Yep, inlet/outlets on rads are very,
very restrictive. 7/64x1/2" (0.05 sqin or 1/4" diameter hole
equivalent)) at best. I was aware of it when I JB-welded 5/8" and
3/4" over existing tubes and "just wanted to see how it would
work" and then forgot about it.
Drilling holes in tank end plates I also found a small tube inside
one tank and baffles in both tanks. Now removed.
As for airflow, when I get new elbows welded onto the rads I'll
collect new data. I think the large delta is due to the very slow
coolant flow -- stays in rads way too long (and thus not
circulating through the engine fast enough).
Finn
On 2/27/2021 9:32 PM, Steven W. Boese
SBoese@uwyo.edu wrote:
Finn,
If the "WTeng" sensor
location is somewhere in the engine block and not at the
coolant outlet and the "WTout" sensor is in the coolant
exiting the engine, then the coolant flow rate through the
system may need to be increased by enlarging the radiator
connections.� Typically, it seems that at normal operating
temps, the delta-T across the engine and across the radiators
is about 15 deg F.
It also would appear that
the mass air flow through the radiators may need to be
increased since the air delta T is quite large and the temp of
the air exiting the radiators is close to temp of the coolant
exiting the radiators.� If your OAT were increased to 100 deg
F, you could see "WTout" of ~250 deg F with the setup as it is
now.
The attached plots show
the effect of changing only the air inlet and outlet areas of
my system which has ~0.9" id plumbing to the single
radiator.��
FWIW
Steve Boese
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