Received-SPF: pass
 receiver=logan.com; client-ip=128.156.10.12; envelope-from=Joseph.M.Berki@grc.nasa.gov
Message-Id: <5.1.1.5.2.20040907132522.017b39b8@popserve.lerc.nasa.gov>
Date: Tue, 07 Sep 2004 13:26:45 -0400
To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>
From: Joseph M Berki <Joseph.M.Berki@grc.nasa.gov>
Subject: Re: [FlyRotary] Photos of Core tanks internals
In-Reply-To: <list-400726@logan.com>
Mime-Version: 1.0
Content-Type: text/plain; charset="us-ascii"; format=flowed

Ed,
         Is the core pictured 3.75" thick? Thanks

Joe Berki
Limo EZ

At 12:38 PM 9/7/2004 -0400, you (Ed Anderson) 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 -----
>From: "David Carter" <dcarter@datarecall.net>
>To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>
>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 -----
> > From: "Ed Anderson" <eanderson@carolina.rr.com>
> > To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>
> > 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