The US Department of the Interior Bureau of Mines has studied exactly that, see here.
In actual practice, like Larry said, it's not quite as easy as it looks in that report.
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The US Department of the Interior Bureau of Mines has studied exactly that, see here.
In actual practice, like Larry said, it's not quite as easy as it looks in that report.
Thanks, David. Well worth the read!
For others not so inclined, test was for duct discharge, not intake, but test conditions are close approximation to those seen by common shop DC. And I dimly recall from Gas Dynamics that inlet turbulence is higher than outlet (worth consideration?). Article is from 1987 and I wonder how modern electronics - - and Amazon marketplace - - would impact a repeat?
Yes, momentum is definitely in your favor on an outlet. I don't think the issues with this measurement have much to do with the generation of the electronics though. This is a case of the measurement physically changing the characteristics of the system under test, not a very desirable situation.