X-Junk-Score: 0 [] X-Cloudmark-Score: 0 [] X-Cloudmark-Analysis: v=2.3 cv=F7spiZpN c=1 sm=1 tr=0 a=SICaYfXyTL5dc3ZhdRd39Q==:117 a=kloI1ui9B+OOwk393D4IlA==:17 a=jpOVt7BSZ2e4Z31A5e1TngXxSK0=:19 a=x7bEGLp0ZPQA:10 a=A-0mRrAPPO4A:10 a=MeAgGD-zjQ4A:10 a=r77TgQKjGQsHNAKrUKIA:9 a=pGLkceISAAAA:8 a=Ia-xEzejAAAA:8 a=hOpmn2quAAAA:8 a=eRLigfuSAAAA:8 a=xPyZ54XvAAAA:8 a=meJbv3C4AAAA:8 a=7g1VtSJxAAAA:8 a=FEd23BpTAAAA:8 a=CLLD_PPFk3j_3sSpo2IA:9 a=8RXZYcVjRLLNgp1-:21 a=jsFqCwpJj4nWQgYT:21 a=QEXdDO2ut3YA:10 a=Qa1je4BO31QA:10 a=N5n9HDkQ76oA:10 a=oOz5yF6qyDwA:10 a=gvSQh4r-fQ0A:10 a=4PR2P7QzAAAA:8 a=5_ppEN-z1FZX9zQNPbwA:9 a=0Czs05MjUkbG0CVV:21 a=wjq_mHCSHF8Q64zU:21 a=agTXcoAwHs9xMOFE:21 a=_W_S_7VecoQA:10 a=Urk15JJjZg1Xo0ryW_k8:22 a=GyA-uvUxXSCciAkwuKQO:22 a=BfhXYjFvZD4iae-mNffo:22 a=LQCduUwlY3eUW_MavTj7:22 a=grOzbf7U_OpcSX4AJOnl:22 a=80WO7EPaVbmEDwVs73Zs:22 a=4dqwQCo7Po2mVW515mGf:22 From: "Charlie England ceengland7@gmail.com" Received: from mail-yw1-f41.google.com ([209.85.161.41] verified) by logan.com (CommuniGate Pro SMTP 6.2.14) with ESMTPS id 13202965 for flyrotary@lancaironline.net; Thu, 21 Nov 2019 12:27:02 -0500 Received-SPF: pass receiver=logan.com; client-ip=209.85.161.41; envelope-from=ceengland7@gmail.com Received: by mail-yw1-f41.google.com with SMTP id d80so1489466ywa.6 for ; Thu, 21 Nov 2019 09:27:02 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:references:from:message-id:date:user-agent:mime-version :in-reply-to:content-language; bh=GJIPFGpntYc4esgs09ioVLfQb1qDxTYlhM1RGybcX7c=; b=mNJB9MHqiRvGfmxQoxi0wXaMUuy2AW249Jxl2q/cKDjjEhfSugxIIIhHnzf36CqyJb qyDacnAOCVHsEVJYA92emf1nqrDwXuSbx6hBHaa7W38GD5Oy+u3vAlYdqYyOE3FOVigp SZ0fW1nx9FNp8E6uLHaBWgMngbfz1IumUZ28XKn0uBbZzJteuO8BY9yiPn2ipu9wZPT9 3rOsNlHlQzHQWkfyeU4FPuXLRt7QOHNZdSa+S+oVD3IlKkbrA4ZjesE/uVHpgDK2Hrov Q0fy3R9DvWBJDxF5AE3fT+fjKQrLuZxTAI5XqA5X9aTJQfv9wcdO6uEOezgQ77kDMz0A JJzQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language; bh=GJIPFGpntYc4esgs09ioVLfQb1qDxTYlhM1RGybcX7c=; b=mnfxvOJ4xirhcXyY3lKCsGtR0BVGtzql7s6re6RZzAMmplDGSoNtQd6HoQMC2aVTUz z2hUUUw7FJGm0GSdxqeFHxkbKWXe5NvhCSl4D5MFZyQ3+iWqB9hDQBV5aiWJTKahyTug Kn7WyD2qRQ9EMC6QC9CxPPmObWqiMQSerlTMmba9mHPX3o91u+dH3fTFHQX7clN5rOUp n47NkYXrUYxM0OsnyAwSvGOSwqemwGzLlndFIr9tQDVUXOIC9azCJ9fKH2ncvrawjSPX iCN8TpVX0yAO5IF1Np1+FI6BKXUioTah1qiOwXu2Kn+rx0igrCQT9vSfO95aJ2J7aDHV OWQw== X-Gm-Message-State: APjAAAXluuNzSEY4iiXa9yfYfq18K7RbaDQpoTYkodFd8WxCIxvABIG9 ImDuLE0yTbb3bPoPsTfvTM5e/G0d X-Google-Smtp-Source: APXvYqz4qshPxqrXWSSEAPHiy/i9Rx5LknnzNyyrRyCRbwv1tLrGQBmAXiRtj8cVbdwbke3UY5voLA== X-Received: by 2002:a81:3341:: with SMTP id z62mr6156839ywz.242.1574357204715; Thu, 21 Nov 2019 09:26:44 -0800 (PST) Return-Path: Received: from [192.168.10.246] (mobile-166-173-250-183.mycingular.net. [166.173.250.183]) by smtp.googlemail.com with ESMTPSA id j144sm1041888ywg.77.2019.11.21.09.26.42 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 21 Nov 2019 09:26:44 -0800 (PST) Subject: Re: [FlyRotary] Re: Mufflers To: Rotary motors in aircraft References: Message-ID: Date: Thu, 21 Nov 2019 11:26:44 -0600 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.9.1 MIME-Version: 1.0 In-Reply-To: Content-Type: multipart/alternative; boundary="------------124B0733892ED240F7940285" Content-Language: en-US X-Antivirus: Avast (VPS 191119-0, 11/19/2019), Outbound message X-Antivirus-Status: Clean This is a multi-part message in MIME format. --------------124B0733892ED240F7940285 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit On 11/21/2019 11:03 AM, Kelly Troyer keltro@gmail.com wrote: > > > On Wed, Nov 20, 2019 at 12:45 PM Charlie England ceengland7@gmail.com > > wrote: > > On 11/20/2019 10:22 AM, David Leonard wdleonard@gmail.com > wrote: >> Marcus, >> I am really glad you brought up the Mistral incident, as I have >> been meaning to mention it too. For what it's worth, my >> experience with mufflers confirms what many other have said.  