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A regulator for continuous sedimentation in ideal clarifier-thickener units. (English) Zbl 1133.76045

Summary: The purpose is to present a regulator for control of continuous-sedimentation process in a clarifier-thickener unit when this is modelled in one space dimension and when the settling properties of the solids obey Kynch’s assumption. The model is a scalar hyperbolic conservation law with space-discontinuous flux function and point source. The most desired type of solution contains a large discontinuity. A common objective is to control the movement of this discontinuity subject to the requirement that the effluent of the process have zero concentration of particles. In addition, there may be a requirement that the underflow concentration of the thickened suspension lie above a predefined value. Based on previous results on the nonlinear behaviour of the process [the author, SIAM J. Appl. Math. 56, No. 2, 388–419 (1996; Zbl 0849.35142)], a nonlinear regulator is presented. It controls the location of the large discontinuity indirectly by controlling the total mass. The process is stabilized significantly and large input oscillations can be handled.

MSC:

76N25 Flow control and optimization for compressible fluids and gas dynamics
76T20 Suspensions

Citations:

Zbl 0849.35142
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Full Text: DOI

References:

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