X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from ispmxmta06-srv.windstream.net ([166.102.165.167] verified) by logan.com (CommuniGate Pro SMTP 5.1c.2) with ESMTP id 1321555 for flyrotary@lancaironline.net; Sat, 29 Jul 2006 07:37:05 -0400 Received-SPF: none receiver=logan.com; client-ip=166.102.165.167; envelope-from=jskmberki@alltel.net Received: from ispmxaamta04-gx.windstream.net ([71.31.134.62]) by ispmxmta06-srv.windstream.net with ESMTP id <20060729113618.EAYE4897.ispmxmta06-srv.windstream.net@ispmxaamta04-gx.windstream.net> for ; Sat, 29 Jul 2006 06:36:18 -0500 Received: from joehomepc ([71.31.134.62]) by ispmxaamta04-gx.windstream.net with SMTP id <20060729113617.SEOP8966.ispmxaamta04-gx.windstream.net@joehomepc> for ; Sat, 29 Jul 2006 06:36:17 -0500 Message-ID: <002801c6b303$19709440$01fea8c0@joehomepc> From: "Joe Berki" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: Intake design 101 Date: Sat, 29 Jul 2006 07:35:31 -0400 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0025_01C6B2E1.91FB9E90" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2800.1807 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1807 This is a multi-part message in MIME format. ------=_NextPart_000_0025_01C6B2E1.91FB9E90 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Ed, Thanks for the explanation. Now i know why they are separated. Looking = at the ports I was wondering if an oval tube shape for the runners would = be appropriate. I don't think that it is available, however. Joe ----- Original Message -----=20 From: Ed Anderson=20 To: Rotary motors in aircraft=20 Sent: Thursday, July 27, 2006 10:02 PM Subject: [FlyRotary] Re: Intake design 101 Hi Joe, Each chamber has a secondary and a primary port (six ports have an = auxiliary port which is like an additional secondary port). Even = thought a chamber has a primary and secondary, the primary and secondary = for a port normally have different intake timing. Additionally, the = opening of the intake port generally generates a very strong pulse = (residue exhaust gas bursting out of the intake when it opens). Since = the intake and secondary port of each rotor are 60 deg out of phase = timing wise with the other rotor, the pulse generated by each port can = interfere or assist with intake airflow (depending on rpm, manifold air = temp, density, etc). =20 I personally prefer to keep the intake ports separate to preclude = interference. Having said that - I have successfully flow with a system = that combined the secondary intakes and primary intakes, so what you = propose can be done. However, after trying six different intake = configurations, I have found though that I get the best performance = (for our rpm) with 4 separate tubes feeding the throttle body. Keeping = in mind I have a "Plugs Up" installation which generally gives me a bit = more room in running intake tubes. Other arrangements have been tired = and certainly work, so this is no magic formula - just based on my = personal experience.=20 Yes, the tuning (length) of the tubes should be determined by the rpm = band that you want the most airflow enhancement. It appears that a tube = length from block to Throttle body between 17 and 21" generally gives = good results. Also, avoid excessive large tubes diameters as intake = air velocity is important in stuffing the chambers and larger tubes = results in less velocity. I found that 1.25" dia tubes for the primary = and 1.5" dia tubes for the secondary works well.=20 I originally had my intakes merged into a two runner Weber style = manifold. A two port Weber style throttle body with two 2" dia intakes. = While this was the cats' meow for a racer turning 9000+ rpm, it turned = out to be disappointing in aircraft use with lower 5000-6000 rpm. = When I replace this "racers'" set up with 4 smaller dia tubes my ROC = increased by 300 fpm immediately. Unfortunately my original fuel = injection system died and I did not get to collect further data on my = old six port 1986 engine before deciding to switch to a 91 turbo block. Hope this helps. Ed Ed Anderson Rv-6A N494BW Rotary Powered Matthews, NC eanderson@carolina.rr.com http://members.cox.net/rogersda/rotary/configs.htm#N494BW 1----- Original Message -----=20 From: Joe Berki=20 To: Rotary motors in aircraft=20 Sent: Thursday, July 27, 2006 9:24 PM Subject: [FlyRotary] Intake design 101 I am using a 89 block for mock up and maybe rebuild. Looking at the = intake ports, there are two ports at the front and rear of the block = then there are two rectangular ports in the center housing close to each = other. Others have fabricated intakes using 4 tubes. I assume it is OK = for the two outboard front and rear of block to be fed by one tube while = the center two ports need to be fed individually. Is this correct? The = length of the tubes is determined by where on the rpm vs Hp band you = want to operate at? Thanks=20 Joe Berki Limo EZ -------------------------------------------------------------------------= ----- Internal Virus Database is out-of-date. Checked by AVG Free Edition. Version: 7.1.394 / Virus Database: 268.10.3/395 - Release Date: = 7/21/2006 ------=_NextPart_000_0025_01C6B2E1.91FB9E90 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Ed,
Thanks for the explanation.  Now i = know why=20 they are separated.  Looking at the ports I was wondering if an = oval tube=20 shape for the runners would be appropriate.  I don't think that it = is=20 available, however.
 
