MODELLING OF A POLYMER REACTOR

An automated pilot-scale 1-litre experimental polymer reactor system with facilities for on-line measurement of flow rate, temperature and density has been set up by Chien and Penlidis (1994a, b). These authors describe a set of open-loop process identification experiments and closed-loop control experiments performed on this system where monomer conversion is controlled in the presence of reactive impurities using the initiator flow rate as the manipulated variable. 

Since the polymer reactor is known to be nonlinear and there are noticeable differences between the two step responses, two separate Laguerre models are estimated from the data. The model order is chosen to be 3 for both 

The settling time of the first step response is estimated to be approximately 200 sec and therefore the search interval for the optimal time scaling factor p is chosen to be (2U0 interval is divided into 17 discrete values 

By substituting Equation (2.113) into the definition of the Fourier transform we have 

An equivalent result to Equation (2.85) can be obtained by taking the Laplace transform of the derivatives of the Laguerre functions. It can be readily shown that, from the state space representation of the Laguerre network in Equation (2.19) 

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