Return-Path: Received: from [24.25.9.102] (HELO ms-smtp-03-eri0.southeast.rr.com) by logan.com (CommuniGate Pro SMTP 4.2.1) with ESMTP id 400833 for flyrotary@lancaironline.net; Tue, 07 Sep 2004 13:37:59 -0400 Received-SPF: none receiver=logan.com; client-ip=24.25.9.102; envelope-from=eanderson@carolina.rr.com Received: from EDWARD (cpe-069-132-183-211.carolina.rr.com [69.132.183.211]) by ms-smtp-03-eri0.southeast.rr.com (8.12.10/8.12.7) with SMTP id i87HbTiB026734 for ; Tue, 7 Sep 2004 13:37:30 -0400 (EDT) Message-ID: <000801c49501$5f38cb40$2402a8c0@EDWARD> From: "Ed Anderson" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: Photos of Core tanks internals Date: Tue, 7 Sep 2004 13:37:39 -0400 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0005_01C494DF.D7F03CC0" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2800.1409 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1409 X-Virus-Scanned: Symantec AntiVirus Scan Engine This is a multi-part message in MIME format. ------=_NextPart_000_0005_01C494DF.D7F03CC0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Actually, Mark, there are 5 holes , three toward the center that are = easy to see in the photos and two at the extreme sides of the tanks. = Yes, at first glance, you would think no-way it would cool - heck you = wouldn't even flow much coolant through it. But a 1" dia hose only has = 0.785 inches of area. Surprisingly the total area of these small holes adds up to between = 0.83 and 1.93 sq inches (holes appear to be between 1/8 - 3/16" in dia) = - more than you would think. So certainly a lot of loss with so many = small holes, but if the 1.93 sq inch area is close to their total area = then they are probably as effective at flowing coolant as a 1" hose with = 0.785 sq inches. This is one I successfully flew with before the stress of the heavy = AN-16 fittings hanging off the 90 deg fitting cause it to spring a small = leak. Ed Ed Anderson RV-6A N494BW Rotary Powered Matthews, NC ----- Original Message -----=20 From: Mark Steitle=20 To: Rotary motors in aircraft=20 Sent: Tuesday, September 07, 2004 1:06 PM Subject: [FlyRotary] Re: Photos of Core tanks internals Ed,=20 What is amazing to me is that there are only three small holes in each = cross-tube. Its hard to believe that these small holes will pass enough = coolant to cool a 13B @ WOT. =20 Mark S. At 12:38 PM 9/7/2004 -0400, you wrote: Well, David, I just went down to the shop through the pouring = remnants of Frances and cut open each side tank of a core I had taken from the = junkyard years ago. The photos are attached and speak for themselves - no dividers or = other impediments to coolant flow in the tanks - pretty clean channel from = top to bottom. Each "row" has 5 approx 1/8" (perhaps slightly larger) dia = holes that conduct the water through the core to the opposite side tank. = So 14 rows * 5 * area of 1/8-3/16" dia hole would give a cross flow = channel area of around 0.86 sq inches to 1.93 sq inches - probably toward the = larger figure. So as Bill suggested they may have redesigned the heat exchangers to = take a different approach to recondensing the refrigerant calling for the = divider plate. Given the relatively small cross channels, it is my opinion = that a serpentine cooler is probably offering considerably more resistance = to flow. Some of the radiator shop webpages give an estimate of the increase = in flow resistance of a Serpentine core over the straight through - as best = I recall it was something like 4 times as best I recall. So, its clear that not all GM evaporator cores are created the same = way. This one was from the an late 80s early 90s Cadillac. I looked all = over for some identifying model number but could not find anything. I do = recall it had a yellow sticker with a black C on it when I yanked it. In any case, it looks like we can not simply order just any GM = cooler core. I suspect that when they switched over to the more environmental = friendly refrigerant then there could have been some redesign of the core, = but just speculation on my part. Here's the photos Ed. Ed Anderson RV-6A N494BW Rotary Powered Matthews, NC ----- Original Message -----=20 From: "David Carter" To: "Rotary motors in aircraft" Sent: Tuesday, September 07, 2004 11:55 AM Subject: [FlyRotary] Re: Water pump problem > Thanks, Ed. > > I wonder Steve Brooks's core with a "plate" is different from the > GM/Harrison cores that I have (Chev'y Caprice). > - When I probed my core last night and found no plates in the = end cap > with the larger of the two welded tubes, I DIDN'T check the other = side - > those smaller 1/2" OD tubes turn 90 degrees and run about a foot, = so I never > probed that side. That is the side that has the little "filter" = and/or > "expansion jet" thing sitting about an inch down inside. Perhaps = there's a > plate on that side that matches what has been discussed recently. > > If Steve's core is a typical GM/Harrison core, then I'd like to = understand > more about which end "the plate" is in and tell us more about "the = tube that > was removed". I've not yet cut into any of my cores to mod the = fittings, so > am ignorant of the insides. > > David > > ----- Original Message -----=20 > From: "Ed Anderson" > To: "Rotary motors in aircraft" > Sent: Tuesday, September 07, 2004 6:54 AM > Subject: [FlyRotary] Re: Water pump problem > > > > Hey, David, not to worry. We have all hit the "Send" button on = an e mail > or > > two and later wondered why we did. {:>) > > > > Ed > > > > Ed Anderson > > RV-6A N494BW Rotary Powered > > Matthews, NC > > > > >> Homepage: http://www.flyrotary.com/ > >> Archive: http://lancaironline.net/lists/flyrotary/List.html > >> Homepage: http://www.flyrotary.com/ >> Archive: http://lancaironline.net/lists/flyrotary/List.html ------=_NextPart_000_0005_01C494DF.D7F03CC0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Actually, Mark, there are 5 holes = , three=20 toward the center that are easy to see in the photos and two at the = extreme=20 sides of the tanks. Yes, at first glance, you would think no-way it = would=20 cool - heck you wouldn't even flow much coolant through it.  But a = 1" dia=20 hose only has 0.785 inches of area.
 
