Sounds like plenty of core area to me Monty.
Thought I had made my final decision on the oil cooler but still having
trouble getting all my design goals to work with the fluidyne cooler.
Those darn evap cores are hard to beat for weight, performance & size.
I'm back to figuring out a way to make the evap core reliable in oil cooler
service.
Rusty is the resident expert on failures on these things so a couple of
questions for him.
Were the connections on the end tanks welded on? I'm wondering
if the heat may have weakened the furnace brazed joints there since the failures
were always on the ends (I think). I noticed there is an aluminum strap
welded to the end tanks from top to bottom on some Harris cores. Did yours
have this? I am wondering if they are to resist the expansion force trying
to split the tank segments apart.
I have built a test evap core cooler with bonded plates on the
ends tied together with threaded rod. This serves two purposes. It
resists the expansion forces and provides a thicker plate to drill & tap for
AN fittings (no welding required). Even with all the added hardware
it only weighs 5 1/2 lbs. The Fluidyne I was looking at was 12 lbs (and
still would not fit in the space available). Weight is so important to me
that I place a value of $100 per pound on weight savings. For example, the
12 pounds I saved with aluminum landing gear cost an extra
$1200.00.
This may turn out to be a total waste of time in which case I will need a
custom cooler. Ed K., what is the maximum core thickness that you can get
for oil coolers?
Tracy
----- Original Message -----
Sent: Sunday, December 18, 2005 5:47
PM
Subject: [FlyRotary] Heat
Exchangers
I read through all the archives on evaporator
cores and radiators.
I have a few questions for Ed in particular and
anybody else who has any answers or recommendations.
I am going to use radiators mounted in the wing
behind the spar like a ME109. There will be variable inlets and
exits.
I have a Ford evaporator core that is 4 inches
thick. The actual core minus the tanks is 8X9 in. So the core volume is 288
in^3. I will use two of these in each wing.
The reason I am interested in this core is I can
use two Fluidyne or Earl's coolers stacked back to back to form a 4 in
thick oil cooler that is the exact same core size as the evap core. There
would be two oil coolers that measure 4X9 in by 4in
thick. The hot oil is plumbed into the rear 2in cooler and then goes into
the front 2in cooler.
The evap core and the stacked oil coolers
form a nice cooling block that is 12X12.25X4. All of
the plumbing points in the right direction. This is a fast airplane and
will cruise in the 250 mph range, I am not opposed to putting spray bars in
front of the coolers for the occasional very hot day climb. The
coolers are aligned with the outer portion of the prop arc under the wing so
they will be in a fairly high velocity air stream on the ground.
Do you guys think that this
will be adequate cooling for a Pport 13b?
Any big problems with the
Ford Evaporator cores VS GM? They look to be the same except for the
thickness and dimensions just happen to coincide with the oil
coolers.
Here are the evap cores 2
req:
Here are the oil coolers DB-30110 4
required:
Monty