Return-Path: Sender: (Marvin Kaye) To: flyrotary Date: Thu, 10 Apr 2003 07:50:05 -0400 Message-ID: X-Original-Return-Path: Received: from [216.52.245.18] (HELO ispwestemail1.aceweb.net) by logan.com (CommuniGate Pro SMTP 4.1b2) with ESMTP id 2112422 for flyrotary@lancaironline.net; Thu, 10 Apr 2003 07:05:41 -0400 Received: from 7n7z201 (unverified [209.206.0.195]) by ispwestemail1.aceweb.net (Vircom SMTPRS 2.0.244) with SMTP id for ; Thu, 10 Apr 2003 04:10:34 -0700 X-Original-Message-ID: <000801c2ff51$40609320$c300ced1@7n7z201> From: "William" X-Original-To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: radiators X-Original-Date: Thu, 10 Apr 2003 06:06:33 -0500 MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4133.2400 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4133.2400 > > Tracy - explain the optimal radiator plumbing. I would think that the hottest > water and the coolest air would cool best, but you indicate the opposite? > kevin ------------------------ I'm not Tracy, but the concept is to have the biggest delta-T at all times between the Water and the Air. So as the air is going through the core it is warming up, and the delta-T is getting smaller. By putting the hottest water in the back radiator, it has the biggest delta-T to the already warmed air. The relatively cooler water entering the front radiator sees the cooler air just entering the radiator. Thus you get the biggest delta-T. This is known as "counterflow" arrangement. With parallel flow, the water is cooling off, and the air is heatingup, therefore the delta-T is decreasing, making the exchanger less effective. If you go this route, it will be CRITICAL that you not allow air to leak out between the two cores, or you will lose effectiveness. Bill schertz