yet another cooling variable, perhaps

[<JHertzman@xxxxxxx>]

I am not going to take sides in a thermostatic dispute among friends, but
there is a phenomenon called cavitation- the formation of a partial vacuum in
a liquid by a swiftly moving solid body (as a propellor), also a cavity so
formed - which I understand can affect pump impellers; and which may be
inhibited by resistance on the output side, which increases the pressure at
the point where the cavitation might occur. Many variables there, impeller
design and rotational speed and liquid temperature and godknowswhatelse, but
with the right (or wrong) mix of variables one might have the inpeller
rotating futilly in a bubble without the resistance of a thermostat, but
pumping coolant effectively against the resistance of the thermostat. Or so
the scuttlebut goes. 

And some cooling would still take place due to the thermosiphon-

Not claiming what actually happens, but the heat source, coolant, radiator,
pump, and thermostat are presumably operating as an integrated system, as
designed, and mucking around with one part can sometimes have odd consequences
elsewhere. Or so I have been brainwashed to believe.

John

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