I think you need the rad in there with the pump located at the top
of the the water level to get a meaningful simulation of the
cooling system.

As you can see by Bill's data the pressure drop through the core
is a significant effect as to how much water can be pumped.

BTW it appears from Bill's data that evap cores are unsuited
to centrifugal water pumps. Makes sense as evap cores are used
in air conditioning systems with positive displacement high pressure
piston pumps.

I never ceases to amaze me they don't work worse than they do :-)

Paul Lamar

A/C refrigeration coils (cores as most people say) are just that, coils

of tubing arranged in a serpentine pattern.

Looking at one you can see that the flow is through a single tube from

top, or in some cases from the bottom, but in a radiator the

flow is from a header tank on the end (or top) through all the tubes

simultaneously, (existing, occurring, or done at the same general

time or at the same moment.).
consequently, the flow rate through a radiator is higher by far than

through an evaporator coil.

Pumping type, centrifugal, piston rotary etc, has nothing to do with the

flow rate of the coil.

In the evaporator coil the flow will be through the small tube all the

way through the whole coil, but in the radiator it will flow

through all the tubes at the same time.
Heater coils would be better for flow rate than the evaporator coils,

since most of them have header tanks like a radiator. This is

why water to air heat exchangers us header tanks instead of the

serpentine configuration of the evaporator coils. These are called

cores in the trade, and the evaporators are called coils.
Royce

 Royce, it would be best to study the evaporator cores under discussion
before making these kind of generalizations.
The Harris cores currently in use have ABSOLUTELY NO RESEMBALANCE to your
description of evaporator coils/cores.
Basing design decisions on statements like this is like the junk science
that Paul (and me too) abhores.

Tracy Crook
tcrook@rotaryaviation.com

I don't think anybody is going to use this knowledge in a negative
way Tracy. Lots of oil coolers are built the same way. Several
rotary powered gyros use this type of oil cooler.  It has its
advantages and disadvantages. Burst strength and consequent
reliability is probably one of them. As you imply volume or area
efficiency may be less. The ones used on the gyros are almost
as large as the rad. On the other hand they are located either
in front or behind the rad.

Paul Lamar

Tracy is correct, I had forgotten about the GM evaporators.  Hope this oversight
didn't lead any one astray.
Royce

 
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