Return-Path: Received: from [65.54.168.124] (HELO hotmail.com) by logan.com (CommuniGate Pro SMTP 4.2.5) with ESMTP id 484949 for flyrotary@lancaironline.net; Sun, 24 Oct 2004 14:08:03 -0400 Received-SPF: none receiver=logan.com; client-ip=65.54.168.124; envelope-from=lors01@msn.com Received: from mail pickup service by hotmail.com with Microsoft SMTPSVC; Sun, 24 Oct 2004 11:07:00 -0700 Received: from 65.54.98.146 by BAY3-DAV20.phx.gbl with DAV; Sun, 24 Oct 2004 18:06:58 +0000 X-Originating-IP: [65.54.98.146] X-Originating-Email: [lors01@msn.com] X-Sender: lors01@msn.com From: "Tracy Crook" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: oil cooler duct suggestion Date: Sun, 24 Oct 2004 14:04:21 -0400 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_00AC_01C4B9D2.5C1E0B00" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: MSN 9 X-MimeOLE: Produced By MSN MimeOLE V9.10.0006.2205 Seal-Send-Time: Sun, 24 Oct 2004 14:04:21 -0400 Message-ID: X-OriginalArrivalTime: 24 Oct 2004 18:07:00.0456 (UTC) FILETIME=[420D8E80:01C4B9F4] This is a multi-part message in MIME format. ------=_NextPart_000_00AC_01C4B9D2.5C1E0B00 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MessageRusty,=20 My oil cooler "diffuser" is almost identical to yours except mine tapers = to zero distance from core at back end. Extensive wind tunnel tests = (squirting compressed air nozzle at inlet and feeling where air came out = of oil cooler) showed that most of it was at the back end (no big = surprise). Already been some better permanent solutions suggested here = but as a quick fix I put a piece of ridge vent material (very porous = fiber stuff used to vent roofs) at the back end to equalize the flow = through the core. Not a great solution but did show measurable = improvement. Your installation is really looking pretty good in the picture you = posted. Only thing I would suggest is to carefully measure the pressure = drop through the scat duct to throttle body. Possibly even worse than = the pressure drop is the heat the air picks up going through that thing = (at least that's my theory). I was flabbergasted at the improvement I = got when I eliminated the scat. Mine was a bit longer than yours so the = penalty may not be that much in your installation. Worth keeping in = mind though. Tracy (suffering flying withdrawal, runway predicted to be dry enough = for takeoff by fly-in time next weekend) ------=_NextPart_000_00AC_01C4B9D2.5C1E0B00 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Message
Rusty,
My oil cooler "diffuser" is almost identical to yours except mine = tapers to=20 zero distance from core at back end.  Extensive wind tunnel tests=20 (squirting compressed air nozzle at inlet and feeling where air came out = of oil cooler) showed that most of it was at the back end (no big=20 surprise).   Already been some better permanent solutions = suggested=20 here but as a quick fix I put a piece of ridge vent material (very = porous=20 fiber stuff used to vent roofs) at the back end to equalize the = flow=20 through the core.  Not a great solution but did show measurable=20 improvement.
 
Your installation is really looking pretty good in the picture you=20 posted.  Only thing I would suggest is to carefully measure = the=20 pressure drop through the scat duct to throttle body.   = Possibly=20 even worse than the pressure drop is the heat the air picks up going = through=20 that thing (at least that's my theory).  I was flabbergasted at the = improvement I got when I eliminated the scat.  Mine was a bit = longer=20 than yours so the penalty may not be that much in your = installation.  Worth=20 keeping in mind though.
 
Tracy  (suffering flying withdrawal, runway predicted to be = dry enough=20 for takeoff by fly-in time next weekend)
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