I think the deal here is to make the flow within the tubes turbulent, so
that all of the fluid gets to be right next to the wall at some point. This
gets back to the laws about heat transfer being proportional to the
temperature difference across the interface. If the fluid along the sides
of the tubes cools, but the fluid in the center is warmer, then stirring
things up will get this warmer fluid out to the sides of the tube, raising
the temperature across the interface, therefore transferring more heat. How
much of a difference does this make? I'm just guessing, but it must be
measurable ( a couple percent maybe?) or they wouldn't exist. How
"unturbulent" is the flow in a normal radiator tube? Any "ME's" out there?
Stu
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