6. Calculation of a flowmeter with depressurizing element
6.1 Software
Over the last century, numerous experimenters have measured the discharge coefficients C of various orifices. The data were first collected in tables, then smoothed out in the form of empirical relationships that could be processed by desktop numerical calculators, and more recently by microcomputers. These relationships are therefore evolving, and the formulation due to Stolz, used since 1980 for diaphragms, is tending to become obsolete in favor of the Reader/Harris-Gallagher equation, which in certain cases allows the lower limit of the aperture ratio to be significantly lowered.
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Calculation of a flowmeter with depressurizing element
Signal processing and measurement dynamics (rangeability)
Installation
Insert the CD ROM into the drive and double-click on "My Computer".
Double-click on the "Setup" icon.
The installation program generates a Program Files \TI\DepWin directory, but you can choose to create a different directory; an icon is also created, and placed on the "Desktop". If this is not the case, you can create a shortcut from Windows Explorer. Don't forget (if you...
Controls
Program commands can be accessed either from a menu bar or from a toolbar below. The list of commands and how to access them is :
The wording of the toolbar icons is that of the hint message that appears when the cursor is brought close to the corresponding icon.
1. File/New menu or "Reset" icon: variables on screen are completely erased. Use to perform a new calculation without...
Program description
Program
The program includes the following functional elements:
A practical note on checking integrated orifices
This note is intended for users who attempt to verify built-in orifices using the present program.
Integrated orifices are devices whose diameters are generally below the minimum limits set by ISO for pipe and primary element diameters, and which may deviate from the standard in many other respects: it is therefore by no means certain that their coefficients are...
Printing data
The DEPWIN program can print out the results displayed on the screen. To do this, simply activate the "Print" command (§ 2). A second screen appears, showing the results as they will be printed.
At the top of this screen is a toolbar:
the first three buttons from the left are zooms, allowing you to select the data display. They have no further effect...
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