X-Junk-Score: 0 [] X-Cloudmark-Score: 0 [] X-Cloudmark-Analysis: v=2.3 cv=G+5i7Os5 c=1 sm=1 tr=0 a=2f/BrsI30kxfi1RG7K8GXg==:117 a=jpOVt7BSZ2e4Z31A5e1TngXxSK0=:19 a=x7bEGLp0ZPQA:10 a=DDNF8ybvv5wA:10 a=xqWC_Br6kY4A:10 a=J70Eh1EUuV4A:10 a=_EeEMxcBAAAA:8 a=Ia-xEzejAAAA:8 a=pGLkceISAAAA:8 a=o1OHuDzbAAAA:8 a=_6GpL_ENAAAA:8 a=7g1VtSJxAAAA:8 a=YbOZEG0irrj1z_NaREoA:9 a=WWOPCwnXjFgbMyPq:21 a=PGNd-LLYjo1zhVGf:21 a=CjuIK1q_8ugA:10 a=Qa1je4BO31QA:10 a=5UeK9suJl1gA:10 a=gvSQh4r-fQ0A:10 a=poIJEapUpkBWyUW0hpIA:9 a=0xyZ837mms6FucEd:21 a=vctm-ZDz3VYkRoCX:21 a=u89aDj7viRPZmAAd:21 a=_W_S_7VecoQA:10 a=syqr5EOPB93U0NEwqYpB:22 a=Urk15JJjZg1Xo0ryW_k8:22 a=5YQ6H4ZxyGn-KoBYtt8s:22 a=grOzbf7U_OpcSX4AJOnl:22 From: "Le Roux Breytenbach breytenbachleroux@gmail.com" Received: from mail-ed1-f44.google.com ([209.85.208.44] verified) by logan.com (CommuniGate Pro SMTP 6.2.14) with ESMTPS id 12952354 for flyrotary@lancaironline.net; Thu, 12 Sep 2019 22:47:30 -0400 Received-SPF: pass receiver=logan.com; client-ip=209.85.208.44; envelope-from=breytenbachleroux@gmail.com Received: by mail-ed1-f44.google.com with SMTP id a23so23484851edv.5 for ; Thu, 12 Sep 2019 19:47:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:subject:thread-topic:thread-index:date:message-id :references:in-reply-to:accept-language:content-language :mime-version; bh=2lKu2o4EbxVhgTOiroBR9kM6URemBXh+IAVyeyjlNsI=; b=pz1h8Naa3rcXduYc3SW86BaI6+BFuqfHy7Bt1tTeRtBcoQeP11doqQ/NE8beXq9vDq yHOHLA4a/Vc7KojcSPiz32+b6ma3inWmKdNPP9kgFEi8EQiD2gRSlQu1IX+IVCNvZOLG 4k/G873O8VlSlxedG2tr3Y1fgRUGzy99T5i9ZkxSnpLZAvp7ljNjnDCc8C7d5CaRUsuJ RMPforRhNQE0O1kZCO43+MlA0fgSBSMs5fTkcg1OKUfiOs6iCa7OTyLR8t4tUWdzyjcG L7iVUZzGuSpefiLxBR6uyUmi/+P7linYvJM/jGrXb1WvT6qE127cJcirJyMWdkhArRzP A/wA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:subject:thread-topic:thread-index:date :message-id:references:in-reply-to:accept-language:content-language :mime-version; bh=2lKu2o4EbxVhgTOiroBR9kM6URemBXh+IAVyeyjlNsI=; b=bgbLFs++j/4jLXDd75Zxl1AKi3kaAK3AJVLmBvdBDPAymPLWMQQN7xCULXrBdhTPTz fKrqtJ2+fP3FAnJRLGXPugOSvr5zE+9DcwlwKpn+6zHiRa0f7xW3X8W8Nx9zXiHjA9Nb u5E0U7h89dHpjJw7dKc1NiiNirvTMEV61bi7bC5w6vEICnMb1vBRgRottixPHZLBAbxa KspHLJ9TYIKiFAQqQtf2x/30mroC8eDLa0MueI2mXJ892Yfzq5zCkiuI7nmHhNYmDqj7 coSrdgRhf0bIARSdCcZhzVCcaibyibeAmsQe8xHHv+fqG5FSaILNbSvzecTrNyYdgkt/ vVVQ== X-Gm-Message-State: APjAAAWuGbPEddKBZH4VO6vr7HVvYZh96dkaUk1JsVDz7VGP8sjdPcVz MvzNyulgl2B/bRk/ZOzihAUrSzpD X-Google-Smtp-Source: APXvYqyuQj8KkVvJBSPrTNrBU/d7ePxeB2N6ayHFpmEMpmNqyExHFQR0o/+7WnnCZ7XgLPPpXfm4GQ== X-Received: by 2002:a17:906:7c55:: with SMTP id g21mr36650363ejp.177.1568342833672; Thu, 12 Sep 2019 19:47:13 -0700 (PDT) Return-Path: Received: from SN1PR12MB2398.namprd12.prod.outlook.com ([2603:1036:802:6::5]) by smtp.gmail.com with ESMTPSA id n9sm5124174edq.54.2019.09.12.19.47.12 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 12 Sep 2019 19:47:13 -0700 (PDT) To: Rotary motors in aircraft Subject: Re: [FlyRotary] Re: Intake progress Thread-Topic: [FlyRotary] Re: Intake progress Thread-Index: ATkyNTItnom20BnJgBySZC8LUBf8sLhvSIFj X-MS-Exchange-MessageSentRepresentingType: 1 Date: Fri, 13 Sep 2019 02:47:10 +0000 Message-ID: References: In-Reply-To: Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-Exchange-Organization-SCL: -1 X-MS-TNEF-Correlator: X-MS-Exchange-Organization-RecordReviewCfmType: 0 Content-Type: multipart/alternative; boundary="_000_SN1PR12MB23989B2D23BCB53CDEEAA345FDB30SN1PR12MB2398namp_" MIME-Version: 1.0 --_000_SN1PR12MB23989B2D23BCB53CDEEAA345FDB30SN1PR12MB2398namp_ Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Charlie: I designed my intake plenum out of 125 mm (5 inch) irrigation pipe= as a mould and covered it (rolled) it with 8 layers of bidirectional glass= cloth. The end cap on intake side for the throttlebody is 8 mm fenolic sheet that = is covered with glass cloth to use as a hard point to bolt the TB (throttle= body)The other end cap is roundshaped to optimize waves "bouncing" inside t= he plenum. The total volume of the intake runners from the rotary surface to the bell = mouths must be calculated. The volume of the intake plenum must be 2,5 x intake volume if the intake r= unners. I has p ported my 13B with 2 x 45 mm inside diameter runners. For the best VE ( volumetric efficiency) the "proof is in the poeding " to = tunned the length of the intake runners. Don't know your setup , but for p port 13B it is somewhere between 21 and 2= 4 inch intake runners. Has build the plenum so