Optimal control of free boundary of a stefan problem for metallurgical length maintenance in continuous steel casting

Zhelin Chen, Joseph Bentsman, Brian G. Thomas

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

An optimal control approach for minimizing metallurgical length deviation during casting speed increase under constraints on the secondary cooling flow rates for continuous steel casting process is proposed. The process is described as a single-phase Stefan problem. The temperature and the shell growth are controlled by the steel surface heat flux generated by the cooling sprays. A cost function reflecting the error in tracking of a reference shell thickness is chosen, and the control objective is formulated as the minimization of this cost function under the spray rate constraints. Finding the control law satisfying this objective is formulated as a two-step procedure. First, an analytical setting for the cost function minimization is established through deriving the corresponding direct, adjoint, and sensitivity systems. Then, a computational procedure for solving this analytical setting, which finds the actual control law, is given. A numerical example presents the application of the method proposed. The results are then extended to a 2D model, with the corresponding numerical example provided.

Original languageEnglish (US)
Title of host publication2019 American Control Conference, ACC 2019
PublisherInstitute of Electrical and Electronics Engineers Inc.
Pages3206-3211
Number of pages6
ISBN (Electronic)9781538679265
StatePublished - Jul 2019
Event2019 American Control Conference, ACC 2019 - Philadelphia, United States
Duration: Jul 10 2019Jul 12 2019

Publication series

NameProceedings of the American Control Conference
Volume2019-July
ISSN (Print)0743-1619

Conference

Conference2019 American Control Conference, ACC 2019
CountryUnited States
CityPhiladelphia
Period7/10/197/12/19

Fingerprint

Steel castings
Cost functions
Cooling
Heat flux
Casting
Flow rate
Steel
Temperature

ASJC Scopus subject areas

  • Electrical and Electronic Engineering

Cite this

Chen, Z., Bentsman, J., & Thomas, B. G. (2019). Optimal control of free boundary of a stefan problem for metallurgical length maintenance in continuous steel casting. In 2019 American Control Conference, ACC 2019 (pp. 3206-3211). [8815355] (Proceedings of the American Control Conference; Vol. 2019-July). Institute of Electrical and Electronics Engineers Inc..

Optimal control of free boundary of a stefan problem for metallurgical length maintenance in continuous steel casting. / Chen, Zhelin; Bentsman, Joseph; Thomas, Brian G.

2019 American Control Conference, ACC 2019. Institute of Electrical and Electronics Engineers Inc., 2019. p. 3206-3211 8815355 (Proceedings of the American Control Conference; Vol. 2019-July).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Chen, Z, Bentsman, J & Thomas, BG 2019, Optimal control of free boundary of a stefan problem for metallurgical length maintenance in continuous steel casting. in 2019 American Control Conference, ACC 2019., 8815355, Proceedings of the American Control Conference, vol. 2019-July, Institute of Electrical and Electronics Engineers Inc., pp. 3206-3211, 2019 American Control Conference, ACC 2019, Philadelphia, United States, 7/10/19.
Chen Z, Bentsman J, Thomas BG. Optimal control of free boundary of a stefan problem for metallurgical length maintenance in continuous steel casting. In 2019 American Control Conference, ACC 2019. Institute of Electrical and Electronics Engineers Inc. 2019. p. 3206-3211. 8815355. (Proceedings of the American Control Conference).
Chen, Zhelin ; Bentsman, Joseph ; Thomas, Brian G. / Optimal control of free boundary of a stefan problem for metallurgical length maintenance in continuous steel casting. 2019 American Control Conference, ACC 2019. Institute of Electrical and Electronics Engineers Inc., 2019. pp. 3206-3211 (Proceedings of the American Control Conference).
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