X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from cdptpa-omtalb.mail.rr.com ([75.180.132.122] verified) by logan.com (CommuniGate Pro SMTP 5.2.11) with ESMTP id 3407036 for flyrotary@lancaironline.net; Thu, 01 Jan 2009 14:09:13 -0500 Received-SPF: pass receiver=logan.com; client-ip=75.180.132.122; envelope-from=eanderson@carolina.rr.com Received: from computername ([75.191.186.236]) by cdptpa-omta01.mail.rr.com with ESMTP id <20090101190835.VMVA7108.cdptpa-omta01.mail.rr.com@computername> for ; Thu, 1 Jan 2009 19:08:35 +0000 From: "Ed Anderson" To: "'Rotary motors in aircraft'" Subject: RE: [FlyRotary] Re: Activity...... Date: Thu, 1 Jan 2009 14:08:39 -0500 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_002B_01C96C1A.756E1D30" X-Mailer: Microsoft Office Outlook, Build 11.0.5510 Thread-Index: AclsMlEBq/8oN6d0S5SdniLlALB7kgACUPmA X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.5579 In-Reply-To: Message-Id: <20090101190835.VMVA7108.cdptpa-omta01.mail.rr.com@computername> This is a multi-part message in MIME format. ------=_NextPart_000_002B_01C96C1A.756E1D30 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Dennis, I'll try and give you a more "detailed" review of you analysis and approach in a short while (I have to dig up a drawing of the Renesis 4 port intake to look at). However, I seem to recall that there is a valve in the air passages of the intake that rotates open or closed depending of some engine load variables. IF my memory is correct, this value in effect halves (or doubles depending on which runner you are using for reference) the distance the pulse has to travel from port of one rotor to port of the second rotor. At the right rpm range the value closes forcing the pulse to travel the shorter distance (or else it opens at the lower RPM range to make the pulse travel a longer circuit - or vice versa - I have to look and see if the Renesis even has such a valve - the older N/A 13Bs did have the value in order to change the effective length of the intake runners. I can not tell from my hasty look at your e mails whether you took that factor (the valve changing the effective length of the runner) into consideration or indeed, if the Renesis even has one. ? Will get back to you shortly 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 Dennis Haverlah Sent: Thursday, January 01, 2009 11:59 AM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Activity...... OK - I'll try to stirrup some reflective comment on the list. I'm in the middle of trying to design a new intake for my RX-8 Renesis powered RV-7A I've been reading the tuned intake discussion posts from 2004 and 2005. FAW theory etc. I've tried to apply the theories to the Mazda RX-8 4 port intake to see how it works and make sure it agreed with the theories. No Luck!!? My measurements of the cast aluminum intake show primary runners are 12.5 in. long + 2.5 inch to the center of the chamber where the intake runners from rotor 1 interact with rotor 2's intake runners. Add 3 inches at the other end ( engine flange) for the distance from the manifold flange to the center of the intake at the rotor face and the total intake is 18.0 inches. The secondaries are 1/2 inch longer at 18.5 inches. It appears they are using the FAW wave created as Rotor #1 intake opens to travel through the intake tubes to Rotor #2. Total distance from rotor #1 to rotor #2 is 36 in. for primary runners and 37 in. for secondary runners. Ed's post of Aug. 26,04 indicated a "E" shaft rotation of 93 deg. between Rotor #1 opening and Rotor #2 closing. I measured the angle on an old engine and agree. The pulse from rotor #1 needs some opening to exit and at rotor #2 you must have some opening to enter the rotor. I'll guess this is a total of 10 deg. Hence we have about 83 deg of "E" shaft rotation time for the pulse to travel from rotor #1 to rotor #2. I want to design my intake for max. HP at 6750 rpm. 6750/60 = 112.5 rps; 1/112.5 = 0.008888rev/sec or for 360 deg rotation of the "E" shaft it takes 8.888ms. The time for 83 deg of "E" shaft rotation would be 8.888ms*83deg/360deg = 2.05ms. (the time available for the pulse to travel from rotor #1 to #2.) speed of sound = 1100fps or 1.1f/ms*12 = 13.2 in/ms. So 13.2in/ms * 2.05 ms = 26.4 inch from rotor #1 to #2. My problem is this is already 5 in./ intake shorter than the RX-8 4 port intake. If I assume their intake is designed for 8500 rpm the calculation indicates a runner length of 21.3 inches is needed between rotor 31 and #2. I measured the RX-8 cast al. intake to be 18 in * 2 = 36 in . To me it appears I do not understand how the RX-8 intake really works!! Anyone have any ideas or find an error with the logic? Going FAW crazy!! Dennis H. __________ 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_002B_01C96C1A.756E1D30 Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable

