X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from mail02.syd.optusnet.com.au ([211.29.132.183] verified) by logan.com (CommuniGate Pro SMTP 5.2.11) with ESMTPS id 3432752 for flyrotary@lancaironline.net; Sun, 18 Jan 2009 16:45:09 -0500 Received-SPF: pass receiver=logan.com; client-ip=211.29.132.183; envelope-from=lendich@optusnet.com.au Received: from george (d220-236-171-208.dsl.nsw.optusnet.com.au [220.236.171.208]) by mail02.syd.optusnet.com.au (8.13.1/8.13.1) with SMTP id n0ILiR67003905 for ; Mon, 19 Jan 2009 08:44:28 +1100 Message-ID: From: "George Lendich" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: another Muffler Date: Mon, 19 Jan 2009 07:44:30 +1000 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_002D_01C97A09.C37FD980" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.5512 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.5579 X-Antivirus: avast! (VPS 090117-0, 17/01/2009), Outbound message X-Antivirus-Status: Clean This is a multi-part message in MIME format. ------=_NextPart_000_002D_01C97A09.C37FD980 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Steve/ Mike, The material used is not terribly thick, but it goes to show what will = stand up, with the muffler in the air stream and sufficient distance = from the exhaust ports. George (down under) ----- Original Message -----=20 From: Steven Boese=20 To: Rotary motors in aircraft=20 Sent: Monday, January 19, 2009 7:01 AM Subject: [FlyRotary] Re: another Muffler Mike, =20 The length of the cylindrical section is 24 inches. The conical = section is 9 inches long. =20 The dome was made from a Kmart mixing bowl. Some of it is less than = 0.032 inches thick but has held up so far. The cylindrical section was made by a local sheet metal shop with a = stove pipe joint that also has been tack welded in a few places. I made the conical section, inside parts, heat shield, and mount from = the same sheet material as the cylindrical section. The joint in the = conical section is similar to the stove pipe joint and is also tack = welded. =20 Steve Boese N613BX, RV6A, 1986 13B NA, EC2, RD1A =20 From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] = On Behalf Of Mike Wills Sent: Saturday, January 17, 2009 9:13 AM To: Rotary motors in aircraft Subject: [FlyRotary] Re: another Muffler =20 Quite the opposite Steve. I think the 3 Kt loss and looks (it actually = looks better than most) is a fair price to payfor a relatively light, = easy to construct muffler that works. My current "muffler" isnt a lot = smaller and weighs about the same. =20 Questions: =20 1) Overall length? 2) Source for the dome and cone used in the construction? =20 Thanks, =20 Mike Wills N144MW ----- Original Message -----=20 From: sboese=20 To: Rotary motors in aircraft=20 Sent: Friday, January 16, 2009 9:57 AM Subject: [FlyRotary] another Muffler =20 =20 The following muffler description is provided purely as another data = point in the muffler discussion. I would suspect that not many of you = would be interested in it due to its large size and external mounting. = I have had good service from it so far and it fits somewhat into my = loosely interpreted Navy F6F Hellcat inverted paint scheme as a bomb. =20 The materials of construction are 0.032" thick 304 SS and the design = is based on data in NACA Report 1192. The weight is 9.6 lb and the = diameter is 6.25 inches. A SS heat shield is also installed between the = muffler and the fuselage belly. I have about 100 hours on this = installation with no signs of deterioration of the muffler. The engine = is NA with exhaust splitters and is operated normally at density = altitudes above 7000 ft which limits max power, although several hours = of max power operation at DA lower than 5000 ft have not damaged this = muffler so far. =20 I have been told that from the ground, the primary source of noise = for my plane is the propeller. I have landed with a C172 following me = in the pattern and observers told me that they did not know I was there = until I taxied in since they only heard the C172. I have no = quantitative data on the noise characteristics of my muffler system. = Inside the cockpit, the noise level goes from reasonable to unbearable = if the muffler is removed. This is purely subjective, of course. =20 =20 Not shown in the "muffler parts" image are three 1" x 1" angles made = from the same material as the shell that connect the rear of the = internal center tube to the front of the rear cone section. The round = flange in the center of the internal tube is a push fit in the shell and = is not fastened directly to the shell. A down turn also has been added = to the outlet of the rear cone section. =20 From data in the "muffler test chart" image, the speed penalty of = the muffler is about 3 kt. =20 The "muffler in flight" photo may be of interest in that it shows = the heat distribution in the muffler with the dark areas being hotter. = This image is not current since the lower cowling has been modified and = the engine cooling air outlet is now much smaller than shown in this = photo. =20 Steve Boese RV6A, 1986 13B NA, EC2, RD1A=20 -------------------------------------------------------------------------= --- -- Homepage: http://www.flyrotary.com/ Archive and UnSub: = http://mail.lancaironline.net:81/lists/flyrotary/List.html -------------------------------------------------------------------------= ----- -- Homepage: http://www.flyrotary.com/ Archive and UnSub: = http://mail.lancaironline.net:81/lists/flyrotary/List.html ------=_NextPart_000_002D_01C97A09.C37FD980 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Steve/ Mike,
The material used is not terribly = thick, but it=20 goes to show what will stand up, with the muffler in the air stream and=20 sufficient distance from the exhaust ports.
George (down under)
----- Original Message -----
From:=20 Steven = Boese
Sent: Monday, January 19, 2009 = 7:01=20 AM
Subject: [FlyRotary] Re: = another=20 Muffler

