Process Dynamics Modeling: Empirical vs Theoretical Approaches
This guide covers essential aspects of process dynamics modeling, including empirical and theoretical dynamic models. Empirical models rely on data fitting within a specific operational range, making them valuable for predicting process behavior under known conditions. In contrast, theoretical models are based on fundamental theories, aiding in controller tuning and extrapolation beyond measured data. The section also presents a detailed approach to modeling a stirred tank heater process, including system block diagrams and feedback loops, essential for understanding energy transfer and process control.
Process Dynamics Modeling: Empirical vs Theoretical Approaches
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Presentation Transcript
CBE / MET 433 15 Feb 12 (Chapter 3: Process Modeling) • Models of Process Dynamics • Empirical Dynamic Models: can frequently describe process dynamics, but are “data fits” over a specific range of operation. • Theoretical Dynamic Models: are based on theory and might be useful for extrapolating. Also can be useful for determining controller tuning. Accuracy depends upon model details.
T Sensor Transducer
Develop System Block Diagram Transmitter http://www.omega.com/thermocouples.html TE selection guide Type T TC
Develop System Block Diagram Transmitter Transducer
Develop System Block Diagram Transmitter Transducer Valve
Develop System Block Diagram Transmitter Transducer Valve Energy Transfer
Develop System Block Diagram Transmitter Transducer Valve Energy Transfer Controller
Develop System Block Diagram Transmitter Transducer Valve Energy Transfer Controller Process
Feedback Block Diagram Transmitter Transducer Valve Energy Transfer Controller Process
Feedback Block Diagram + + + -
Open Loop vs Closed Loop Transfer Function (R(s)=0) Open Loop: + + + - Closed Loop:
Transfer Functions (Chap 3-5) Define: For heated, stirred tank: + + + + + + - -
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