The >> exhaust environment in rotary aircraft is very extreme and >> component  failure can be catastrophic.  I have tried several >> types of high end packing, and nothing survives more than a few >> hours.  300 series stainless tolerates the heat, but any welds on >> thin stainless have limited life.  I would be very suspicious of >> anything with complex innards like the Aero Turbine 2525.  Doing >> what Jeff Whaley did by adding perforations should be a must-do >> in my opinion. >> >> Dave Leonard >> >> On Wed, Nov 20, 2019 at 5:59 AM Marcus Wiese cardmarc@charter.net >> > > wrote: >> >> Just remember the Mistral muffler event. The muffler caused >> the Piper Arrow  (?) with their rotary to crash after the >> internals blocked the outlet and led to power loss. It may >> have partially led to their withdrawal from the engine/PSRU >> market. To all our loss. >> M >> >> Sent from my iPad >> >>> On Nov 20, 2019, at 12:28 AM, Matt Boiteau >>> mattboiteau@gmail.com >>> >> > wrote: >>> >>>  >>> This is the Aero Exhaust 2525XL diagram. I have one, but >>> left it in Canada. Will bring it back with me in Jan to try >>> at taming the exhaust again. >>> >>> >>> >>> - Matt Boiteau >>>> >>>> On 2019-11-19 3:23:50 PM, Charlie England >>>> ceengland7@gmail.com >>>> >>> > wrote: >>>> >>>> >>>> >>>> On Mon, Nov 18, 2019 at 11:57 PM Andrew Martin >>>> andrew@martinag.com.au >>>> >>> > 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 >>>> >>>> That looks a lot like a simplified version (one less turn) >>>> of a standard automotive muffler. >>>> https://auto.howstuffworks.com/muffler3.htm >>>> The Aeroturbine tries to achieve similar effect (without >>>> the flow reversals) by using venturi effect to suck part of >>>> the exhaust around and then back into the central tube. >>>> >>>> Charlie >>>> >>> <2525.JPG> >>> -- >>> Homepage: http://www.flyrotary.com/ >>> Archive and UnSub: >>> http://mail.lancaironline.net:81/lists/flyrotary/List.html >> > The caution about potential blockage is warranted on any engine, > but obviously a greater danger with the rotary's powerful pulses. > > It's worth mentioning that the Renesis' exhaust should be > significantly less 'violent' than a 13B, for a couple of reasons. > The exhaust has to take a 'sharp right' as it exits the combustion > chamber, which helps break up the shock wave a bit, but even more > importantly, the exhaust port, instead of 'snapping open' like a > piston ported two stroke, opens more gradually, more like a > conventional poppet valve in a piston engine. > > As a FWIW on the Aeroturbine: I don't have a 2525XL to examine, > but the regular 2525 (minus the 1st chamber of the XL) is a > 'straight through' design. That cone on the input end is open. > Drawing of the guts is on the Aeroturbine web site. > https://aeroexhaust.com/i-30497606-aero-exhaust-turbine-at2525-performance-muffler-2-5-inside-diameter-necks-aggressive-sound.html > > IIRC, Tracy's been flying one on the 20B powered RV-8 for a number > of years. That's what motivated me to purchase one, but it hasn't > seen any exhaust gas yet. > > Charlie > > >   Charlie,, >       Any idea how many hours Tracy has on his AeroTurbine > 2525.............? > -- > Kelly Troyer > Dyke Delta_"Eventually" > 13B_RD1C_EC2_EM2 I don't, but I believe that it's been flying for a number of years with that muffler. Hopefully he'll see this thread & give us some 1st hand info. Charlie --------------124B0733892ED240F7940285 Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: 8bit
On 11/21/2019 11:03 AM, Kelly Troyer keltro@gmail.com wrote:


