Thread: Flow Meters?
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Unread 01-13-2003, 10:53 AM   #22
BillA
CoolingWorks Tech Guy
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Join Date: Dec 2000
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no, you are as close as you can get for $100

you can get 0.1°C resolution with the Fluke and TCs described above
-->> but that IS NOT 0.1°C accuracy, a quite different beast indeed

to get 0.1°C accuracy it is held that you need a minimum of a 4-fold greater measurement capability
-> 10-fold is the norm (hence 0.01°C resolution)

I just now received an e-mail from a friend of mine, a (past ?) Sr. Editor of The Journal of Heat Transfer and who does CFD on a 30 tetraflop computer (guess where ?), part of which is copied below:

this is wrt a "Roundup" review of the Atlantis to go up on OCers tomorrow -

"Observation: start putting uncertainty bounds on all data plots. You have it on some, propagate it to all. As a modeler I have to know what is the range of error within the results, i.e. how near to the results do I have to be.

You start putting them there (you would never get published in a serious journal without them) then you can ask others for bounds on their results."

do you see the 'problem' ?
without the definition of uncertainty (what we more casually call accuracy), the numbers are - or may be ?? - junk

one can blithely say "oh, for what we're doing it doesn't matter", and if you believe that then stick with a digidoc and don't sweat reality

zeros are the most expensive digits

google on 'measurement uncertainty'
get 'EAL-22' and 'EAL-R2-S1'
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