Browsing by Author "Butala, D."

Now showing 1 - 4 of 4
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    Control of Batch Free Radical Polymerization Reactors.
    (1987) Choi, Kyu Y.; Butala, D.; ISR
    This paper describes a new approximation method to synthesize open loop control schemes for the control of copolymer composition and molecular weight in batch and semibatch polymerization reactors. The open loop control policies are derived from the transient response of the fictitious feedback control system obtained by numerical model simulations. The applicability of the proposed method is demonstrated through numerical examples.
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    Control or Batch Free Radical Polymerization Reactors.
    (1987) Choi, Kyu Y.; Butala, D.; ISR
    This paper describes a new approximation method to synthesize open loop control schemes for the control of copolymer composition and molecular weight in batch and semibatch polymerization reactors. The open loop control policies are derived from the transient response of the fictitious feedback control system obtained by numerical model simulations. The applicability of the proposed method is demonstrated through numerical examples.
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    A Design of Optimal Control System for Semibatch Free Radical Copolymerization Reactors by Inverse Feedback Control Technique.
    (1986) Choi, Kyu Y.; Butala, D.; ISR
    A novel Inverse Feedback Control technique is proposed for the design of optimal open loop control system in semi-batch free radical copolymerization process in which on-line polymer property sensors are absent. The open loop polymer quality control problem is converted to the closed loop controller design problem in which "fictitious" on-line polymer property sensors are assumed to be available. The time varying trajectories of reactor manipulated variables in such "fictitious" feedback control system are found to be equivalent to the optimal trajectorios of control variables or set point programs required in the original open loop control system. The proposed technique can also be easily applied to the design of multivariable open loop systems for nonisothermal semi-batch copolymerization processes. The validity and the applicability of the proposed technique based on "knowledge learning" principle are illustrated through the numerical examples of semi-batch copolymerization process control.
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    Multiobjective Dynamic Optimization of Semibatch Free Radical Copolymerization Proceas with Interactive CAD.
    (1987) Butala, D.; Choi, Kyu Y.; Fan, Michael K-H.; ISR
    Optimal open loop control strategies are developed for batch and semibatch free radical copolymerization of styrene and acrylonitrile using the interactive computer aided design (CAD) tool CONSOLE, which was developed at the University of Maryland in 1987. CONSOLE emphasizes control engineer's intuition and man- machine interaction and includes a classification of various design specifications. Conflict resolution among the different objectives is made by scaling of specification space based on designer's knowledge of the polymerization proceas. A feasible direction algorithm is used to obtain optimal monomer addition and reactor temperature policies.