X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from imo-d20.mx.aol.com ([205.188.139.136] verified) by logan.com (CommuniGate Pro SMTP 5.0.9) with ESMTP id 1094384 for flyrotary@lancaironline.net; Sat, 06 May 2006 08:23:55 -0400 Received-SPF: pass receiver=logan.com; client-ip=205.188.139.136; envelope-from=Lehanover@aol.com Received: from Lehanover@aol.com by imo-d20.mx.aol.com (mail_out_v38_r7.5.) id q.62.68871277 (63000) for ; Sat, 6 May 2006 08:23:04 -0400 (EDT) From: Lehanover@aol.com Message-ID: <62.68871277.318def28@aol.com> Date: Sat, 6 May 2006 08:23:04 EDT Subject: Re: [FlyRotary] Re: oil cooler lines To: flyrotary@lancaironline.net MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="-----------------------------1146918184" X-Mailer: 9.0 Security Edition for Windows sub 5301 X-Spam-Flag: NO -------------------------------1146918184 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit In a message dated 5/5/2006 11:35:47 P.M. Eastern Daylight Time, keltro@att.net writes: One other comment........There is some difference of opinion among the group whether connecting coolers (oil or coolant) in series (as you propose) or in parallel is the most efficient method.........We have group members currently flying with both methods. The series method is just a bigger (single) cooler (in effect). The big difference is that flow velocity through each cooler will be twice as fast through the series coolers than the parallel coolers. Note the turbulence generating dents in the tubes of the cooler. Cooled oil tends to stay in contact with the metal and insulate oil closer to the center of the tube. So, the turbulence generating dents. The lower velocity of the parallel hookup would seem less effective at scouring chilled oil from the tubes. Plus, you know for sure that the exact same mount of oil is going through each cooler. Lynn E. Hanover -------------------------------1146918184 Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable
In a message dated 5/5/2006 11:35:47 P.M. Eastern Daylight Time,=20 keltro@att.net writes:
<= FONT=20 style=3D"BACKGROUND-COLOR: transparent" face=3DArial color=3D#000000 size= =3D2>
One other comment........There is some difference of opinion among th= e=20 group
whether connecting coolers (oil or coolant) in series (as you=20 propose) or in
parallel is the most efficient method.........We have group members=20 currently
flying with both methods.
 
The series method is just a bigger (single) cooler (in effect).
 
The big difference is that flow velocity through each cooler will be tw= ice=20 as fast through the series coolers than the parallel coolers. Note the=20 turbulence generating dents in the tubes of the cooler. Cooled oil tends to=20= stay=20 in contact with the metal and insulate oil closer to the center of the tube.= So,=20 the turbulence generating dents. The lower velocity of the parallel hoo= kup=20 would seem less effective at scouring chilled oil from the tubes.
 
Plus, you know for sure that the exact same mount of oil is going throu= gh=20 each cooler.
 
Lynn E. Hanover
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