Monty Roberts wrote:

Anybody had any luck finding pressure drop/aiflow, and heat

exchanger

effectiveness data from any radiator manufacturers (Griffin, etc)? How

about

flow rates for the water and oil? I'll put together a spread sheet so
whoever needs it can punch in numbers and get sizes of inlets and exits

etc

if I could just get my hands on this info.

Monty Roberts
RMI
1795 Berry St.
Fayetteville, AR 72701
tmrbrts@swbell.net

I have not tried it in awhile. No luck then. I think we all should ask

email them

for data. That way they will think there is a demand out there for

this

kind of data.

What we need is mass air flow verses air pressure drop across the core

and

heat transfer in BTU/min or watts verses mass air flow and gallons
of coolant per minute. Also what the coolant pressure drop across the
core as a function of gallons per minute coolant flow. This will be
about three graphs. I am glad you are taking up arms in the crusade
for the holy cooling grail Monty. There is still a lot we don't know.

Paul Lamar

The thing that really drives me nutts is that these calculations are all
really easy if you just have the data on the heat exchangers! Everybody

is

just stumbling around in the dark guessing. Just give me a couple days

in a

good heat transfer lab and this is all cake. You can guess at this with
Nusselt numbers, flow rates etc, BUT; it doesn't have to be that hard.

This

was all figured out during WWII. I have a NACA report that spells it all
out. It even has a work sheet for cryin' out loud. All you need is good

heat

exchanger, and rejected heat data. We have the rejected heat data. I'm

sure

that the radiator manufacturers have this data somewhere, we just have

to

find the right person to talk to.

Monty

Right on Monty. I have searched high and low for data on stock rads.
No luck until we got this Stewart Warner oil cooler stuff.

Paul Lamar

Gents,

What we really need is the phone number to each manufacturer's engineering
department.  One of my guys used to work at a glorified radiator
manufacturer as a design/applications engineer.  He lives & breathes this
stuff.  Tells me he used to spend his days answering customer's phone calls
and figuring out why things didn't work as intended (usually had something
to do with customer error... like trying to cool a fluid to a temperature
lower than the heat sink!).  *Those* are the guys we need to talk to.  Not
the sales/marketing weinies!

When I've had problems in industry, I call up the manufacturer, tell 'em
I've got some of their stuff installed and need technical support from
Engineering.  When I get transferred to a sales guy, I'll play dumb, lay on
some really heavy heat transfer terms ("What is the range of the Nusselt
number for the recommended applications?  I think our air velocity may be
too high").  It only takes one or two more transfers and I'm talking to a
real engineer.  Then you can discuss whatever is really on your mind.
Nobody says you can't bluff either.  What are they going to do?  Charge you
with inquiry under false pretenses??

Tom Kendall

 
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