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Control of a surface of discontinuity in continuous thickness

Published online by Cambridge University Press:  17 February 2009

N. G. Barton
Affiliation:
CSIRO Division of Mathematics and Statistics, P.O. Box 218, Lindfield, NSWAustralia2070.
C.-H. Li
Affiliation:
CSIRO Division of Mathematics and Statistics, P.O. Box 218, Lindfield, NSWAustralia2070.
S. J. Spencer
Affiliation:
CSIRO Division of Mathematics and Statistics, P.O. Box 218, Lindfield, NSWAustralia2070.
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Abstract

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This paper examines the control of an interface between a suspension of sedimenting particles in liquid and a bed of dense-packed particles at the bottom of the suspension. The problem arises in the operation of continuous thickeners (e.g. in mineral processing) and is here mathematically described by a first order inhomogeneous partial differential equation for the concentration C(x, t) of particles. The controlled variable is the height H* of the bed, and the control variables are the volume fluxes injected at the feed level and removed at the bed. A strategy to control the interface is devised, and control is confirmed and demonstrated by a series of numerical experiments.

Type
Research Article
Copyright
Copyright © Australian Mathematical Society 1992

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