An in-line process rheometer, employing a proven shear-stress transducer, was designed and built for polymer melts. The entire process stream runs through the rheometer, giving it a much faster response time than conventional side-stream models. The possibility of using the in-line rheometer for dynamic mechanical analysis was investigated and methods were developed to obtain the complex modulus over a wide range of frequencies with a single measurement. Measurement techniques for shear viscosity testing were also developed along with algorithms to compensate for the effects of process pressure and temperature. / The rheometer was used as a viscosity sensor to provide feedback control for a polypropylene visbreaking process. A first order plus dead time model was used to model the process and the rheometer together, and typically had dead times of less than 60 s and a first order time constant of 15 s. Gain scheduling was incorporated into minimum variance and proportional-integral controllers to achieve closed-loop settling times of 200 s for viscosity setpoint changes and process disturbances.
Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.28499 |
Date | January 1994 |
Creators | Nelson, Burke I. (Burke Irving) |
Contributors | Dealy, J. M. (advisor), Patterson, W. I. (advisor) |
Publisher | McGill University |
Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
Language | English |
Detected Language | English |
Type | Electronic Thesis or Dissertation |
Format | application/pdf |
Coverage | Doctor of Philosophy (Department of Chemical Engineering.) |
Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
Relation | alephsysno: 001425260, proquestno: NN00117, Theses scanned by UMI/ProQuest. |
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