The new and improved flow readings, and how to get them into the FlowQuik

One last time into the fray. This it the way I have done it.

Using the sharp edge orifices I first set the FQ to the value of one of the PTS  sharp edge orifice plates ( in this case 200 cfm).  The values for the other plates are then plotted (nominal value vs measured values) in a scatter plot using Excel.  A trend line can then be calculated. In this case a simple linear fit works fine. Again the formula is simple y=ax+b.

The formula for the trend line is then something like this y=0.9786x+ 4.57 ( for example). Luckily the Flow Quik software comes with two adjustments that can be used to tweak the readings : flow percentage adjustment ( to adjust the X term) and a leakage adjustment (for the intercept).

so you deduct 0.9786 from 1 =0.0214 +1 ->  so 1.0214->  to percent adjustment is 102.14 %.

just add 4.57 to the leakage adjustment.

again manifold losses

The fix Audietech send for the leakage adjustment makes it actually work ( always good).

The corrected cfm (CCFM) now will take in to account the correction.

The more mathematically inclined will no doubt notice that the fact that while the measurements regress very nicely it does not really prove anything.. with only three points you could fit a sinus ( or a multitude of other functions) wave  and still get 100% fit. While certainly true , I will not chase this bird. Yes I could buy a few more orifice plates , and yes it would be  a little more accurate (maybe). But you have be be a little practical sometimes.

SO now back to porting.

Oh the new and improved  numbers are a tad lower but deviate a maximum of 1 percent in the lower ranges and 0,3% in the upper ranges.

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