X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from [24.25.9.101] (HELO ms-smtp-02-eri0.southeast.rr.com) by logan.com (CommuniGate Pro SMTP 5.0.4) with ESMTP id 880299 for flyrotary@lancaironline.net; Tue, 13 Dec 2005 10:20:44 -0500 Received-SPF: pass receiver=logan.com; client-ip=24.25.9.101; envelope-from=eanderson@carolina.rr.com Received: from edward2 (cpe-024-074-025-165.carolina.res.rr.com [24.74.25.165]) by ms-smtp-02-eri0.southeast.rr.com (8.12.10/8.12.7) with SMTP id jBDFJg4p027300 for ; Tue, 13 Dec 2005 10:19:42 -0500 (EST) Message-ID: <001001c5fff8$a61e40e0$2402a8c0@edward2> From: "Ed Anderson" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: oil cooler opening Date: Tue, 13 Dec 2005 10:19:44 -0500 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_000D_01C5FFCE.BCE41FE0" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.2180 X-MIMEOLE: Produced By Microsoft MimeOLE V6.00.2900.2180 X-Virus-Scanned: Symantec AntiVirus Scan Engine This is a multi-part message in MIME format. ------=_NextPart_000_000D_01C5FFCE.BCE41FE0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Yes, John, in the best of all possible worlds a duct exiting the = cooler would undoubtedly help. In fact, I attempted that with my two GM = radiator cores - BUT, by the time I had created the two fiberglass ducts = the constraints on their flow mandated by things like engine, mounts, = exhaust, etc, adversely affected the airflow to such a degree that they = actually hurt the cooling (in my case). If you have plenty of room = and/or a location for your cooler where you could avoid the twists and = turns then it may be worthwhile. I have a nose gear, so no way could I = run a duct straight back from my cooler. Also having a "plugs up" = installation puts my exhaust on the bottom also in the way. =20 In the long run, the oil temps are just fine dumping the exit air under = the cowling. That said - if you can round (2-3" dia) (fiberglass? PVC = pipe?) the bottom edge of your firewall (where the air exists) that = reportedly helps considerably by making it easier for air to exit the = cowl. Ed A=20 ----- Original Message -----=20 From: John Downing=20 To: Rotary motors in aircraft=20 Sent: Tuesday, December 13, 2005 9:54 AM Subject: [FlyRotary] Re: oil cooler opening Ed; Thanks for the numbers. Last night I read the article in kit = planes, Oct 99, by Barnaby Wainfan on duct work and his article entitled = wind tunnel said that you need a duct behind the coolers to offset the = drag of the air in the cowling. Has anyone done any practical = applications on this (for Mazdas), or is the air from the coolant and = oil radiators just dumped into the cowling. My very limited = understanding of this, tells me that drag means more fuel needed. Any = and all comments welcome. JohnD From the farm ----- Original Message -----=20 From: Ed Anderson=20 To: Rotary motors in aircraft=20 Sent: Monday, December 12, 2005 9:20 PM Subject: [FlyRotary] Re: oil cooler opening John, The area of my oil cooler opening is 22-24 sq inches about 10" wide = and 2 1/2" high. I don't have the exact dimension handy, but its = opening is approx 3-4" back of the prop flange. So far its worked fine = for about 5 RVs that I am aware of using this approach. Ed ----- Original Message -----=20 From: John Downing=20 To: Rotary motors in aircraft=20 Sent: Monday, December 12, 2005 5:04 PM Subject: [FlyRotary] oil cooler opening Ed; What is the opening area and the distance behind the prop for = the oil cooler inlet. I'm wondering if the opening needs to be as near = the prop as the inlets for the radiators. Thanks in advance. JohnD = Had to cancel the insurance on the ole Colt today and put comp. on - = snowed in for the winter in northern Michigan. ------=_NextPart_000_000D_01C5FFCE.BCE41FE0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Yes, John,   in the best of all = possible worlds=20 a duct exiting the cooler would undoubtedly help.  In fact, I = attempted=20 that with my two GM radiator cores - BUT, by the time I had created the = two=20 fiberglass ducts the constraints on their flow mandated by things like = engine,=20 mounts, exhaust, etc, adversely affected the airflow to such a degree = that they=20 actually hurt the cooling (in my case).  If you have plenty of room = and/or=20 a location  for your cooler where you could avoid the twists and = turns then=20 it may be worthwhile.  I have a nose gear, so no way could I run a = duct=20 straight back from my cooler.  Also having a "plugs up" = installation puts=20 my exhaust on the bottom also in the way.  
 
In the long run, the oil temps are just fine = dumping the=20 exit air under the cowling.  That said - if you can round (2-3" = dia)=20 (fiberglass? PVC pipe?) the bottom edge of your firewall (where the air = exists)=20   that reportedly helps considerably by making it easier = for air=20 to exit the cowl.
 
Ed A 
----- Original Message -----
From:=20 John=20 Downing
Sent: Tuesday, December 13, = 2005 9:54=20 AM
Subject: [FlyRotary] Re: oil = cooler=20 opening

Ed;  Thanks for the = numbers.  Last=20 night I read the article in kit planes, Oct 99, by Barnaby Wainfan on = duct=20 work and his article entitled wind tunnel said that you need a duct = behind the=20 coolers to offset the drag of the air in the cowling.  Has anyone = done=20 any practical applications on this (for Mazdas), or is the air from = the=20 coolant and oil radiators just dumped into the cowling.  My very = limited=20 understanding of this, tells me that drag means more fuel = needed.  Any=20 and all comments welcome.  JohnD   From the = farm
----- Original Message -----
From:=20 Ed Anderson
To: Rotary motors in = aircraft=20
Sent: Monday, December 12, = 2005 9:20=20 PM
Subject: [FlyRotary] Re: oil = cooler=20 opening

John,
 
The area of my oil cooler opening is 22-24 = sq inches=20 about 10" wide and 2 1/2" high.  I don't have the exact = dimension=20 handy, but its opening is approx 3-4" back of the prop flange.  = So far=20 its worked fine for about 5 RVs that I am aware of using this=20 approach.
 
Ed
 
----- Original Message ----- =
From:=20 John Downing
To: Rotary motors in = aircraft=20
Sent: Monday, December 12, = 2005 5:04=20 PM
Subject: [FlyRotary] oil = cooler=20 opening

Ed;  What is the opening = area and the=20 distance behind the prop for the oil cooler inlet.  I'm = wondering if=20 the opening needs to be as near the prop as the inlets for the=20 radiators.  Thanks in advance. =20 JohnD       Had to cancel the = insurance on=20 the ole Colt today and put comp. on - snowed in for the winter in = northern=20 = Michigan.
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