ok, one last time (I promise myself)
the dP in the wb is but one of a number through the WCing system
but does it in particular offer any unique insight into:
1) a wb's performance, or
2) a (unique) means of differentiating between wbs
wrt #1:
as a rule, I find a measurement always preferable to a calculated derivative value, for all the obvious reasons
- a pressure drop can be the difference between 2 measurements, or a single measurement with a differential pressure transducer (which is how I do it)
Since87, I know you do not wish to accept that this topic was extensively discussed in the thread I linked to above - but if you review it you will see that Tecumseh plotted the sqrt of the data and non-linearity was apparent at both 'ends' of the individual data sets
- this is indicative of an experimental error, which was also discussed at length and the error sources fairly well understood
-> the upshot is that the very low flow rates (specifically) have a significantly higher 'uncertainty' due to both the magnetic flow meter's performance at low stream velocities and the rounding errors because I was indicating only to 0.01psi (!)
so YOU need to be very prudent in any conclusions based on the 'tail end' data points
(this is all in that thread, nothing new being stated here)
so does the product of the pressure drop and the flow rate indicate something ?
sure, etc. etc.
wrt #2:
is that something unique ?
in an absolute sense; certainly
is it significant ? (significantly better/more informative than only the dP ?); to me no
the additional complexity is quite beyond all but the engineers
Since87, your degree is showing - which is quite ok,
but not all can follow even my simplistic presentations (having not Dave's skill)
- and I would ask you this ? (which to me is quite obvious, but then I'm rather involved in this)
is not the difference in flow 'configurations' kinda obvious ?
hence also their individual responses to changes in the flow rate ?
well, perhaps not to others (but it sure is clear to me !)
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