones. The center = (smaller)=20 tube is perforated with the cone attached to it. Room at the widest = part of=20 the cone and wall of outer tube for gas to pass. A variation was to = have=20 the cone extend to the outer tube wall and have all cones facing the = header=20 end of the muffler only permitting gas (and sound) through the = perforated=20 center tube. Ed Ed, If I might jump in here. This looks like it should work. The muffling won't be tremendous but = it should really take the edge off. Bending the shock wave really takes = something stout with the rotary, doesn't it? I think the spiro-flow = might work and survive better though. (The one that looks like an auger = trapped in a can.) I always worry about perf tube with the rotary, when = it gets super hot it seems like the pulses try to tear it off like a = perf paper! You really know what you're up against after the washers = though so best of luck. Bil Jepson ------=_NextPart_000_0011_01C66E89.80C84020 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Hi Bill,
 
I've tried about 4 experiment with mufflers - all = basically=20 trying to soften the shock wave.  I had a couple that really = quieted the=20 engine - but at cost of back pressure and lost power.  A couple = that did a=20 modest job of taking the metallic content down - but those soon = disintegrated=20 (the internals).   But, then again, most of the baffles were=20 perpendicular to the shock wave and just couldn't take the = pounding.  A=20 cone or similar oblique surface would likely survive longer.  I = agree the=20 perforated tube is likely to not be able to take the pounding especially = with=20 the cones attached.
 
I said I was through trying muffler experiments, but = have to=20 admit I am tempted to try one more time with cones {:>)
 
Ed
----- Original Message -----
From:=20 WRJJRS@aol.com
Sent: Wednesday, May 03, 2006 = 1:37=20 AM
Subject: [FlyRotary] Re: = Muffler=20 cones

In a message dated 5/2/2006 5:43:53 PM Pacific Standard Time, eanderson@carolina.rr.com=20 writes:
George, here was my  idea of a muffler using = cones.  The=20 center (smaller)
tube is perforated with the cone attached to = it. =20 Room at the widest part of
the cone and wall of outer tube for = gas to=20 pass.  A variation was to have
the cone extend to the outer = tube=20 wall and have all cones facing the header
end of the muffler = only=20 permitting gas (and sound) through the perforated
center=20 tube.

Ed
Ed, If I might jump in here.
 This looks like it should work. The muffling won't be = tremendous=20 but it should really take the edge off. Bending the shock wave really = takes=20 something stout with the rotary, doesn't it? I think the spiro-flow = might work=20 and survive better though. (The one that looks like an auger trapped = in a=20 can.)  I always worry about perf tube with the rotary, when it = gets super=20 hot it seems like the pulses try to tear it off like a perf paper! You = really=20 know what you're up against after the washers though so best of = luck.
Bil Jepson 
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