X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from access.aic-fl.com ([204.49.76.2] verified) by logan.com (CommuniGate Pro SMTP 5.0.9) with ESMTP id 1117364 for flyrotary@lancaironline.net; Wed, 17 May 2006 13:19:27 -0400 Received-SPF: none receiver=logan.com; client-ip=204.49.76.2; envelope-from=unicorn@gdsys.net Received: from b9k4u9 (unverified [204.49.76.189]) by access.aic-fl.com (Rockliffe SMTPRA 4.5.6) with SMTP id for ; Wed, 17 May 2006 12:16:39 -0500 Message-ID: <001001c679e7$f879b590$bd4c31cc@b9k4u9> From: "Richard Sohn" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: Date: Wed, 17 May 2006 12:27:21 -0700 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0007_01C679AD.3EB5E910" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.2869 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2869 This is a multi-part message in MIME format. ------=_NextPart_000_0007_01C679AD.3EB5E910 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable ----- Original Message -----=20 From: Al Gietzen=20 To: Rotary motors in aircraft=20 Sent: Wednesday, May 17, 2006 6:20 AM Subject: [FlyRotary] Re:=20 Richard, are you saying that the metering oil nozzles that inject oil = into the combustion chamber should have a vacuum line attached to the = top opening of the injector nozzle? I recall a discussion some time ago = where I thought you said that it was OK for those connections to be open = to the atmosphere. I would say that it is OK for them to be open to the atmosphere. The = reason to connect them to the manifold is to get filtered air, and to = modulate the differential pressure across the valve. At low throttle = there would be low pressure in both manifold and rotor housing. I have = no idea of the full story of the pressure dynamics over the throttle = range. If the vacuum line is disconnected, the oil being pumped into the = rotor housing drop by drop is not spread cross wise along the apex seal. = Therefore, the oil will do next to nothing in regard to cooling or = lubricating the apex seal.=20 Based on experience of others, this appears to be an overstatement. = Rotories have run thousands of hours with no air to the nozzles. There = may be some evidence of wear patterns indicating that the tip seal = travels some distance (maybe 4-5") from the point of injection before = the oil spreads to the ends of the seals, but I'm not aware of any = direct comparison wear with and without the air flow. Maybe some of our = racing friends can have some input on this. Al Certainly, Al, nobody seems to know how much good that top lube does, = if any. Richard Sohn N-2071U ------=_NextPart_000_0007_01C679AD.3EB5E910 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
 
----- Original Message -----
From:=20 Al = Gietzen=20
Sent: Wednesday, May 17, 2006 = 6:20=20 AM
Subject: [FlyRotary] Re:

 

Richard,=20 are you saying that the metering oil nozzles that inject oil into the=20 combustion chamber should have a vacuum line attached to the top = opening of=20 the injector nozzle?  I recall a discussion some time ago where I = thought=20 you said that it was OK for those connections to be open to the=20 atmosphere.

 

I would = say that it=20 is OK for them to be open to the atmosphere.  The reason to = connect them=20 to the manifold is to get filtered air, and to modulate the = differential=20 pressure across the valve. At low throttle there would be low pressure = in both=20 manifold and rotor housing. I have no idea of the full story of the = pressure=20 dynamics over the throttle range.

 

If the vacuum line is=20 disconnected, the oil being pumped into the rotor housing drop by drop = is not=20 spread cross wise along the apex seal. Therefore, the oil will do next = to=20 nothing in regard to cooling or lubricating the apex seal. =

 

Based on = experience=20 of others, this appears to be an overstatement.  Rotories have = run=20 thousands of hours with no air to the nozzles.  There may be some = evidence of wear patterns indicating that the tip seal travels some = distance=20 (maybe 4-5=94) from the point of injection before the oil spreads to = the ends of=20 the seals, but I=92m not aware of any direct comparison wear with and = without=20 the air flow.  Maybe some of our racing friends can have some = input on=20 this.

 

Al

 

Certainly, Al,=20 nobody seems to know how much good that top lube does, if=20 any.

 

 

Richard=20 Sohn
N-2071U

 

------=_NextPart_000_0007_01C679AD.3EB5E910--