> > This is what I would call an "invented rationalization".
> > There is no way that more coolant flow will give less cooling.
> > It is a thermodynamic impossibility. Much more likely is that
> Isn't it possible that the coolant could leave the radiator before much
> of the heat it contained was transfered to the air flowing through the
> radiator?
No, it isn't possible. The coolant inside the radiator is in constant
thermal contact with the inside of the radiator metal. What difference
does it make whether one coolant particle at 100C or ten coolant particles
at 100C are in contact with a piece of metal at 100C during a time span?
The answer, of course, is "none", but if the metal is at 99C, then you
will get a fair bit more heat transfer from the coolant to the metal if
more coolant is exposed to the metal per unit time.
> Since air doesn't absorb heat very well, it seems possible
> that this could happen.
That's because you aren't regarding the coolant as a closed system.
The metal-to-air heat transfer removes heat from the metal. The metal
removes exactly the same amount of heat from the coolant - regardless
of the flow rate of coolant. These rates of heat removal must match,
or the state will change.
Of course, the above assertions are in regards to steady state operation.
During warmup, or while changing from one coolant flow rate to another,
you will see some dynamical effects, but they still add up to more flow
implies more heat transfer (or at worst the same heat transfer).
> How long does it take a quanta of water to move
> through a radiator?
This is a good question only if it is regarded in a systemic manner -
how long does it take a quantum of coolant to move through the engine?
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John R. Lupien
lupienj@wal.hp.com
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