X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: <13brv3@bellsouth.net> Received: from imf21aec.mail.bellsouth.net ([205.152.59.69] verified) by logan.com (CommuniGate Pro SMTP 4.3c5) with ESMTP id 936523 for flyrotary@lancaironline.net; Sun, 08 May 2005 13:08:21 -0400 Received-SPF: pass receiver=logan.com; client-ip=205.152.59.69; envelope-from=13brv3@bellsouth.net Received: from rd ([65.6.194.9]) by imf21aec.mail.bellsouth.net (InterMail vM.5.01.06.11 201-253-122-130-111-20040605) with ESMTP id <20050508170735.YRTV23609.imf21aec.mail.bellsouth.net@rd> for ; Sun, 8 May 2005 13:07:35 -0400 From: "Russell Duffy" <13brv3@bellsouth.net> To: "'Rotary motors in aircraft'" Subject: RE: [FlyRotary] Re: 4-port intake measurements Date: Sun, 8 May 2005 12:07:39 -0500 Message-ID: <000501c553f0$70d6d0f0$6101a8c0@rd> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0006_01C553C6.8800C8F0" X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook, Build 10.0.6626 Importance: Normal In-Reply-To: X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2527 This is a multi-part message in MIME format. ------=_NextPart_000_0006_01C553C6.8800C8F0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable When I combined my primary and secondary on one of my intake designs I = used a 1.75" dia tube, so sounds like your dimensions closely agree. I = currently have a 1 1/2 and 1 1/4 for the secondary and primary respectively. So = that gives me a total of 2.99 sq inch runner area per rotor. So approx .45 sq inches more per rotor than you currently have, so I would say your = current design could be restrictive. =20 =20 Thanks Ed, That's pretty much my conclusion too. While it's certainly making good power, it could clearly be better, so it's probably worth = the hassle of making another intake. =20 =20 I'm not sure if we ever cleared up this business about whether you need = a single TB big to allow for both rotors, or just one at a time. That was = at the heart of the Ellison debate. Interestingly, if you add the sizes of = the ports on both rotors, it comes to an equivalent tube of about 63mm ID, = which is right in line with the recent discussion of TB sizes. =20 =20 Here's another wacky idea for your entertainment- I'm familiar with the scavenging concept used in exhaust systems. For one bank of a V-8, you start with 4 pipes, then combine them to two bigger pipes, and finally = one even bigger pipe. The thought is that active flow from one pipe is = creating a suction on the others to help pull out exhaust of a cylinder that's = almost done with it's exhaust cycle. =20 =20 Will this work in reverse? It almost seems like it would to me. What = would happen if you start with two primaries, and two secondaries, then = combine them to make two larger pipes (one for each rotor), then combine again = for a single larger pipe with a TB on the end of it? =20 =20 Cheers, Rusty (more power Scotty) ------=_NextPart_000_0006_01C553C6.8800C8F0 Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Message
When I combined my = primary and=20 secondary on one of my intake designs I used a 1.75" dia tube, = so sounds=20 like your dimensions closely agree.  I currently have a 1 1/2 and 1 = 1/4 for=20 the secondary and primary respectively.  So that gives me a total = of 2.99=20 sq inch runner area per rotor. So approx .45 sq inches more per rotor = than you=20 currently have, so I would say your current design could be=20 restrictive.
 
 
Thanks=20 Ed,  That's pretty much my conclusion too.  While it's = certainly=20 making good power, it could clearly be better, so it's = probably worth=20 the hassle of making another intake.  
 
I'm not sure=20 if we ever cleared up this business about whether you need a single = TB big=20 to allow for both rotors, or just one at a time.  That was at = the=20 heart of the Ellison debate.  Interestingly, if you add the = sizes of=20 the ports on both rotors, it comes to an equivalent tube of about 63mm = ID, which=20 is right in line with the recent discussion of TB=20 sizes.  
 
Here's=20 another wacky idea for your entertainment- I'm familiar with = the scavenging=20 concept used in exhaust systems.  For one bank of a V-8, = you=20 start with 4 pipes, then combine them to two bigger pipes, and=20 finally one even bigger pipe.  The thought is that active = flow=20 from one pipe is creating a suction on the others to help pull out = exhaust of a=20 cylinder that's almost done with it's exhaust cycle.  =
 
Will this=20 work in reverse?  It almost seems like it would to = me.  What=20 would happen if you start with two primaries, and two secondaries, = then=20 combine them to make two larger pipes (one for each rotor), then combine = again=20 for a single larger pipe with a TB on the end of=20 it?     
 
Cheers,
Rusty (more=20 power Scotty)
------=_NextPart_000_0006_01C553C6.8800C8F0--