Return-Path: Received: from ms-smtp-03.southeast.rr.com ([24.93.67.84] verified) by logan.com (CommuniGate Pro SMTP 4.1.5) with ESMTP id 2624298 for flyrotary@lancaironline.net; Sat, 04 Oct 2003 19:39:51 -0400 Received: from o7y6b5 (clt78-020.carolina.rr.com [24.93.78.20]) by ms-smtp-03.southeast.rr.com (8.12.10/8.12.2) with SMTP id h94NbWW0029613 for ; Sat, 4 Oct 2003 19:37:33 -0400 (EDT) Message-ID: <000801c38ad0$86fd8c60$1702a8c0@WorkGroup> From: "Ed Anderson" To: "flyrotary" Subject: Thick Vs Thin Radiators - NASCAR Date: Sat, 4 Oct 2003 19:37:51 -0400 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0005_01C38AAE.FFA127C0" 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 This is a multi-part message in MIME format. ------=_NextPart_000_0005_01C38AAE.FFA127C0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable This is extracted from an article on NASCAR Cooling Radiators. Notice = that they even talk about radiators 7" THICK! The standard apparently = being 3 1/2" thick. Now I am no NASCAR expert, but I know they spend = BIG $$ on getting the ultimate performance out of every component of the = race car. Now the GM evaporator core is probably not anywhere close to = being as effective as one of the NASCAR radiators since its design for a = refrigerant gas rather than water, but it is interesting that they = measure around 3 3/8- 3 1/2" thick. Here is the extract: "Race radiators are all aluminum and range anywhere from 3-1/2 = inches thick to 7 inches thick in the core, with the standard intermediate track radiator being = 3-1/2 inches thick The speedway radiator is usually thicker,said Joey Cogdell of Griffin = Thermal Products. The high speeds force air through them, whereas the = short track radiator needs to be thinner to get the maximum amount of = air-flow" (Eds Note: This implies that the slower the air flow through = the radiator (less dynamic pressure) then the thinner your radiator = needs to be for good cooling - but, if you have the high dynamic = pressure, then a more compact thicker radiator is perhaps a better = solution) Here is the URL if you want to read the entire article http://www.narsa.org/acj/archive/acj200010_tech%20serve.pdf Now if 7" is not too thick for racers traveling in the vicinity of 200 = MPH on the straight away, then 3 1/2" should be just about right many of = us flier. Now if your machine only flies at a speed of 80 MPH then logically you = need to consider thinner radiators. The key appears to be the dynamic = pressure available to produce the Mass flow through the radiator. So = presumably if you fly a P-51 you can fly with 7" or thicker radiators. = Like in most cases, there is the theoretical perfect situation and then = the real world situation. The real world solutions almost always = involved trade-offs and compromises - not perfect - but workable = solutions. So those of you who may have had concerns about radiator thickness here = is some additional data. All the engine cares about is some mechanism = to remove the waste heat - hell, a water hose running through the block = might work, but would require an awfully long hose {:>) FWIW Ed =20 Ed Anderson RV-6A N494BW Rotary Powered Matthews, NC eanderson@carolina.rr.com ------=_NextPart_000_0005_01C38AAE.FFA127C0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable

This is extracted from an article on = NASCAR Cooling=20 Radiators. Notice that they even talk about radiators 7"=20 THICK! The standard apparently being 3 1/2" thick. Now = I am no=20 NASCAR expert, but I know they spend BIG $$ on getting the = ultimate=20 performance out of every component of the race car. Now the GM = evaporator=20 core is probably not anywhere close to being as effective as one of = the=20 NASCAR radiators since its design for a refrigerant gas rather than = water, but=20 it is interesting that they measure around 3 3/8- 3 1/2" = thick.

Here is the extract:

"Race radiators are all = aluminum and range anywhere from 3-1/2 inches = thick=20 to 7 inches
thick in the core, with the standard = intermediate=20 track radiator being 3-1/2 inches thick

The speedway = radiator =20 is usually thicker,said Joey Cogdell of Griffin Thermal = Products. =20 The high speeds force air through them, whereas the short track radiator = needs=20 to be thinner to get the maximum amount of air-flow" (Eds Note: This implies that the slower the air flow = through the=20 radiator (less dynamic pressure) then the thinner your radiator needs to = be for=20 good cooling - but, if you have the high dynamic pressure, then a more = compact=20 thicker radiator is perhaps a better = solution)

Here is the URL if you want to read the = entire=20 article

http= ://www.narsa.org/acj/archive/acj200010_tech%20serve.pdf

Now if 7" is not too thick = for racers=20 traveling in the vicinity of 200 MPH on the straight away, then 3 = 1/2"=20 should be just about right many of us flier.

Now if your machine = only flies at a speed=20 of 80 MPH then logically you need to consider thinner radiators. = The key=20 appears to be the dynamic pressure available to produce the Mass flow = through=20 the radiator. So presumably if you fly a P-51 you can fly with 7" = or=20 thicker radiators. Like in most cases, there is the theoretical = perfect=20 situation and then the real world situation. The real world = solutions=20 almost always involved trade-offs and compromises - not perfect - but = workable=20 solutions.

So those of you who may have had = concerns about=20 radiator thickness here is some additional data. All the engine = cares=20 about is some mechanism to remove the waste heat - hell, a water hose = running=20 through the block might work, but would require an awfully long hose=20 {:>)

FWIW

Ed Anderson
RV-6A N494BW Rotary=20 Powered
Matthews, NC
eanderson@carolina.rr.com

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