X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from mail.theofficenet.com ([65.166.240.5] verified) by logan.com (CommuniGate Pro SMTP 4.3.5) with SMTP id 1022544 for flyrotary@lancaironline.net; Sun, 26 Jun 2005 20:54:38 -0400 Received-SPF: none receiver=logan.com; client-ip=65.166.240.5; envelope-from=jackoford@theofficenet.com Received: (qmail 28958 invoked from network); 27 Jun 2005 00:53:35 -0000 Received: from dpc691941229.direcpc.com (HELO jack) (69.19.41.229) by mail.theofficenet.com with SMTP; 27 Jun 2005 00:53:35 -0000 Message-ID: <00b201c57ab2$6a585b70$6a01a8c0@jack> From: "Jack Ford" To: "Rotary motors in aircraft" References: Subject: Re: Message with possible fraud attempt: [FlyRotary] Re: Coolant Leak Date: Sun, 26 Jun 2005 17:51:46 -0700 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_00AD_01C57A77.B8C6A450" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2800.1478 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1478 This is a multi-part message in MIME format. ------=_NextPart_000_00AD_01C57A77.B8C6A450 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable ----- Original Message -----=20 From: David Leonard=20 To: Rotary motors in aircraft=20 Sent: Sunday, June 26, 2005 11:39 AM Subject: Message with possible fraud attempt: [FlyRotary] Re: Coolant = Leak On 6/26/05, Al Gietzen wrote:=20 Al, all I can tell you is that the pressure would go immediately = (within 2 seconds) to 21-24 psi. Then as the engine warmed up the = pressure would drop to a nominal 8 psi or so=20 It makes sense to me Ed. Heat the coolant just a little, and it = needs to expand just a little. In order for any of the coolant to flow = out past the cap (even just a little coolant), it must reach the = pressure rating of the cap.=20 How much can the coolant heat up in 2 seconds after start? Just = about zero. The only thing that is heated a little in that time is the = rotor housing walls. Maybe that reduces coolant volume. In any case, if = you have any radiator hose in the system, it will expand enough to keep = the pressure from increasing that much. There is some weird science in = here somewhere.=20 Al Do you mean "just about zero", or absolutely zero? Just about zero would imply something slightly larger than zero. = Which means that the coolant expands something just a little more than = zero. If you truly have no air in the system, an expansion of just = about zero still has to open the pressure cap, which requires opening = pressure. If you sealed water in a steel box with no air, heating the = water a fraction of a degree would raise the pressure hundreds of psi. = Just a few degrees will deform the steel box. Its not weird science, = its just weird freaks of nature. Not even a weird freak of nature, = everything in the engine is related, in terms of stress and pressure = transfer, under Hooke's and Pascal's Laws. The eensiest bit of expansion = of the coolant must displace it's container walls in proportion to the = pressure. If you mean absolutely zero heating of the coolant a few seconds after = starting I will take exception. That flame is well over 2000 deg F and = the rotor housing water jacket is not very thick. Easy to calculate if = we know the BTU quantity per time and the heat tranfer coefficients = (heat conductivity), thicknesses and areas of the materials present. = Some (although small) heating of the coolant easily occurs within one = second after starting the engine. Has to, or it wouldn't occur later, = either. Someone mentioned radiator hose expansion. I don't know about your = system, but my steel braided hose is going to take a lot more than 25 = psi before it allows any expansion. Reread Hooke's Law. Will probably = add to the "springiness" of the whole system). 25 PSI is nothing. Not = going to harm any part of anyone's cooling system except maybe with = multiple cycles. Not likely even with multiple cycles, because the = pressure is an insignificant fraction of the yield strength of any of = the materials we are dealing with. That said, I also believe in having = an air spring/absorber. The main part of my cooling system I keep full, = but have a 1 qt pressurized overflow can that is empty at engine start. = I like that so much I'm going to incorporate it (Shameless copy of an = excellent idea). =20 Jack Ford=20 (The friendly nit-picker). --=20 Dave Leonard Turbo Rotary RV-6 N4VY http://members.aol.com/_ht_a/rotaryroster/index.html http://members.aol.com/vp4skydoc/index.html=20 ------=_NextPart_000_00AD_01C57A77.B8C6A450 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
 
----- Original Message -----
From:=20 David=20 Leonard
Sent: Sunday, June 26, 2005 = 11:39=20 AM
Subject: Message with possible = fraud=20 attempt: [FlyRotary] Re: Coolant Leak






On 6/26/05, Al=20 Gietzen <ALVentures@cox.net>=20 wrote:=20

 Al, all I can = tell you is=20 that the pressure would go immediately (within   2 = seconds) to=20 21-24 psi.  Then as the engine warmed up the pressure would = drop to a=20 nominal 8 psi or so

 

It makes sense to me Ed.  Heat the = coolant just=20 a little, and it needs to expand just a little.  In order for = any of=20 the coolant to flow out past the cap (even just a little coolant), = it must=20 reach the pressure rating of the cap. =

 

How = much can the=20 coolant heat up in 2 seconds after start?  Just about = zero.  The=20 only thing that is heated a little in that time is the rotor housing = walls.=20 Maybe that reduces coolant volume.  In any case, if you have = any=20 radiator hose in the system, it will expand enough to keep the = pressure from=20 increasing that much.  There is some weird science in here = somewhere.=20

 

Al

Do you mean "just about zero", or absolutely zero?
 
Just about zero would imply something slightly larger than=20 zero.  Which means that the coolant expands something just a = little=20 more than zero.  If you truly have no air in the = system, an=20 expansion of just about zero still has to open the pressure cap, = which=20 requires opening pressure.  If you sealed water in a steel box = with no=20 air, heating the water a fraction of a degree would raise the pressure = hundreds of psi.  Just a few degrees will deform the steel = box.  Its=20 not weird science, its just weird freaks of nature. Not=20 even a weird freak of nature, everything in the engine is related, in = terms of=20 stress and pressure transfer, under Hooke's and Pascal's Laws. The = eensiest=20 bit of expansion of the coolant must displace it's container walls in=20 proportion to the pressure.
 
If you mean absolutely zero heating of the coolant a few seconds = after=20 starting I will take exception.  That flame is well over 2000 deg = F and=20 the rotor housing water jacket is not very thick. Easy to=20 calculate if we know the BTU quantity per time and the heat = tranfer=20 coefficients (heat conductivity), thicknesses and areas of the = materials=20 present. Some (although small) heating of the coolant = easily=20 occurs within one second after starting the engine. Has=20 to, or it wouldn't occur later, either.
 
Someone mentioned radiator hose expansion.  I don't know = about your=20 system, but my steel braided hose is going to take a lot more than 25 = psi=20 before it allows any expansion. Reread = Hooke's=20 Law. Will probably add to the=20 "springiness" of the whole system). 25 PSI is = nothing.  Not=20 going to harm any part of anyone's cooling system except = maybe with=20 multiple cycles. Not likely even with = multiple=20 cycles, because the pressure is an insignificant fraction of the yield = strength of any of the materials we are dealing = with.  That=20 said, I also believe in having an air spring/absorber.  The main = part of=20 my cooling system I keep full, but have a 1 qt pressurized overflow = can that=20 is empty at engine start. I like that so much = I'm going to=20 incorporate it (Shameless copy of an excellent idea).  =
 
Jack Ford
(The friendly nit-picker).

--
Dave Leonard
Turbo Rotary RV-6 N4VY
http://memb= ers.aol.com/_ht_a/rotaryroster/index.html
http://members.aol.c= om/vp4skydoc/index.html=20



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