that it can bolt open to work and inspections insid= e. I have build my own intake bell mouth velocity stacks and covered it with c= arbon fiber braided sleaves. The whole plenum box can be slide "up and down" on the runners to tunned it= on run ups for final testing for VE Still building and no testing has been done at this stage Will post some photos for comments, has to crop them on pc before mailing f= or size tomorrow morning As Lynn always say "I could be wrong" Le Roux Get Outlook for iOS ________________________________ From: Rotary motors in aircraft on behalf of = Charlie England ceengland7@gmail.com Sent: Friday, September 13, 2019 3:20 AM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Intake progress My '1st draft' (before the box) was a 6 " aluminum tube (irrigation tubing) that I re-contoured into a wavy contraption a little closer to flat where the bellmouths faced. 1/4" aluminum plate for the ends. That looked questionable, so I went worse. :-( I would expect a round tube with 1/4" end plates to handle the loads, but I haven't proven it. On intake size, most of the stuff I've read addressing both induction air and cooling talks about taking in every bit of the air needed and no more, because trying to take in more than needed either adds drag as the extra air flows through the plane's systems, or adds drag due to spillage & turbulence around the lips of the intake. Achieving that goal is a pretty high bar, though, given the wide speed variations of fast a/c. Bernie Kerr (Hi Bernie, are you still watching?) used to talk about 'external diffusion' (as opposed to internal diffusion, where the air enters the duct at system airspeed and slows within the duct), which apparently works well by slowing the air in front of the duct and minimizes spillage losses by optimizing the lip of the entrance. Apparently has the additional advantage of making duct shape less critical. You can calculate the volume of air the engine ingests per second, then calculate the intake size required to take in that volume of air per second, all at expected operational speed. I suspect that's what Tracy did. I chose the easy (lazy) way out & sized the inlet the same as the throttle body/total intake tube area, and am willing to accept 'external diffusion' spillage at speed. Or, like Lynn often says, I could be wrong. :-) Charlie On 9/12/2019 5:47 PM, Finn Lassen finn.lassen@verizon.net wrote: > Thanks Charlie, > > I was planning on using 1/4" plywood wrapped in fiberglass. (Tracy had > warned me.) I do have a length of 6" OD 0.035 SS pipe, but what about > the ends (or end opposite throttle body)? > I can weld SS with my Henrob, but no success with aluminum. Also the > curve of the pipe would make me shorten the intake runners a bit to > make room around the bell mouths. > > I started reading the grapeape-inductionsystems.pdf paper and realized > that's going to take quite a bit of study and research. Like what is > the VE (Volumetric Efficiency) of a Renesis? > > Seems I start with the best intentions to design the optimal > installation and end up copping out and doing "looks about right" or > "what he did". > > Like, I have no clue how big my air intake opening should be. Just the > size of the throttle body? Tracy mentioned something about the air > intake should gradually open up to the size of the throttle body. I > should now have plenty of room in the left cheek for a straight run > from near the prop to the throttle body mounted on the plenum (shoe box). > > Finn > > On 9/12/2019 5:26 PM, Charlie England ceengland7@gmail.com wrote: >> Like most people's dad used to say, "Don't do as I do (did); do as I >> say." :-) >> >> Tracy looked at my box after it was built & pointed out what I should >> have considered: those big flat (thin) aluminum panels won't survive >> intake pressure waves. I knew better, but that part of my mind had >> gone on break during the entire construction of the box. Car makers >> don't waste aluminum making cast 1/4" thick plenums just to get rid >> of surplus aluminum. :-) >> >> That box is now lined with 1/4" plywood and fiberglass, and weighs >> far too much. I'm doubtful that it will be a flight item. >> >> I'd suggest doing what Tracy did, & start with plywood/fiberglass, or >> use a 4"-6" round aluminum tube for the plenum. I can probably dig up >> some 6" if you want to try it, or check local farm-market >> publications down there for surplus irrigation pipe. >> >> I