here you go LHG, understand that I'm curve fitting with Excel - do not read more into it than that
(sure the end sum has it all together, and different tests can characterize some aspects better than others)
bobo, forgot to attach the photo
Les
Series 4 and 5 are the same crosses + tubing, but swapped end for end (pressure taps reversed but not sensors)
the nominal ID went from 0.53" to 0.92" but as the RTD is protruding in from the branch the area calc is not worth the time, but for sure the velocity is greatly reduced
anyone care to comment on 'h' wrt the probe ?
this whole exercise is bothersome as I'm sure all this is well understood by those better versed in metrology
i.e. we 'measure' by associating a signal with a source, never mind that the sensor is potted within a sheath all elements of which have their own temp gradients
- so the first adjustment is to cal in the medium to be measured
(I cal in flowing water, does this mean that my air temps are off ?)
- now I find a flow (velocity related ?) temp correction ?
surely all this is known, apparently little different than pressure drop corrections
guess I need that book Les, seems experimentally oriented
in any case, using the Series 4 temp corr eq yields the comparison shown
Last edited by BillA; 11-12-2005 at 12:47 PM.
Reason: correction re taps and sensors
|