Capturing and suppressing resonance in steel casting mold oscillation systems using Timoshenko beam model

A methodology for development of high fidelity control-oriented continuous casting mold oscillator software testbed incorporating two coupled hydraulically actuated Timoshenko beam models is proposed. Nontrivial damped natural frequency calculation is carried out. For a finite-difference approximation of analytical model, monotonic dependence on spatial approximation accuracy of the resonance frequency under the fixed mass and of the mass under the fixed resonance frequency is discovered. Based on these findings, a novel beam parameter selection procedure for precise attainment of the desired resonance and damped natural frequencies by analytical and numerical models under the relevant boundary conditions and runtime constraints is developed. Using this procedure, fitting of the model parameters to resonance frequencies exhibited by thin and thick slab casting mold oscillators at the Nucor Decatur and Severstal Dearborn steel mills, respectively, is demonstrated. Assessment of controller efficacy in suppression of the undesirable oscillations in the software testbed fitted to Severstal caster is shown.

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