never did find any tube length/plenum sizing advice for the rotary >> that I trusted. Very few Renesis car guys ever touch the stock >> manifold, since it would be very difficult to improve on Mazda's >> design for a car. >> >> Charlie >> >> On 9/12/2019 12:02 PM, Finn Lassen finn.lassen@verizon.net wrote: >>> 6 1/2 years later I'm about to do the same and would like to ask the >>> same question before I make my "shoe box": >>> >>> "I'm curious about how others have adapted the common Helmholtz >>> intake tuning formulas to the rotary. Would anyone care to 'show >>> their (math) work'?" >>> >>> Rather than building it as big as possible, I'd like to know if >>> there is an optimal size. >>> >>> Finn >>> >>> Charlie's photo: >>> >>> >>> >>> On 2/17/2013 3:41 PM, Charlie England wrote: >>>> >>>> Now that everyone's awake again, I thought I'd send a pic of my >>>> intake progress (RV-7 Renesis with James Lyc cowl). I played with a >>>> couple of different materials for the bell mouths. I tried gluing >>>> up some 1/4" plexi from an old windshield, but used super glue >>>> instead of proper plexi cement (which I wasn't able to find locally >>>> in a hurry). The 1st try popped apart on the lathe; the 2nd turned >>>> out ok. Next effort was with 3/4" MDF (medium density fiberboard). >>>> That went well, until I put a little too much side pressure on the >>>> ring (homemade cutting tool) after undercutting the center section. >>>> Overall tube lengths will be ~11 3/4" block surface to bell ends. >>>> The plenum is *much* bigger than most tuning sites recommend. I >>>> figure that I can experiment with plenum size by just stuffing it >>>> with rigid foam to take up some volume, if needed. Going the other >>>> way wouldn't be so easy. :-) >>>> >>>> Since I don't have Mark's TIG skills, I thought I'd ask what others >>>> have used in joining thin wall tubing to 1/4" aluminum plate. >>>> Aluminum brazing rod? High temp epoxy? JB weld? I do intend to add >>>> bracing from the plate to the plenum assembly to take some of the >>>> cantilever & vibration stress off the tubes. >>>> >>>> I'm using this length and concept because Tracy has had great luck >>>> with both HP & BSFC on his Renesis with a similar configuration. >>>> However, I'm curious about how others have adapted the common >>>> Helmholtz intake tuning formulas to the rotary. Would anyone care >>>> to 'show their (math) work'? Renesis users would be better for me, >>>> but any calcs would do. When I tried to adapt the common formulas >>>> to a rotary, I was getting 'interesting' results, so I'd like to >>>> know if I got lost somewhere while trying to plug rotary 'valve' >>>> timing into the formulas. >>>> >>>> Charlie >>>> (Sorry for the sideways iphone pic; I guess you can pretend that >>>> you're looking down on it...) >>> --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus -- Homepage: http://www.flyrotary.com/ Archive and UnSub: http://mail.lancaironline.net:81/lists/flyrotary/List.ht= ml --_000_SN1PR12MB23989B2D23BCB53CDEEAA345FDB30SN1PR12MB2398namp_ Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable
Charlie: I designed my intake plenum out of = 125 mm (5 inch) irrigation pipe as a mould and covered it (rolled) it with = 8 layers of bidirectional glass cloth.
The end cap on intake side for the throttleb= ody is 8 mm fenolic sheet that is covered with glass cloth to use as a hard= point to bolt the TB (throttlebody)The other end cap is roundshaped to opt= imize waves "bouncing" inside the plenum.
The total volume of the intake runners from = the rotary surface to the bell mouths must be calculated.
The volume of the intake plenum must be 2,5 = x intake volume if the intake runners.
I has p ported my 13B with 2 x 45 mm inside = diameter runners.
For the best VE ( volumetric efficiency) the= "proof is in the poeding " to tunned the length of the intake ru= nners.
Don't know your setup , but for p port 13B i= t is somewhere between 21 and 24 inch intake runners.
Has build the plenum so that it can bolt ope= n to work and inspections inside.
I have build my own intake bell mouth veloci= ty stacks and covered it with carbon fiber braided sleaves.
The whole plenum box can be slide "up a= nd down" on the runners to tunned it on run ups for final testing for = VE
Still building and no testing has been done = at this stage
Will post some photos for comments, has to c= rop them on pc before mailing for size tomorrow morning