On Wed, Nov 20, 2019 at 12:45 PM Charlie England ceengland7@gmail.com <flyrotary@lancaironline.net> wrote:
On 11/20/2019 10:22 AM, David Leonard wdleonard@gmail.com wrote:
Marcus,
I am really glad you brought up the Mistral incident, as I have been meaning to mention it too.  For what it's worth, my experience with mufflers confirms what many other have said.  The exhaust environment in rotary aircraft is very extreme and component  failure can be catastrophic.  I have tried several types of high end packing, and nothing survives more than a few hours.  300 series stainless tolerates the heat, but any welds on thin stainless have limited life.  I would be very suspicious of anything with complex innards like the Aero Turbine 2525.  Doing what Jeff Whaley did by adding perforations should be a must-do in my opinion.

Dave Leonard

On Wed, Nov 20, 2019 at 5:59 AM Marcus Wiese cardmarc@charter.net <flyrotary@lancaironline.net> wrote:
Just remember the Mistral muffler event. The muffler caused the Piper Arrow  (?) with their rotary to crash after the internals blocked the outlet and led to power loss. It may have partially led to their withdrawal from the engine/PSRU market. To all our loss.
M

Sent from my iPad

On Nov 20, 2019, at 12:28 AM, Matt Boiteau mattboiteau@gmail.com <flyrotary@lancaironline.net> wrote:


This is the Aero Exhaust 2525XL diagram. I have one, but left it in Canada. Will bring it back with me in Jan to try at taming the exhaust again.



- Matt Boiteau

On 2019-11-19 3:23:50 PM, Charlie England ceengland7@gmail.com <flyrotary@lancaironline.net> wrote:



On Mon, Nov 18, 2019 at 11:57 PM 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

That looks a lot like a simplified version (one less turn) of a standard automotive muffler.
The Aeroturbine tries to achieve similar effect (without the flow reversals) by using venturi effect to suck part of the exhaust around and then back into the central tube.

Charlie

 
<2525.JPG>
--
Homepage:  http://www.flyrotary.com/
Archive and UnSub:   http://mail.lancaironline.net:81/lists/flyrotary/List.html
The caution about potential blockage is warranted on any engine, but obviously a greater danger with the rotary's powerful pulses.

It's worth mentioning that the Renesis' exhaust should be significantly less 'violent' than a 13B, for a couple of reasons. The exhaust has to take a 'sharp right' as it exits the combustion chamber, which helps break up the shock wave a bit, but even more importantly, the exhaust port, instead of 'snapping open' like a piston ported two stroke, opens more gradually, more like a conventional poppet valve in a piston engine.

As a FWIW on the Aeroturbine: I don't have a 2525XL to examine, but the regular 2525 (minus the 1st chamber of the XL) is a 'straight through' design. That cone on the input end is open. Drawing of the guts is on the Aeroturbine web site.
https://aeroexhaust.com/i-30497606-aero-exhaust-turbine-at2525-performance-muffler-2-5-inside-diameter-necks-aggressive-sound.html

IIRC, Tracy's been flying one on the 20B powered RV-8 for a number of years. That's what motivated me to purchase one, but it hasn't seen any exhaust gas yet.

Charlie

  Charlie,,
      Any idea how many hours Tracy has on his AeroTurbine 2525.............?
--
Kelly Troyer
Dyke Delta_"Eventually"
13B_RD1C_EC2_EM2
I don't, but I believe that it's been flying for a number of years with that muffler. Hopefully he'll see this thread & give us some 1st hand info.
Charlie
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