Return-Path: Received: from [65.33.85.197] (account ) by logan.com (CommuniGate Pro WebUser 4.1b1) with HTTP id 2071692 for ; Tue, 18 Mar 2003 21:22:24 -0500 From: "Marvin Kaye" Subject: Re: [FlyRotary] weird cooling ideas, part 2 To: flyrotary X-Mailer: CommuniGate Pro WebUser Interface v.4.1b1 Date: Tue, 18 Mar 2003 21:22:24 -0500 Message-ID: In-Reply-To: <000301c2edb8$e5aed1c0$1702a8c0@WorkGroup> MIME-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1"; format="flowed" Content-Transfer-Encoding: 8bit Posted for "Ed Anderson" : Would be interesting to see how it works, Rusty. I personally do not see how it could possibly work as well as the multiple fins of a radiator. Assuming that the fins in my 9x10x3.25" radiator are 1/16" apart That gives 9/(1/16) or 9/.0625 = 144 fins across its width of 9". For simplicy sake lets assume the fin runs the thickeness of the radiator (3.25") then the square inches of fin area in one row is 144*3.35 = 468 square inches of cooling surface for one row (Ok, the fins don't run all the way through, but doubt if I am off by a whole lot). Assuming the fin rows are approx 3/8" high then with a 10" high radiator we get 10/(3/8) = 10/.375 = 26 rows of finns. With one row = 468 sq inches then x 26 = 12,480 square inches of surface area for cooling in a 9x10x3.25 radiator. Now they claim their finned tube has 5 times the surface area of a non-finned tube. They say its finns form a 1 3/8" diameter space around the tube but the inside is the size to thate a 3/4" pipe threat. So lets say the tube is 1" in diameter (without fins for the moment). Then a 9' section would give the following area: Circumference = pi*D = 3.1415 * 1 = 3.1415" so the 9 foot section would have a surface area of approx 3.1415 x (9x12) = 339.282 square inches. Now the fins are claimed to add a surface area of 5 times that or 339.282 x 5 = 1696.41 square inches of cooling surface (approx) for the 9 foot lenght. so comparing that to the single radiator above 12,480/1696.41 = 7.356 sections 9 feet long or approx 66 feet of this tubing to equal one GM evaporator core. Now my airplane takes two of the evaporator cores, so all things being equal you would need approx 132 feet of that tubing. So unless my math is way off (always possible), Rusty, I would recommend saving your money for something like a custom radiator. FWIW Ed Anderson >>> I'm still thinking about ways to make a low frontal area radiator, and in looking at custom radiators, oil coolers, etc, I ran across this "Cool Tube" stuff: http://www.alumrad.com/howecoolers.htm<<<