As Lynn always say "I could be wrong&qu= ot;

Le Roux


Get Outlook for iOS
 
From: Rotary motors in airc= raft <flyrotary@lancaironline.net> on behalf of Charlie England ceeng= land7@gmail.com <flyrotary@lancaironline.net>
Sent: Friday, September 13, 2019 3:20 AM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: Intake progress
 
My '1st draft' (before the box) was a 6 " aluminum tube (irrigation tubing) that I re-contoured into a wavy contraption a little closer to
flat where the bellmouths faced. 1/4" aluminum plate for the ends. Tha= t
looked questionable, so I went worse. :-(   I would expect a roun= d tube
with 1/4" end plates to handle the loads, but I haven't proven it.
On intake size, most of the stuff I've read addressing both induction
air and cooling talks about taking in every bit of the air needed and no more, because trying to take in more than needed either adds drag as the extra air flows through the plane's systems, or adds drag due to
spillage & turbulence around the lips of the intake. Achieving that goa= l
is a pretty high bar, though, given the wide speed variations of fast
a/c. Bernie Kerr (Hi Bernie, are you still watching?) used to talk about 'external diffusion' (as opposed to internal diffusion, where the air
enters the duct at system airspeed and slows within the duct), which
apparently works well by slowing the air in front of the duct and
minimizes spillage losses by optimizing the lip of the entrance.
Apparently has the additional advantage of making duct shape less critical.=

You can calculate the volume of air the engine ingests per second, then calculate the intake size required to take in that volume of air per
second, all at expected operational speed. I suspect that's what Tracy
did. I chose the easy (lazy) way out & sized the inlet the same as = ; the
throttle body/total intake tube area, and am willing to accept 'external diffusion' spillage at speed.

Or, like Lynn often says, I could be wrong. :-)

