X-Junk-Score: 0 [] X-Cloudmark-Score: 0 [] X-Cloudmark-Analysis: v=2.3 cv=H+OlPNQi c=1 sm=1 tr=0 a=zZ/DyiEhLoMDSERZ33v5aA==:117 a=jpOVt7BSZ2e4Z31A5e1TngXxSK0=:19 a=MeAgGD-zjQ4A:10 a=aOWVIxkx-zkA:10 a=pGLkceISAAAA:8 a=Ia-xEzejAAAA:8 a=xPyZ54XvAAAA:8 a=eRLigfuSAAAA:8 a=7g1VtSJxAAAA:8 a=0kaiJflvgjYH2DIzol8A:9 a=sHNCsA6OCx6e3yh7:21 a=mPV3MGIt5PD4R0UP:21 a=QEXdDO2ut3YA:10 a=Qa1je4BO31QA:10 a=gvSQh4r-fQ0A:10 a=S0wkRrzPavQA:10 a=aqmiGlZAkYxFYcTL4JAA:9 a=z2Xf5663sRRc2gjm:21 a=_M-u53Z33ilO-KDk:21 a=cgswvlhwo-nfTmV1:21 a=Urk15JJjZg1Xo0ryW_k8:22 a=LQCduUwlY3eUW_MavTj7:22 a=BfhXYjFvZD4iae-mNffo:22 a=grOzbf7U_OpcSX4AJOnl:22 From: "Andrew Martin andrew@martinag.com.au" Received: from mail-wr1-f48.google.com ([209.85.221.48] verified) by logan.com (CommuniGate Pro SMTP 6.2.14) with ESMTPS id 13195440 for flyrotary@lancaironline.net; Tue, 19 Nov 2019 21:08:47 -0500 Received-SPF: none receiver=logan.com; client-ip=209.85.221.48; envelope-from=andrew@martinag.com.au Received: by mail-wr1-f48.google.com with SMTP id w9so26241461wrr.0 for ; Tue, 19 Nov 2019 18:08:48 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=martinag-com-au.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to; bh=nihfOiM1kuHtoxuw1Ckgw/0yA1V3oaVovUKeh6ghD1c=; b=UShfGI6cUsh50bmH0Cj3Zjg8MaE83FcEHEUbT6+t/FD+aDzkQrmCJKBmpy0kTH1QNt U7Q7YxxsXxQ6DjMKsGCC8FFGXmsopLbG/EQM+8ReYs2g5omVRy7p9/m4uQ9+7XdHm2/d /Onf3ccbqhsFwma8VZx1/vfdhzVhnrEtMychJN7VWwm49tcXtKfTFmRlhL/unUiIGshM sGud3s3g45IvZDDeRRdidInJPi0VjjTOZsBSk/s8AbmDxpaJUTku5ZsTdHE5dvAnu03T TQileZ3d1A2Sg87fsBraaNrLzSf1i2kOLyCxh01LRRm9fkGXS9yDuCaK825yFOFOsPRn ivng== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to; bh=nihfOiM1kuHtoxuw1Ckgw/0yA1V3oaVovUKeh6ghD1c=; b=D1eg3/DPOCaSeAVKtD3+eidKO24ZXPMehZ4FtnreueVk3cje+y+A/1CFAuTCmwD4Xg hE6wxqNZlaJb0KmdgKDmvUGRuWzJZ4kVSuaRcWzRp7YClfal752jrz+oo75SiSuc7PDu zB05y3UmUsNwfKXorbBVceskJvtr7mYe/yWili6dc37vjxpHwj2D4AJvpeXum4IWZ0NY /1syAGVXPKy6xkfFjWM7Rs1U8W1+5t2J5RyE70YwSZLt/gBAYcC2SN6/4Kd6mllqYGTj VqICqwRqN+xrWmhQGrXsgThXbA/tiFuC90CGgRf4ZO0EY72dVctrToHJjmJKxJJbSGIv anUQ== X-Gm-Message-State: APjAAAU95j1oIbdQbcPuqv5etJi5OCE6vPtK2VtWSRYenYdUol/TQ1cV H+oGO7qfkY7xboDVX68IT6avKyty2Q5tF0nfjymuA6fYug== X-Google-Smtp-Source: APXvYqzDH9fQnIdvLPwXFJvPCPWCkl9QwwDsu7baCR96Kd/OwHBMUZxkj5NRxWSRnop3xDsX+E5lvgjv9jp6hX+AWrw= X-Received: by 2002:adf:f203:: with SMTP id p3mr193204wro.2.1574215710179; Tue, 19 Nov 2019 18:08:30 -0800 (PST) MIME-Version: 1.0 References: In-Reply-To: Date: Wed, 20 Nov 2019 10:07:52 +0800 Message-ID: Subject: Re: [FlyRotary] Re: Mufflers To: Rotary motors in aircraft Content-Type: multipart/alternative; boundary="000000000000349d760597bda896" --000000000000349d760597bda896 Content-Type: text/plain; charset="UTF-8" Matt, Mine is not like Gary's final design, he was striving for a silent exhaust, where he combined different ideas. whereas I'm ok with just not too loud, and I think the original Schwarzpipe design is good and easy to make. Just seems hard for people to visualize how it works. Finn. Yours looks like it would be very easy to experiment with, just add more holes and an outer pipe to your perforated section of pipe, both rear ends blocked off, with outlet only at front end. I reckon you could then do away with your muffler and save some weight. Andrew On Wed, Nov 20, 2019 at 1:30 AM Matt Boiteau mattboiteau@gmail.com < flyrotary@lancaironline.net> wrote: > Disregard the previous email. I was still reading the whole thread. From > Gary's thread, I attached the only picture that shows the Rotary. > > > https://www.homebuiltairplanes.com/forums/threads/quiet-flight.6560/page-3#post-69866 > > Above link breaks down the install Gary did on a rototiller. Basically > the header pipes enter a larger pipe (4inch in our case) from the side, > close to the top or bottom (not pointed to the middle) so exhaust swirls > around. Inside in the middle, is a perforated smaller pipe (2.5inch) that > exits out one end. You want the holes to double the volume of exit pipe. > The start of the perforated pipe is capped off, so the gasses are forced to > enter through the small holes. The end pipe is up to your design. I'll > probably go back to the coax style, or maybe swiss if I need to quite it > down even more. > > The 3d picture is one from Paul's newsletter. I think they had an air > opening at the front to try to decrease temperatures. Not sure, but > basically similar. Andrew, you said you had the inlet and outlet on the > same end, how does that look ? > > My first problem was I didn't cap off both ends of the perforated pipe. I > like the muffler idea using the stock manifold. Sadly I won't be back for > 2 months to the plane to weld new exhaust. Now to go find some 321 SS > piping in the meanwhile. > > - Matt Boiteau > > On 2019-11-19 10:37:04 AM, Matt Boiteau mattboiteau@gmail.com < > flyrotary@lancaironline.net> wrote: > Here is the picture from Andrew's email. > > My exhaust is stupid loud. I've tried a few things which didn't work. > Getting noise complaints around the airport while testing. > > Just reading this Gary Schwarz's link, looks promising. Andrew, did you > fit yours inside the cowl? I'm surprised 5mm endplates are holding up. > > - Matt Boiteau > > On 2019-11-19 12:57:36 AM, Andrew Martin andrew@martinag.com.au < > flyrotary@lancaironline.net> wrote: > > Kelly, I would if I had some, really did not expect it to work as I > deviated from the design a bit. Will be back at airport on weekend to take > photo, too late for construction photo. But nothing to it. > > I read about the idea by Gary Schwarz in this thread > , > post #7 , post #58 for his testing and post #142 sums up his findings. > Someone on here may know him as he was doing it for a rotary. Mine is much > shorter than his drawing below due to space constraints but the theory > works. > edit: Ahh!!! deleted his picture as too big to post. it is in his post #7 > mentioned above though. > Andrew > > -- > Homepage: http://www.flyrotary.com/ > Archive and UnSub: > http://mail.lancaironline.net:81/lists/flyrotary/List.html > --000000000000349d760597bda896 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Matt, Mine is not like Gary's final design, he wa= s striving for a silent exhaust, where he combined different ideas. whereas= I'm ok with just not too loud, and I think the original Schwarzpipe de= sign is good and easy to make. Just seems hard for people to visualize how = it works.
Finn. Yours looks like it would be very easy to exp= eriment with, just add more holes and an outer pipe to your perforated sect= ion of pipe, both rear ends blocked off, with outlet only at front end. I r= eckon you could then do away with your muffler and save some weight.
Andrew





