[BillA]

"Have I got this right?
In steady state.
An apparent temperature drop is observed across "6in of tube +bits" when coolant inlet is at the same temperature as the Environmental Chamber
This indicates an apparent heat dissipation from coolant to "environmental chamber"
Are we not applying a correction which implies heat absorption by coolant when coolant inlet is at the same temperature as the "Environmental Chamber"?"

yup
and note that the metrology considerations drop out wrt coolant temps
the offset in air temps due to caling in flowing water has me perplexed though (but will impact all calcs equally)
needs resolution re the procedure though

"Tested CoolRad-12T with zero fan and zero temperature differential?"
no, just the crosses; that whole series will be rerun in several hours

bobo will like this,
for 2+ days have been looking for a source of dissipation variation at high flow rates, not understanding that it was the same source as the hysteresis offset
- if the system is started at fulll flow some air is entrained that will not clear until the flow is below 1.5 gpm (using a March M3 pump), a coolant density variation

now that I (think I) have learned how to start the test bench, I wil recal the crosses and do the rad at 0 dT also