Dennis,

=

 

I’ll try and give you a more = “detailed” review of you analysis and approach in a short while (I have to dig up a drawing of the Renesis 4 port intake to look at).  However, I seem = to recall that there is a valve in the air passages of the intake that = rotates open or closed depending of some engine load variables.  IF my = memory is correct, this value in effect halves (or doubles depending on which = runner you are using for reference) the distance the pulse has to travel from port = of one rotor to port of the second rotor.  At the right rpm range the = value closes forcing the pulse to travel the shorter distance (or else it = opens at the lower RPM range to make the pulse travel a longer circuit – or = vice versa – I have to look and see if the Renesis even has such a = valve – the older N/A 13Bs did have the value in order to change the effective = length of the intake runners.

 

I can not tell from my hasty look = at your e mails whether you took that factor (the valve changing the effective = length of the runner)  into consideration or indeed, if the Renesis even = has one. ?

 

Will get back to you shortly =

 

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 Dennis Haverlah
Sent: Thursday, January = 01, 2009 11:59 AM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: Activity......

 

OK - I'll try to stirrup some reflective = comment on the list.

I'm in the middle of trying to design a new intake for my RX-8 Renesis = powered RV-7A
I've been reading the tuned intake discussion posts from 2004 and = 2005.  FAW theory etc.  I've tried
to apply the theories to the Mazda RX-8  4 port intake to see how = it works and make sure it
agreed with the theories.  No Luck!!? 

My measurements of the cast aluminum intake show primary runners are = 12.5 in. long + 2.5 inch to the center of the chamber
where the intake runners from rotor 1 interact with rotor 2's intake runners.  Add 3 inches at the other end ( engine flange) for the = distance from the
manifold flange to the center of the intake at the rotor face and the = total intake is 18.0 inches.  The secondaries are 1/2 inch longer at 18.5 inches. 

It appears they are using the FAW wave created as Rotor #1 intake opens = to travel through the intake tubes to Rotor #2.  Total distance  = from rotor
#1 to rotor #2 is 36 in. for primary runners and 37 in. for secondary = runners.

Ed's post of Aug. 26,04 indicated a "E" shaft rotation of 93 = deg. between Rotor #1 opening and Rotor #2 closing.  I measured the = angle on an old engine and agree. 
The pulse from rotor #1 needs some opening to exit and at rotor #2 you = must have some opening to enter the rotor.  I'll guess this is a total = of 10 deg.  Hence we have about 83 deg of  "E" shaft = rotation time for the pulse to travel from rotor #1 to rotor #2.

I want to design my intake for max. HP at 6750 rpm.  6750/60 =3D = 112.5 rps; 1/112.5 =3D 0.008888rev/sec or for 360 deg rotation of the "E" = shaft it takes 8.888ms.
The time for 83 deg of "E" shaft rotation would be 8.888ms*83deg/360deg =3D 2.05ms. (the time available for the pulse to = travel from rotor #1 to #2.)
speed of sound =3D 1100fps or 1.1f/ms*12 =3D 13.2 in/ms.  So = 13.2in/ms *  2.05 ms =3D 26.4 inch from rotor #1 to #2.  My problem is this is = already 5 in./ intake shorter than the RX-8 4 port intake.  If I = assume their intake is designed for 8500 rpm the calculation indicates a runner = length of 21.3 inches is needed between rotor
31 and #2.  I measured the RX-8 cast al. intake to be 18 in * 2 = =3D 36 in .

To me it appears I do not understand how the RX-8 intake really = works!!  Anyone have any ideas or find an error with the logic?

Going FAW crazy!!

Dennis H.



 



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

The message was checked by ESET NOD32 Antivirus.

http://www.eset.com

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