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Calculation of the effect of polymer additive in a converging flow

Published online by Cambridge University Press:  21 April 2006

G. Ryskin
Affiliation:
Department of Chemical Engineering, Northwestern University, Evanston, IL 60201, USA

Abstract

The conical-channel flow of a dilute polymer solution is investigated theoretically. The stress field due to polymer additive is calculated using a new molecular model, based on the physical picture of the polymer molecules unravelling in strong flows and Batchelor's theory for the stress in a suspension of elongated particles. Good agreement is obtained with the experimental results of James & Saringer (1980). The absence of a significant polymer effect in a two-dimensional case (the wedge-channel flow), observed by the same authors (James & Saringer 1982a), is also explained. The fundamental differences between the proposed model and the elastic-dumbbell models are discussed.

Type
Research Article
Copyright
© 1987 Cambridge University Press

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