Joe
----- Original Message -----
From:=20 Ed=20 Anderson
Sent: Thursday, July 27, 2006 = 10:02=20 PM
Subject: [FlyRotary] Re: Intake = design=20 101

Hi Joe,
 
Each chamber has a secondary and a primary = port (six=20 ports have an auxiliary port which is like an additional secondary=20 port).  Even thought a chamber has a primary and secondary, the = primary=20 and secondary for a port  normally have different intake = timing. =20 Additionally, the opening of the intake port generally generates a = very strong=20 pulse (residue exhaust gas bursting out of the intake when it=20 opens).   Since the intake and secondary port of each rotor = are 60=20 deg out of phase timing wise with the other rotor, the pulse generated = by each=20 port can interfere or assist with intake airflow (depending on rpm, = manifold=20 air temp, density, etc).  
 
I personally prefer to keep the intake ports = separate to=20 preclude interference.  Having said that - I have = successfully flow=20 with a system that combined the secondary intakes and primary intakes, = so what=20 you propose can be done. However, after trying six different = intake=20 configurations,  I have found though that I get the best = performance (for=20 our rpm) with 4 separate tubes feeding the throttle body.  = Keeping in=20 mind I have a "Plugs Up" installation which generally gives me a bit = more room=20 in running intake tubes.   Other arrangements have been = tired and=20 certainly work, so this is no magic formula - just  based on = my=20 personal experience. 
 
Yes, the tuning (length) of the tubes should = be=20 determined by the rpm band that you want the most airflow = enhancement. =20 It appears that a tube length from block to Throttle body between 17 = and 21"=20 generally gives good results.  Also, avoid excessive large=20 tubes  diameters as intake air velocity is important in = stuffing the chambers and larger tubes results in  less=20 velocity.  I found that 1.25" dia tubes for the primary and 1.5" = dia=20 tubes for the secondary works well.
 
I originally had my intakes merged into a two = runner=20 Weber style manifold.  A two port Weber style throttle body with = two 2"=20 dia intakes.  While this was the cats' meow for a racer turning = 9000+=20 rpm, it turned out to be disappointing  in aircraft use with = lower=20 5000-6000 rpm.   When I replace this "racers'" set up with 4 = smaller=20 dia tubes my ROC increased by 300 fpm immediately.   = Unfortunately=20 my original fuel injection system died and I  did not get to = collect=20 further data on my old six port 1986 engine before deciding to switch = to a 91=20 turbo block.
 
Hope this helps.
 
Ed
 
Ed Anderson
Rv-6A N494BW Rotary = Powered
Matthews,=20 NC
eanderson@carolina.rr.com
http:/= /members.cox.net/rogersda/rotary/configs.htm#N494BW
 
1----- Original Message -----
From:=20 Joe=20 Berki
To: Rotary motors in = aircraft=20
Sent: Thursday, July 27, 2006 = 9:24=20 PM
Subject: [FlyRotary] Intake = design=20 101

I am using a 89 block for mock up = and maybe=20 rebuild.  Looking at the intake ports, there are two ports at = the front=20 and rear of the block then there are two rectangular ports in the = center=20 housing close to each other.  Others have fabricated intakes = using 4=20 tubes. I assume it is OK for the two outboard front and rear of = block to be=20 fed by one tube while the center two ports need to be fed = individually. Is=20 this correct?  The length of the tubes is determined by where = on the=20 rpm vs Hp band you want to operate at? Thanks
 
Joe Berki
Limo EZ

Internal Virus Database is out-of-date.
Checked by AVG Free=20 Edition.
Version: 7.1.394 / Virus Database: 268.10.3/395 - Release = Date:=20 7/21/2006
------=_NextPart_000_0025_01C6B2E1.91FB9E90--