Korean Journal of Chemical Engineering, Vol.15, No.1, 45-50, January, 1998
TIME-OPTIMAL CONTROL OF MMA-MA COPOLYMERIZATION IN A CSTR FOR GRADE CHANGE
The time-optimal control of MMA-MA copolymerization in a CSTR is treated for a grade-change operation. The control objective is to bring system specifications, such as polymer production rate and polymer composition, to desired values in minimum time. The initiator concentration is chosen as a manipulated variable. Two cases are considered : One is to get the time optimal control for both a desired polymer production rate and a desired weight composition of MA in dead copolymer; the other is only for a desired polymer production rate. In numerical calculation, the final tf(i) is chosen at each iteration as the time at which the system reached steady-state. This allows us to use a more easily manipulatable form of the performance index and at the same time not directly use the free final time boundary condition.
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