X-Mozilla-Keys:                                                                                 
Wschertz@aol.com wrote:

--much snips

Russell Kent wrote:
I assume (perhaps incorrectly :-) that US Radiator wouldn't offer
the "triple flow" for the hell of it, and so it must actually
give lower coolant exit temperatures (greater entry/exit delta
Temp) than a conventional radiator would in their automotive
applications.  Why would that be so?
Russell

Paul Wrote
As Fred mentioned it is a question of too much flow. If all tubes
were in parallel like they are in stock rads the water would get
through the rad too fast and not give up enough heat. Don't
forget the car manufactures do a very good job of optimizing
the coolant system for climbing 7% hills at legal highway  speeds
which may not be the same amount of HP and speed used in racing
cars and certainly not the HP and speed required in an airplane.

One other effect not mentioned in the above is the reduction in the heat
transfer resistance on the liquid side. With the US Radiator "folded" into
1/3 design, the flow through the tubes is at a higher velocity, which
improves the heat transfer coefficient. This is likely to be a minor effect
since the air side resistance is greater.

The other effect is that having them is series increases the pressure drop,
and if the water pump can't handle it, the flow will be reduced in volume.
The result will be that the outlet temperature DROPS, and one might think
that you have improved things, but you may be removing LESS heat from the
engine. Without more information, one cannot tell.

Bill

 
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