I would like to suspect measurement error, but I'm running out of ideas as to the 'source' of the discrepancy - if any ??
a brief outline of the methodology:
tested in an environmental chamber using RTDs, recirculating chiller, and mag flow meter; all cal'ed as appropriate
rads mounted horizontally w/baffle plate to reduce re-circulation
cycle run from max flow to min, readings at equilibrium
pressure and temps for coolant at insulated crosses at 2" from connections, lines insulated from before cross to DUT
my question: what could be causing a reduction in the temp measured at the rad output ?
- yes, frictional heating is a candidate
but I'm not too sure that there is an error involved, looking at the data there is an apparent shift of the max diss to higher flow with more air flow as well
and note the difference in the decreased diss at max flow, were the airflow increased more the dissipation curve would likely go flat
-> but if there is no error here, then there was an error in the ThermoChill 'setup' - what would cause the higher flow rate data to indicate a 'greater' dissipation
(I re-ran the 120.1 and the apparent dissipation tailed off as with this data
lolito, Les
yes, there are a number of 'energy' considerations - but are they so relevant to the bench testing evaluation of a rad ?
for example the head loss is very much a function of the connector installed, which has no bearing per se on the dissipation characteristics of the rad
- am I missing something ?
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