"The rub for a closed system is that all the energy put into the water eventually turns to heat. This is the result of pressure drops through the remainder of the system."
which is precisely the point being pressed upon me
but (being an experimentalist) why can I not measure such ?
take the case of a high flow resistance wb at a high flow rate
the energy represented by the pressure drop (~3psi @ 3gpm) should, if being converted to heat, be more than sufficient to measure
(isolate and insulate the wb, measure temp diff across inlet and outlet)
any ideas why I see NO change ?
- got me stumped
aahhh . . . .
and having written it out, I believe I 'see' the problem
at 40W input from the die, the coolant temp rise is 0.05°C
if the pressure drop energy is nominally 5W, then I'm trying to measure ~0.0125°C; way too small for my instrumentation and setup to consistently and reliably detect
(but such will, or should, enter into the 'efficiency' determination of the heat die)
quantification indeed !
Ben
well yes, and also no
consider also a positive displacement pump
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