<= div class=3D"gmail_quote">
On Wed, Nov= 20, 2019 at 1:30 AM Matt Boiteau = mattboiteau@gmail.com <flyrotary@lancaironline.net> wrote:
= Disregard the previous email. I was still reading the whole thread. From Ga= ry's thread, I attached the only picture that shows the Rotary.
https://www.homeb= uiltairplanes.com/forums/threads/quiet-flight.6560/page-3#post-69866

Above link breaks down the install Gary did on a=C2= =A0rototiller. Basically the= header pipes enter a larger pipe (4inch in our case) from the side, close = to the top or bottom (not pointed to the middle) so exhaust swirls around. = Inside in the middle, is a perforated smaller pipe (2.5inch) that exits out= one end. You want the holes to double the volume of exit pipe. The start o= f the perforated pipe is capped off, so the gasses are forced to enter thro= ugh the small holes. The end pipe is up to your design. I'll probably g= o back to the coax style, or maybe=C2=A0swiss=C2=A0if I need to quite it down=C2=A0even more.

The 3d picture is one from Paul's newslet= ter. I think they had an air opening at the front to try to decrease temper= atures. Not sure, but basically similar. Andrew, you said you had the inlet= and outlet on the same end, how does that look ?

My first problem w= as I didn't cap off both ends of the perforated pipe. I like the muffle= r idea using the stock manifold. Sadly=C2=A0I won't be back for 2 months to the plane to weld new e= xhaust. Now to go find some 321 SS piping in the meanwhile.

- Matt Boit= eau
=20

On 2019-11-19 10:37:04 AM, Matt Boiteau mattboiteau@gmail.com <flyrotary@lancaironline.net> wrote:

Here is the picture from Andrew'= ;s email.=C2=A0

My exhaust is stupid loud. I've trie= d a few things which didn't work. Getting noise complaints around the a= irport while testing.

Just reading this Gary Schwa= rz's link, looks promising. Andrew, did you fit yours inside the cowl? = I'm surprised 5mm endplates are holding up.

- = Matt Boiteau

On 2019-11-19 12:57:36 AM, Andrew Martin andrew@martinag.com.au <flyrotary@lancaironline.net= > wrote:


Kelly, I would if I had= some, really did not expect it to work as I deviated from the design a bit= . Will be back at airport on weekend to take photo, too late for constructi= on photo. But nothing to it.

I read = about the idea by Gary Schwarz in this thread, = post #7 , post #58 for his testing and post #142 sums up his findings.
<= /div>
Someone on here may know him as he was doing it for = a rotary. Mine is much shorter than his drawing below due to space constrai= nts but the theory works.
edit: Ahh!!! del= eted his picture as too big to post. it is in his post #7 mentioned above t= hough.
Andrew

-- Homepage:=C2=A0 http://www.flyrotary.com/
Archive and UnSub:=C2=A0 =C2=A0http://mail= .lancaironline.net:81/lists/flyrotary/List.html
--000000000000349d760597bda896--