"C/W"s are specific to a particular bench setup,
and will change also for that bench if components or procedures are changed
JoeC and I have worked together for some years, notwithstanding this collaboration I (continue to) have 'issues' with some of his equipment
- specifically his heat dies
consider the SlitEdge results:
Joe's "C/W" is considerably below that from my setup
what are the components of the "C/W" ?
°C, Watts, and the TIM joint
- I will assume that the difference between Joe's and my temps is not so large as our equipment is similar (Fluke 2180A)
- I will again assume that the effect of differences in the TIM joint is not so large
- which leaves the power characterization and the die temp
for Joe to have a lower "C/W", his Watts have to be 'greater' than mine and/or the die temp lower
possible ? - sure, even probable
1. his die has less insulation resulting in greater secondary losses
2. as I understand his setup; while the die pedestal is in contact with the wb, the whole of the heat die body is in close proximity to the wb bp and its top surface uninsulated
- but this should increase the actual heat picked up by the wb
and if so will shift the die temp down a bit
-> but it is also quite possible that where he is reading the die temp may be yielding a lower temp than with my setup ???
none of this will be too clear until Joe has posted 3 or 4 wbs that I also tested
the shame is that Joe is going to put up only the "C/W" at 1gpm
- though I too am mystified by the 'freeflow' and 'waterblock' head loss values
no idea why they should be so different than mine,
but I suspect he has not subtracted the 'connection/pressure tap' losses
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