X-Mozilla-Keys:                                                                                 

Rodger Hilyard wrote:

FYI....................

http://www.usradiator.com/options.htm

U.S. Radiator Corporation

       SNIP

 (More snip)

Bill Freeman wrote:

It appears that this is the counterflow design, in production.  If
I read this correctly, the hot water goes in the rear, then thru the

middle

then thru the front, working like a correct counterflow heat

exchanger

design.  This is a medium big deal.

Alfonso Lebron wrote:

Seems to me that there is NO counterflow in this system. In order to
have it, the water flow direction should be going opposite the air
flow direction. This is necessary to take advantage of the multyplying
effect on the heat transfer along and across the interface between
both fluids.

Alfonso Lebron-Berges

Yes! These rads are not counterflow. Counter flow does indeed work
with thick rads because many people have reported a reduction in 
heat transfer efficiency with additional rad thickness.

Corky Bell, Maximum Boost; 
"The first half of the rad does 3/4 of the work."

Heinz Heisler, Advanced Engine Technology;
"Increasing the matrix core depth increases the
heat dissipation capacity but this capAcitv increase 
becomes much smaller beyond some criticAl depth. For 
example a 50% increase in core depth improves the 
heat dissipation capacity by 15% whereas a 100% 
increase in depth raises its cApacity by only 20%"

To my knowledge the principle was first applied to air cooled engines
by Franklin in the early thirties. Several radial aircraft engines
used the principle by placing the cool intake valve ahead of the
hot exhaust valve. Herschel Smith, A History of Aircraft Piston 
Engines.  

There would be no benefit with a one row rad.
The fact that the air changes temperature as it passes through
a thick rad is evidence there can be a benefit to counter flow.

Heinz Heisler, Advanced Engine Technology again;
"The thermal capacity of the radiator is increased 
by something like 1.8% for each 1 deg C increase of 
temperature difference between the coolant input 
temperature and the input air temperature." 

It pays to keep the average temperature as high as possible
and this can be cheaply done in any rad with more than one row of 
tubes.

Ford rads that use built in water oil heat exchangers use
the counter flow principle.

Come to think of it in Keith Moore's oil pan drawings the water tubes
should run fore and aft with counter flow oil and water.

Paul Lamar
 
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