I have followed in detail the discussions--anecdotal, scientific,
intuitive and experiential arguments that show a wide range of input and
a great deal of thought--why not my two cents worth?
The physics is undeniable--and has been well explained. I appreciate
the time it took to get it down and the clarity with which it was
stated. The problem that most of the '..but when I...' examples have
when used to demonstrate the weaknesses of the stated laws of
thermodynamics have when it comes to automotive cooling system design is
that they always seem to deal with more than one variable. Increasing
the engine idle speed to 2000rpm increases the airflow across the
cooling fins of the radiator--as well as the volume of coolant through
the system for heat exchange--as well as the amount of heat being
generated by the engine as more fuel is being combusted. The temp might
go up--or it might go down. The total amout of heat exchange has to be
determined measuring the entire system and I am sure that is beyond the
means of all of us financially.
The strength of the 'pure physics' argument can be understood
intuitively, I believe, if we look at the drive we have to increase the
size of our heat exchange units--radiators and make sure that hoses are
adequately sized and don't collapse. If we could, all of us would like
to see twice the amount of coolant flowing through our motors. If the
radiator surface is inadequately sized--if the airflow is restricted--we
overheat.
If slowing the volume of coolant increased the efficiency of the cooling
system, a thermostat would work in reverse--wide open when cold and
closed when hot--and we know it doesn't work that way. In cold
climates--and Southern California isn't one of them--a thermostat keeps
an engine at operating temperatures during the coldest of times. I
don't use thermostats in anything but the Bricklin--and there I use a
low-temp thermostat.
Cavitation usually occurs if the coolant is contaminated with commercial
'flushes' or additives that are detergent in nature, if the coolant
level is low, or if the pressure cap is defective or improperly sized.
If our cooling systems are well maintained and free of corrosion or
calcification and the coolant is in good shape, the only two options we
have to improve the heat exchange capability of our engines is to
increase the coolant flow--removing restrictions or installing
high-volume water pumps(is there such a thing?)--or improving the
efficiency of the heat exchange process at the radiator with a larger
core and higher air flow.
The marriage of the theoretical and the practical in automotive design
is what the Bricklin is all about. Let the games continue....
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