Charlie

On 9/12/2019 5:47 PM, Finn Lassen finn.lassen@verizon.net wrote:
> Thanks Charlie,
>
> I was planning on using 1/4" plywood wrapped in fiberglass. (Trac= y had
> warned me.) I do have a length of 6" OD 0.035 SS pipe, but what a= bout
> the ends (or end opposite throttle body)?
> I can weld SS with my Henrob, but no success with aluminum. Also the <= br> > curve of the pipe would make me shorten the intake runners a bit to > make room around the bell mouths.
>
> I started reading the grapeape-inductionsystems.pdf paper and realized=
> that's going to take quite a bit of study and research. Like what is <= br> > the VE (Volumetric Efficiency) of a Renesis?
>
> Seems I start with the best intentions to design the optimal
> installation and end up copping out and doing "looks about right&= quot; or
> "what he did".
>
> Like, I have no clue how big my air intake opening should be. Just the=
> size of the throttle body? Tracy mentioned something about the air > intake should gradually open up to the size of the throttle body. I > should now have plenty of room in the left cheek for a straight run > from near the prop to the throttle body mounted on the plenum (shoe bo= x).
>
> Finn
>
> On 9/12/2019 5:26 PM, Charlie England ceengland7@gmail.com wrote:
>> Like most people's dad used to say, "Don't do as I do (did); = do as I
>> say." :-)
>>
>> Tracy looked at my box after it was built & pointed out what I= should
>> have considered: those big flat (thin) aluminum panels won't survi= ve
>> intake pressure waves. I knew better, but that part of my mind had=
>> gone on break during the entire construction of the box. Car maker= s
>> don't waste aluminum making cast 1/4" thick plenums just to g= et rid
>> of surplus aluminum. :-)
>>
>> That box is now lined with 1/4" plywood and fiberglass, and w= eighs
>> far too much. I'm doubtful that it will be a flight item.
>>
>> I'd suggest doing what Tracy did, & start with plywood/fibergl= ass, or
>> use a 4"-6" round aluminum tube for the plenum. I can pr= obably dig up
>> some 6" if you want to try it, or check local farm-market >> publications down there for surplus irrigation pipe.
>>
>> I never did find any tube length/plenum sizing advice for the rota= ry
>> that I trusted. Very few Renesis car guys ever touch the stock >> manifold, since it would be very difficult to improve on Mazda's <= br> >> design for a car.
>>
>> Charlie
>>
>> On 9/12/2019 12:02 PM, Finn Lassen finn.lassen@verizon.net wrote: =
>>> 6 1/2 years later I'm about to do the same and would like to a= sk the
>>> same question before I make my "shoe box":
>>>
>>> "I'm curious about how others have adapted the common Hel= mholtz
>>> intake tuning formulas to the rotary. Would anyone care to 'sh= ow
>>> their (math) work'?"
>>>
>>> Rather than building it as big as possible, I'd like to know i= f
>>> there is an optimal size.
>>>
>>> Finn
>>>
>>> Charlie's photo:
>>>
>>>
>>>
>>> On 2/17/2013 3:41 PM, Charlie England wrote:
>>>>
>>>> Now that everyone's awake again, I thought I'd send a pic = of my
>>>> intake progress (RV-7 Renesis with James Lyc cowl). I play= ed with a
>>>> couple of different materials for the bell mouths. I tried= gluing
>>>> up some 1/4" plexi from an old windshield, but used s= uper glue
>>>> instead of proper plexi cement (which I wasn't able to fin= d locally
>>>> in a hurry). The 1st try popped apart on the lathe; the 2n= d turned
>>>> out ok. Next effort was with 3/4" MDF (medium density= fiberboard).
>>>> That went well, until I put a little too much side pressur= e on the
>>>> ring (homemade cutting tool) after undercutting the center= section.
>>>> Overall tube lengths will be ~11 3/4" block surface t= o bell ends.
>>>> The plenum is *much* bigger than most tuning sites recomme= nd. I
>>>> figure that I can experiment with plenum size by just stuf= fing it
>>>> with rigid foam to take up some volume, if needed. Going t= he other
>>>> way wouldn't be so easy. :-)
>>>>
>>>> Since I don't have Mark's TIG skills, I thought I'd ask wh= at others
>>>> have used in joining thin wall tubing to 1/4" aluminu= m plate.
>>>> Aluminum brazing rod? High temp epoxy? JB weld? I do inten= d to add
>>>> bracing from the plate to the plenum assembly to take some= of the
>>>> cantilever & vibration stress off the tubes.
>>>>
>>>> I'm using this length and concept because Tracy has had gr= eat luck
>>>> with both HP & BSFC on his Renesis with a similar conf= iguration.
>>>> However, I'm curious about how others have adapted the com= mon
>>>> Helmholtz intake tuning formulas to the rotary. Would anyo= ne care
>>>> to 'show their (math) work'? Renesis users would be better= for me,
>>>> but any calcs would do. When I tried to adapt the common f= ormulas
>>>> to a rotary, I was getting 'interesting' results, so I'd l= ike to
>>>> know if I got lost somewhere while trying to plug rotary '= valve'
>>>> timing into the formulas.
>>>>
>>>> Charlie
>>>> (Sorry for the sideways iphone pic; I guess you can preten= d that
>>>> you're looking down on it...)
>>>


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