I thought I was starting a thread on head sealing, but it evolved into
one on
cooling. My plans are to install a larger radiator and a higher
pressure cap.
This is going to involve a lot of replumbing and other modifications, so
it may
be a while before I report back on the results
I've studied heat transfer and have pondered the "flows to fast theory"
quite a
bit. I've even written down all the energy balances. The explanation
at the
stewartcomponents link is one of the better ones I've seen. I think
what people
forget is that this is about removing the heat generated by the engine
not about
cooling water. The important point is that we are dealing with a closed
system.
At a given set of operating conditions, the heat generated by the engine
is more
or less constant. The amount of heat removed is proportional to the
change in
temperature times the flow rate, i.e. if you double the flow rate, then
half the
temperature change removes the same amount of heat. If the water is
flowing
too fast to cool down, then its flowing too fast to heat up when it
passes
through the engine. I believe a restriction may be beneficial for a
system
which is starting to boil, because it will put a bit higher pressure on
the
block. The water will tend to remain liquid at the higher pressure in
the block
and then flash downstream from the restriction. This will improve heat
transfer, because steam is a poor heat conductor. However, it seems to
me you'd
be better off using a higher pressure cap.
Larry Young
elliottd wrote:
> Michael - Your explanation is very interesting.
>
> Let's hope that Larry Young who started this thread comes back to explain
> what he did to solve his overheating problem that caused him to have to let
> up with his right foot after 20 minutes of leading the pack in hard
> competitive racing.
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