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LabVIEW projects - RTD Pressure Measurements
Pressure measurements on Residence Time Distribution equipmentDana Christensen (ChemE)
The goal of the program is to execute an automated series of pressure measurements on the Residence Time Distribution - RTD - setup of Dana Christensen (ChemE, The Netherlands).
Dana operates a setup where the normal procedure is to switch valves so a tracer gas can enter a fluidized bed and where gas analysis is used to establish the residence time distribution.
The vi presented in this publication loads a recipe and allows the user to adapt and use the recipe.
Once the vi is started it will present a table where values can be entered for each consecutive step. The table can be pre-loaded with the table that was used the last time.
The front panel of this vi is based on three screens: Settings, Recipe, Main.
The 'Settings' screen displays some system variables and allows the users to set the following settings:
The 'Recipe' screen has a spreadsheet like table. This is the screen that the vi starts with. The spreadsheet can be altered as long as the 'EXECUTE' button remains untouched. Once you hit the 'EXECUTE' button the 'Main' screen will be displayed and the recipe will be executed.
The 'Main' screen displays:
The LabVIEW diagram consists of two sequences: one to execute the recipe and one to abort normal operation.
Sequence 1 - 'Main Sequence' (Frames 0..10)
Frame 0: Initialization 1
Frame 1: Initialization 2
Frame 2: Initialization 3
Frame 3: Initialization 4
Frame 4: Preparations 1
Frame 5: Preparations 2
Frame 6: Preparations 3
Frame 7: Main loop
Frame 8: Termination 1
Frame 9: Termination 2
Frame 10: Termination 3
Sequence 2 - 'Stop Sequence' (Frames 0..2)
Frame 0: Main loop
Frame 1: Termination 1
Frame 2: Termination 2
The close observer will notice that the main loop from the 'Main Sequence' could interfere with the 'Stop Sequence', e.g. if the 'Stop Sequence' sets an analog output to zero the 'Main Sequence' could set in to the next value.
All the included vis have been made with LabVIEW 6.1.
At the time the department of chemical technology of the Delft University of Technology ChemE was named DelftChemTech.
Bart Boshuizen, 2005/09/24