 Surprisingly the  total area = of these=20 small holes  adds up to between 0.83 and 1.93 sq inches (holes = appear to be=20 between 1/8 - 3/16" in dia) - more than you would think.  = So=20 certainly a lot of loss with so many small holes, but if the 1.93 sq = inch area=20 is close to their total area then they are probably as effective at = flowing=20 coolant as a 1" hose with 0.785 sq inches.
 
 This is one I successfully flew = with before=20 the stress of the heavy AN-16 fittings hanging off the 90 deg fitting = cause it=20 to spring a small leak.
 
Ed
 
Ed Anderson
RV-6A N494BW Rotary Powered
Matthews, NC
----- Original Message -----
From:=20 Mark=20 Steitle
Sent: Tuesday, September 07, = 2004 1:06=20 PM
Subject: [FlyRotary] Re: Photos = of Core=20 tanks internals

Ed,
What is amazing to me is that = there are=20 only three small holes in each cross-tube.  Its hard to believe = that=20 these small holes will pass enough coolant to cool a 13B @ WOT. =20

Mark S.


At 12:38 PM 9/7/2004 -0400, you wrote:
Well, David,  I = just went=20 down to the shop through the pouring remnants of
Frances and cut = open=20 each side tank of a core I had taken from the junkyard
years=20 ago.

The photos are attached and speak for themselves - no = dividers=20 or other
impediments to coolant flow in the tanks - pretty clean = channel=20 from top to
bottom.  Each "row" has 5 approx 1/8" (perhaps = slightly=20 larger) dia holes
that conduct the water through the core to the = opposite=20 side tank.  So 14
rows * 5 * area of 1/8-3/16" dia hole = would give a=20 cross flow channel area
of around 0.86 sq inches to 1.93 sq = inches -=20 probably toward the larger
figure.

So as Bill suggested = they may=20 have redesigned the heat exchangers to take a
different approach = to=20 recondensing the refrigerant calling for the divider
plate.  = Given=20 the relatively small cross channels, it is my opinion that = a
serpentine=20 cooler is probably offering considerably more resistance to = flow.
Some of=20 the radiator shop webpages give an estimate of the increase in=20 flow
resistance of a Serpentine core over the straight through - = as best=20 I recall
it was something like 4 times as best I = recall.

So, its=20 clear that not all GM evaporator cores are created the same = way.
This one=20 was from the an late 80s early 90s Cadillac.  I looked all over = for
some identifying model number but could not find = anything.  I do=20 recall it
had a yellow sticker with a black C on it when I yanked = it.

In any case, it looks like we can not simply order just = any GM=20 cooler core.
I suspect that when they switched over to the more=20 environmental friendly
refrigerant then  there could have = been some=20 redesign of the core, but just
speculation on my = part.

Here's the=20 photos

Ed.


Ed Anderson
RV-6A N494BW Rotary=20 Powered
Matthews, NC
----- Original Message -----
From: = "David=20 Carter" <dcarter@datarecall.net>
To: "Rotary motors in = aircraft"=20 <flyrotary@lancaironline.net>
Sent: Tuesday, September 07, = 2004=20 11:55 AM
Subject: [FlyRotary] Re: Water pump = problem


>=20 Thanks, Ed.
>
> I wonder Steve Brooks's core with a = "plate" is=20 different from the
> GM/Harrison cores that I have (Chev'y=20 Caprice).
>     - When I probed my core = last night=20 and found no plates in the end cap
> with the larger of the = two welded=20 tubes, I DIDN'T check the other side -
> those smaller 1/2" OD = tubes=20 turn 90 degrees and run about a foot, so I
never
> probed = that=20 side.  That is the side that has the little "filter" = and/or
>=20 "expansion jet" thing sitting about an inch down inside.  = Perhaps=20 there's
a
> plate on that side that matches what has been = discussed=20 recently.
>
> If Steve's core is a typical GM/Harrison = core,=20 then I'd like to understand
> more about which end "the plate" = is in=20 and tell us more about "the tube
that
> was removed".  = I've=20 not yet cut into any of my cores to mod the fittings,
so
> = am=20 ignorant of the insides.
>
> David
>
> ----- = Original Message -----
> From: "Ed Anderson"=20 <eanderson@carolina.rr.com>
> To: "Rotary motors in = aircraft"=20 <flyrotary@lancaironline.net>
> Sent: Tuesday, September = 07,=20 2004 6:54 AM
> Subject: [FlyRotary] Re: Water pump=20 problem
>
>
> > Hey, David, not to worry.  = We have=20 all hit the "Send" button on an e
mail
> or
> > = two and=20 later wondered why we did. {:>)
> >
> > = Ed
>=20 >
> > Ed Anderson
> > RV-6A N494BW Rotary=20 Powered
> > Matthews, NC
>
>
>
>=20 >>  Homepage:  http://www.flyrotary.com/
> = >> =20 Archive:   http://lancaironline.net/lists/flyrotary/List.html=
>



>> =20 Homepage:  http://www.flyrotary.com/
>> =20 Archive:   http://lancaironline.net/lists/flyrotary/List.html=
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