Return-Path: Received: from [24.25.9.102] (HELO ms-smtp-03-eri0.southeast.rr.com) by logan.com (CommuniGate Pro SMTP 4.1.8) with ESMTP id 2952324 for flyrotary@lancaironline.net; Tue, 27 Jan 2004 22:34:32 -0500 Received: from edward (clt78-020.carolina.rr.com [24.93.78.20]) by ms-smtp-03-eri0.southeast.rr.com (8.12.10/8.12.7) with SMTP id i0S3YTVS001731 for ; Tue, 27 Jan 2004 22:34:30 -0500 (EST) Message-ID: <002a01c3e54f$a88fcf80$2402a8c0@edward> From: "Ed Anderson" To: "Rotary motors in aircraft" Subject: Truncating Streamline Ducts Date: Tue, 27 Jan 2004 22:34:38 -0500 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0027_01C3E525.BF450CB0" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2800.1158 X-MIMEOLE: Produced By Microsoft MimeOLE V6.00.2800.1165 X-Virus-Scanned: Symantec AntiVirus Scan Engine This is a multi-part message in MIME format. ------=_NextPart_000_0027_01C3E525.BF450CB0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable I mentioned the recent article in Sport Aviation on Liquid cooling in a = previous post. I then located one of the authors and ask a couple of = questions. One of the question I asked the author his opinion as to the = effectiveness of truncating the Streamline duct coordinates (since even = it gets a bit long for an aircraft installations). The author Neal Willford responsed as follows: 3) I am well aware of the painful reality of trying to do an 'optimum' = installation. Yes, you should be able to truncate the Kuchemann = bellmouth style diffuser. Most of the diffuser is fairly shallow slope = before it bellmouths up to the cooler. It's the bellmouth shape that = matters the most. You might try laying out the ideal one and truncating = it off at the max length you can do and try that (or is that what you = have already done?). =20 I hope this helps. Please keep me posted if you do any more = experimenting! Regards, Neal Neal's suggested approach is the approach I took when I modified one of = my cooling ducts and as I reported it seemed to make a big difference = even though I had to truncate the Streamline coordinates quite a bit. I = simple kept the bellmouth end (the end next to the radiator) and = truncated out toward the inlet. My duct has an effective lenght of = probably around 6". Yet, it still seems to help considerably over the = old duct. FWIW Ed Anderson RV-6A N494BW Rotary Powered Matthews, NC ------=_NextPart_000_0027_01C3E525.BF450CB0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable

I mentioned the recent article in Sport = Aviation on=20 Liquid cooling in a previous post. I then located one of the = authors and=20 ask a couple of questions. One of the question I asked the = author his=20 opinion as to the effectiveness of truncating the Streamline duct = coordinates=20 (since even it gets a bit long for an aircraft = installations).

The author Neal Willford = responsed as=20 follows:

3) I=20 am well aware of the painful reality of trying to do an 'optimum'=20 installation. Yes, you should be able to truncate the Kuchemann = bellmouth=20 style diffuser. Most of the diffuser is fairly shallow slope = before it=20 bellmouths up to the cooler. It's the bellmouth shape that matters = the=20 most. You might try laying out the ideal one and truncating it off = at the=20 max length you can do and try that (or is that what you have already=20 done?).

I hope=20 this helps. Please keep me posted if you do any more=20 experimenting!

Regards,

Neal

Neal's = suggested=20 approach is the approach I took when I modified one of my cooling = ducts and=20 as I reported it seemed to make a big difference even though I had to = truncate=20 the Streamline coordinates quite a bit. I simple kept the = bellmouth end=20 (the end next to the radiator) and truncated out toward the inlet. = My duct=20 has an effective lenght of probably around 6". Yet, it still seems to = help=20 considerably over the old duct.

FWIW

Ed Anderson
RV-6A N494BW Rotary=20 Powered
Matthews, NC

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