X-Virus-Scanned: clean according to Sophos on Logan.com X-PolluStop-Diagnostic: (direct reply)\eX-PolluStop-Score: 0.00\eX-PolluStop: Scanned with Niversoft PolluStop 2.1 RC1, http://www.niversoft.com/pollustop Return-Path: Received: from [24.25.9.101] (HELO ms-smtp-02-eri0.southeast.rr.com) by logan.com (CommuniGate Pro SMTP 4.3c4) with ESMTP id 860482 for flyrotary@lancaironline.net; Thu, 07 Apr 2005 12:17:12 -0400 Received-SPF: pass receiver=logan.com; client-ip=24.25.9.101; envelope-from=eanderson@carolina.rr.com Received: from edward2 (cpe-024-074-185-127.carolina.res.rr.com [24.74.185.127]) by ms-smtp-02-eri0.southeast.rr.com (8.12.10/8.12.7) with SMTP id j37GGN0W023037 for ; Thu, 7 Apr 2005 12:16:24 -0400 (EDT) Message-ID: <002f01c53b8d$29476720$2402a8c0@edward2> From: "Ed Anderson" To: "Rotary motors in aircraft" References: Subject: Cooling Chart Was [FlyRotary] Re: rule of thumb and RV-3 sizes- was Cooling Inlet Areas/Bernie's RV9 Date: Thu, 7 Apr 2005 12:16:31 -0400 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_002C_01C53B6B.A203BAA0" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2800.1106 X-MIMEOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 X-Virus-Scanned: Symantec AntiVirus Scan Engine This is a multi-part message in MIME format. ------=_NextPart_000_002C_01C53B6B.A203BAA0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Jerry; Like most things; it's a tradeoff. Generally more cooling air flow = equals more drag. Somewhere in there one would hope there is an = optimum; but everyone's criteria for trading configuration needs for = drag reduction is different. The attached chart shows radiator cooling = drag as a function of area (actually height for a given width, but same = idea) for a fixed amount of heat rejection. Larger area gives less = drag, and vice-versa. Sorry, best quality I could achieve scanning a scan, and keeping a = manageable file size. Al Al, Interesting chart. =20 Not certain I am interpreting it correctly, though. Not certain what = the X axis is related to is this the height you mention? It appears to show that the thicker radiators produce less drag = overall than the thinner radiator. Is this for equivalent core volume = or core area? Its my understanding that for the same cooling core volume = the smaller surface face core will produce the less drag, is this what = that is showing or the opposite? Sorry to be slow today, I'll blame it = on leaning over my Aerostars engine bay for 7 hours yesterday replacing = a water pump - aches and a restless nights sleep.{:>{ By the way, I order some of those B9EQV spark plugs you mentioned to = see if they reduce the SAG interval compared to the stock plugs. Ed A. -------------------------------------------------------------------------= ----- >> Homepage: http://www.flyrotary.com/ >> Archive: http://lancaironline.net/lists/flyrotary/List.html ------=_NextPart_000_002C_01C53B6B.A203BAA0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
  Jerry;

Like=20 most things; it=92s a tradeoff.  Generally more cooling air flow = equals=20 more drag.  Somewhere in there one would hope there is an = optimum; but=20 everyone=92s criteria for trading configuration needs for drag = reduction is=20 different.  The attached chart shows radiator cooling drag as a = function=20 of area (actually height for a given width, but same idea) for a fixed = amount=20 of heat rejection.  Larger area gives less drag, and=20 vice-versa.

Sorry,=20 best quality I could achieve scanning a scan, and keeping a manageable = file=20 size.

Al

 Al,=20 Interesting chart. 

Not certain I am = interpreting=20 it correctly, though.  Not certain what the X = axis is=20 related to is this the height you mention?

It=20 appears to show that the thicker radiators produce less drag overall = than the=20 thinner radiator.  Is this for equivalent core volume or core = area? Its=20 my understanding that for the same cooling core volume the smaller = surface=20 face core will produce the less drag, is this what that is showing or = the=20 opposite?  Sorry to be slow today, I'll blame it on leaning over = my=20 Aerostars engine bay for 7 hours yesterday replacing a water pump - = aches and=20 a restless nights sleep.{:>{

By the=20 way, I order some of those B9EQV spark plugs you mentioned to  = see if=20 they reduce the SAG interval compared to the stock plugs.

Ed=20 A.

>>  Homepage: =20 http://www.flyrotary.com/
>>  Archive:  =20 = http://lancaironline.net/lists/flyrotary/List.html
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