Mike,

 

The=20 length of the cylindrical section is 24 inches.  The conical = section is 9=20 inches long. 

The=20 dome was made from a Kmart mixing bowl.  Some of it  is less = than=20 0.032 inches thick but has held up so far.

The=20 cylindrical section was made by a local sheet metal shop with a stove = pipe=20 joint that also has been tack welded in a few = places.

I=20 made the conical section, inside parts, heat shield, and mount from = the same=20 sheet material as the cylindrical section.  The joint in the = conical=20 section is similar to the stove pipe joint and is also tack=20 welded.

 

Steve=20 Boese

 N613BX,=20 RV6A,  1986 13B NA, EC2, RD1A

 

From: Rotary = motors in=20 aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Mike = Wills
Sent: Saturday, January 17, 2009 9:13 AM
To: = Rotary=20 motors in aircraft
Subject: [FlyRotary] Re: another=20 Muffler

 

Quite the = opposite=20 Steve. I think the 3 Kt loss and looks (it actually looks better than = most) is=20 a fair price to payfor a relatively light, easy to construct = muffler that=20 works. My current "muffler" isnt a lot smaller and weighs about the=20 same.

 

Questions:

 

1) = Overall=20 length?

2) Source = for the=20 dome and cone used in the construction?

 

Thanks,

 

Mike=20 Wills

N144MW

----- = Original=20 Message -----

From: sboese=20

To: Rotary motors in = aircraft=20

Sent: = Friday, January=20 16, 2009 9:57 AM

Subject: = [FlyRotary]=20 another Muffler

 

 

The=20 following muffler description is provided purely as another data = point in=20 the muffler discussion.  I would suspect that not many of you = would be=20 interested in it due to its large size and external mounting.  = I have=20 had good service from it so far and it fits somewhat into my loosely = interpreted Navy F6F Hellcat inverted paint scheme as a=20 bomb.

 

The=20 materials of construction are 0.032=94 thick 304 SS and the design = is based on=20 data in NACA Report 1192.  The weight is 9.6 lb and the = diameter is=20 6.25 inches.  A SS heat shield is also installed between the = muffler=20 and the fuselage belly.  I have about 100 hours on this = installation=20 with no signs of deterioration of the muffler.  The engine is = NA with=20 exhaust splitters and is operated normally at density altitudes = above 7000=20 ft which limits max power, although several hours of max power = operation at=20 DA lower than 5000 ft have not damaged this muffler so=20 far.

 

I=20 have been told that from the ground, the primary source of noise for = my=20 plane is the propeller.  I have landed with a C172 following me = in the=20 pattern and observers told me that they did not know I was there = until I=20 taxied in since they only heard the C172.  I have no = quantitative data=20 on the noise characteristics of my muffler system.  Inside the = cockpit,=20 the noise level goes from reasonable to unbearable if the muffler is = removed.  This is purely subjective, of course. =20

 

Not=20 shown in the =93muffler parts=94 image are three 1=94 x 1=94 angles = made from the=20 same material as the shell that connect the rear of the internal = center tube=20 to the front of the rear cone section.  The round flange in the = center=20 of the internal tube is a push fit in the shell and is not fastened = directly=20 to the shell.  A down turn also has been added to the outlet of = the=20 rear cone section.

 

From=20 data in the =93muffler test chart=94 image, the speed penalty of the = muffler is=20 about 3 kt.

 

The=20 =93muffler in flight=94 photo may be of interest in that it shows = the heat=20 distribution in the muffler with the dark areas being hotter.  = This=20 image is not current since the lower cowling has been modified and = the=20 engine cooling air outlet is now much smaller than shown in this=20 photo.

 

Steve Boese

RV6A, 1986 13B NA, EC2, RD1A=20

--
Homepage: =20 http://www.flyrotary.com/
Archive and UnSub:  =20 = http://mail.lancaironline.net:81/lists/flyrotary/List.html

=

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Homepage:  http://www.flyrotary.com/
Archive and=20 UnSub:  =20 = http://mail.lancaironline.net:81/lists/flyrotary/List.html
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