X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from cdptpa-omtalb.mail.rr.com ([75.180.132.121] verified) by logan.com (CommuniGate Pro SMTP 5.2.9) with ESMTP id 3272931 for flyrotary@lancaironline.net; Wed, 05 Nov 2008 12:28:46 -0500 Received-SPF: pass receiver=logan.com; client-ip=75.180.132.121; envelope-from=eanderson@carolina.rr.com Received: from computername ([75.191.186.236]) by cdptpa-omta03.mail.rr.com with ESMTP id <20081105172808.HJM24109.cdptpa-omta03.mail.rr.com@computername> for ; Wed, 5 Nov 2008 17:28:08 +0000 From: "Ed Anderson" To: "'Rotary motors in aircraft'" Subject: RE: [FlyRotary] single rotor performance Date: Wed, 5 Nov 2008 12:28:17 -0500 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_001C_01C93F41.FB874460" X-Mailer: Microsoft Office Outlook, Build 11.0.5510 In-Reply-To: Thread-Index: Ack/VInkM8X5KUCVRhKkrSAcy5WT9AAFr5QQ X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.5579 Message-Id: <20081105172808.HJM24109.cdptpa-omta03.mail.rr.com@computername> This is a multi-part message in MIME format. ------=_NextPart_000_001C_01C93F41.FB874460 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Looks Good, Richard. My experience was that at least up to the 6000-6500 rpm range that my engines produced more power with a longer runner than a shorter one. I'm certain at some point up the rpm curve at higher intake velocities that the curve would cross over to favor the shorter runner. My calculations and experience (for the two rotor) indicates a PORT to Throttle body length of around 22-26" was optimum up to around 6000 rpm depending in part on your intake porting. So 24" sounds good to me. Just for your info I idle my two rotor at around 2000 rpm. Ed Ed Anderson Rv-6A N494BW Rotary Powered Matthews, NC eanderson@carolina.rr.com http://www.andersonee.com http://members.cox.net/rogersda/rotary/configs.htm#N494BW http://www.dmack.net/mazda/index.html _____ From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Richard Sohn Sent: Wednesday, November 05, 2008 9:40 AM To: Rotary motors in aircraft Subject: [FlyRotary] single rotor performance Another step in the right direction. In deciding which way to go with the intake for the single rotor, I ran two tests. The first one with a short 8" long intake runner, and a second one with a 24" runner. The results are certainly not surprising, however, I had to check the possible impact on idle characteristic. Except for a different idle mixture setting, I was not able to detect a difference in idle characteristics at 2000RPM. There is no need for lower idle with a 3.33 : 1 gear ratio. If for any reason I want to go lower with idle, I would have to increase the fly wheel inertia. With no load on the engine it idles down to 1300RPM with the 8" runner. The long runner also resulted in a 1" higher MAP over the short runner. The 24" runner as shown in the picture will in the final configuration be at least 3" longer, because the carb has to com lower than it is now. The engine config is 12A rotor and housing using 1 1/2" p-port. The HP calculation is based on a bsfc of .5 . This is probably conservative with EGT at 1700F and mixture ratio at 14.6 . Richard Sohn N2071U __________ Information from ESET NOD32 Antivirus, version of virus signature database 3267 (20080714) __________ The message was checked by ESET NOD32 Antivirus. http://www.eset.com ------=_NextPart_000_001C_01C93F41.FB874460 Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable

Looks Good, = Richard.

 

My experience was that at least up = to the 6000-6500 rpm range that my engines produced more power with a longer = runner than a shorter one.  I’m certain at some point up the rpm = curve at higher intake velocities that the curve would cross over to favor the shorter = runner.  My calculations and experience (for the two rotor) indicates a PORT to = Throttle body length of around 22-26” was optimum up to around 6000 rpm = depending in part on your intake porting.   So 24” sounds good to = me.

 

Just for your info I idle my two = rotor at around 2000 rpm.

 

Ed

 

Ed Anderson

Rv-6A N494BW Rotary = Powered

Matthews, NC

eanderson@carolina.rr.com=

http://www.andersonee.com

http://members.cox.net/rogersda/rotary/configs.htm#N494BW

http://www.dmack.net/mazda/index.html<= font size=3D2 face=3DArial>

From: = Rotary motors in aircraft = [mailto:flyrotary@lancaironline.net] On Behalf Of Richard = Sohn
Sent: Wednesday, November = 05, 2008 9:40 AM
To: Rotary motors in aircraft
Subject: [FlyRotary] = single rotor performance

 

Another step in the right = direction.

 

In deciding which way to go with the intake for the = single rotor, I ran two tests. The first one with a short 8" long intake = runner, and a second one with a 24" runner.

The results are certainly not surprising, however, I = had to check the possible impact on idle characteristic. =

Except for a different idle mixture setting, I was = not able to detect a difference in idle characteristics at 2000RPM. There is no = need for lower idle with a 3.33 : 1 gear ratio. If for any reason I want to go = lower with idle, I would have to increase the fly wheel inertia. With no load = on the engine it idles down to 1300RPM with the 8" runner. =

The long runner also resulted in a 1" higher MAP = over the short runner.

 

The 24" runner as shown in the picture will in = the final configuration be at least 3" longer, because the carb has to = com lower than it is now.

 

The engine config is 12A rotor and housing using 1 = 1/2" p-port.

 

The HP calculation is based on a bsfc of .5 . This is probably conservative with EGT at 1700F and mixture ratio at 14.6 = .

 

Richard Sohn
N2071U



__________ Information from ESET NOD32 Antivirus, version of virus = signature database 3267 (20080714) __________

The message was checked by ESET NOD32 Antivirus.

http://www.eset.com

------=_NextPart_000_001C_01C93F41.FB874460--