uk weblab – setup and use - computational modelling group · pdf file ·...
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UK Weblab –Setup and Use
Markus Kraft, Andreas Braumann,Charles Immanuel, Phillip Robbins14 March 2008
CoMo [email protected]
The Weblab project
• Cambridge-MIT Institute (CMI)
• Prof Clark Colton (MIT), Dr Markus Kraft (CU)
• Explore the use of remotely accessible experiments in chemical engineering curriculum
• MIT heat exchanger
• Cambridge reactor
CoMo [email protected]
Cambridge Weblab
• Chemical Reactor
• Industrial Process Control System (PCS7)
• Set up in 2006
• used at differentuniversities
CoMo [email protected]
Equipment• Chemical Reactor
• Ancillary equipment
• SIMATIC S7-400 controller
• Siemens Industrial PCs
CoMo [email protected]
Reactor
• 100 – 300 ml variable volume
• Variable, ideal – non ideal
• Variable stirrer speed
• Temperature controlled
• Three controlled feeds
• Conversion monitored by spectrometer
• Dosing of tracer
CoMo [email protected]
Ancillary Equipment
• Storage tanks
• Siemens Coriolis flow meters
• Peristaltic pumps
CoMo [email protected]
Ancillary Equipment
• Dosing unit
• Heater bath
• Flow cell with fibre optics
• Spectrophotometer
• Webcam
CoMo [email protected]
Computers
• Programmable Logical Controller (PLC) SIMATIC S7-400
• Engineering Station
• Operating System Server
• Web Server
CoMo [email protected]
Stirrer, 0-5V
SITRANS T
OS Server
Web Server(PCS7 Client)
Plant Bus (Industrial Ethernet)
DP Link
DP/PA Coupler
S7 400
PROFIBUS PA
PROFIBUS DP
ET 200M
AI AO DI DO
Analogue and Digital Inputs/Outputs
Peristaltic pumps, 0-4V
DosingHeater bathHot water
circulation
MASSFLOMASS DI 1.5
Engineering Station
Terminal Bus (Industrial Ethernet)
Internet
SPM4-20 mA
PCS7 OS Web Client
Plant wiring scheme
CoMo [email protected]
Non-ideal Reactor Exercise
Ideal and non-ideal reactor
• Reaction constants based on batch data
• RTD tests
• Predict required flow rates for desired conversion under continuous operation
• Experimental session to test predictions
CoMo [email protected]
Users
• University of Cambridge
• MIT
• Imperial College London• University of Birmingham• University of Newcastle
• Loughborough University
Imperial College London
• Enormous educational value in hands‐on laboratory experiments‐ Course: Process Modelling, Dynamics and Control
• Industry standard control software‐ Siemens distributed control system
• Ideal process‐ Challenging yet realistic
Process Dynamics & Control Exercise• Dynamic modelling
- experimental data for validation
• Design of feedback controllers- tuned through experiments, empirical tuning laws, and theoretical considerations
• Design of feedforward controllers
• Experimental testing of the controller effectiveness
- faced with real-life vagaries
Process Dynamics & Control Exercise
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12:23:02 12:25:55 12:28:48 12:31:41 12:34:34 12:37:26 12:40:19
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• Dynamic modelling- experimental data for validation
• Design of feedback controllers- tuned through experiments, empirical tuning laws, and theoretical considerations
• Design of feedforward controllers
• Experimental testing of the controller effectiveness
- faced with real-life vagaries
Manipulated variable
Controlled variable
Process Dynamics & Control Exercise
• Student comments- very enjoyable/ challenging- opportunity to appreciatelimitations of theory
• Lecturer comments- excellent motivational tool- cover much ground through single exercise
Weblab – University of Birmingham
• Who used it?– 2nd Year chemical engineering undergraduates
• Which course?– Forms part of a linked control course, the first half is Process Systems, and the second Principles of Process Control within the Chemical Engineering at Birmingham.
• Why?– Wanted to have an experiment as part of the control laboratories that showed something of what a modern PLC control interface would look like and something of what is technically possible in terms of remote operation.
Weblab – University of Birmingham
• How?– A lab experiment sheet was written to take the students through the use of the Weblab and then to look at estimating some suitable control parameters from performing step changes.
– It forms one of a series of labs the students look at. The other labs cover aspects of control more related to the taught material than the ‘real’ world.
Weblab – University of Birmingham
• Overall experience?– Staff/demonstrators: Has worked well, it is ‘low’ maintenance and the additional details available on the website allow the students to get a good feel for what the control equipment actually looks like and what it is for.
– Students: A very positive response, most like the idea of being able to control a rig in Cambridge, having the webcam means they can also see changes occurring.
Weblab – University of Birmingham
• Thanks to staff at Cambridge who have supported the Weblab use– Markus Kraft
– Andreas Braumann
– Mike Goodson
– Jon Etheridge
• And at Birmingham to Dr Chris Kent and various demonstrators.