CONTUN - Controller Tuning Problem

The temperature of a continuous flow of material through a steam-heated stirred tank is controlled by regulating the flow of steam. The tank temperature is measured by a thermocouple set inside a thermowell, giving a delayed temperature measurement response. This example is based on that of Robinson (1975). 

The temperature of both thermocouple and thermowell are each described by first-order lag equations, so that  

Lambda=537 Ws0 = 0.2 Kc=l.5 TRset = 4 0 TAUc=0.1 TAUw=0.3 TAUi=5 Time CINT=0 INTERACT  

Feed temperature Latent heat of vaporization Average steam mass flow Proportional gain Set temperature of tank Time constant of thermocouple Time constant of thermowell constant of integral control 1,TFIN=30,NOCI=3 RESET GOTOl 

Controller Constant Constant Constant Constant Constant Constant Constant Constant Constant Constant Constant Constant 1 SIM  

5 Simulation Tools and Examples of Chemical Engineering Processes 

Allow the tank to achieve steady-state operation in the absence of control (Kp = 0). Use the resulting process reaction curve to estimate combined proportional and integral control parameters. Then use the obtained steady-state values as the initial values for a following sequence of runs. 

Experiment with the influence of different values of the measurement time constants, Xc and X v, Plot all the temperatures to compare the results. 

Robinson, E.R. (1975) Time Dependent Processes, Applied Science Publishers. 

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