Return-Path: Received: from [24.25.9.102] (HELO ms-smtp-03-eri0.southeast.rr.com) by logan.com (CommuniGate Pro SMTP 4.1.5) with ESMTP id 2649651 for flyrotary@lancaironline.net; Fri, 24 Oct 2003 13:48:51 -0400 Received: from ms-mss-03-ce0-1 ([10.10.1.39]) by ms-smtp-03-eri0.southeast.rr.com (8.12.10/8.12.7) with ESMTP id h9OHmmhf012082 for ; Fri, 24 Oct 2003 13:48:49 -0400 (EDT) Received: from southeast.rr.com (localhost [127.0.0.1]) by ms-mss-03.southeast.rr.com (iPlanet Messaging Server 5.2 HotFix 1.12 (built Feb 13 2003)) with ESMTP id <0HN9005DLW5CS1@ms-mss-03.southeast.rr.com> for flyrotary@lancaironline.net; Fri, 24 Oct 2003 13:48:48 -0400 (EDT) Received: from [10.10.1.23] by ms-mss-03.southeast.rr.com (mshttpd); Fri, 24 Oct 2003 13:48:48 -0400 Date: Fri, 24 Oct 2003 13:48:48 -0400 From: echristley@nc.rr.com Subject: Re: [FlyRotary] Re: radiator tube sizing To: Rotary motors in aircraft Reply-to: echristley@nc.rr.com Message-id: <5a706c5a517d.5a517d5a706c@southeast.rr.com> MIME-version: 1.0 X-Mailer: iPlanet Messenger Express 5.2 HotFix 1.12 (built Feb 13 2003) Content-type: text/plain; charset=us-ascii Content-language: en Content-transfer-encoding: 7BIT Content-disposition: inline X-Accept-Language: en Priority: normal X-Virus-Scanned: Symantec AntiVirus Scan Engine ----- Original Message ----- From: Al Gietzen Date: Friday, October 24, 2003 12:46 pm Subject: [FlyRotary] Re: radiator tube sizing > Maybe better check your flow rate units; gpm vs cfm. 20 cfm is > way too > high. For a 2-rotor you'd probably need a max of around 25 gpm, which > is about 3.5 cfm. In the immortal words of Homer Simpson: DOH!! Here is revised data using an absolute minimum flow rate of 20'g'pm. 25 should probably be a design minimum, but I from what I've read, 20 can handle the load except in the most extreme conditions. 14ft 6ft 2ft dia wt psi wt psi wt psi .5 4.76 46 2.04 19.7 .68 6.57 .625 7.44 15 3.19 6.46 1.06 2.15 .75 10.71 6 4.59 2.6 1.53 .87 .875 14.58 2.8 6.25 1.2 2.08 .4 1 19.04 1.44 8.16 .62 2.72 .21 1.125 24.1 .8 10.33 .34 3.44 .11 1.25 29.75 .47 12.75 .2 4.25 .07 This data makes my proposed radiator placement a little more feasible. Using a 7/8" tube I'd get less than 3psi backpressure and add 15lbs of water. Using the EWP will save me about 8 of those, so I'm looking at adding about 7lbs and eliminating seperate intakes for cooling.