Using a Numerical Model to Study the Transient Clogging Phenomena in SEN During Continuous Casting of Steel M. Wu 1* , H. Barati 1,2,3 , A. Kharicha 1,3 , A. Ludwig 1 1 Chair for Modeling and Simulation of Metall. Processes, Dept. Metall. Montanuniversitaet Leoben, Franz-Josef Street 18, 8700 Leoben, Austria *Email: menghuai.wu@unileoben.ac.at 2 K1-MET Franz-Josef Street 18, 8700 Leoben, Austria 3 Christian-Doppler Laboratory for Metallurgical Applications of Magnetohydrodynamics, Dept. Metall. Montanuniversitaet Leoben, Franz-Josef Street 18, 8700 Leoben, Austria Keywords: clogging, non-metallic inclusion, submerged entry nozzle (SEN), solidification, continuous casting INTRODUCTION Clogging of submerged entry nozzle (SEN) is one problem, which annoys metallurgists since 1960s as the technology of steel continuous casting appeared [1]. Despite of vast research efforts on this topic both experimentally [1-6] and numerically [6-8], no reliable and efficient method is available for the steel industry to eliminate it. The current authors have recently pub- lished a numerical model for the nozzle clogging [9-11]. Following phenomena of clogging were considered: transport of the non-metallic inclusions (NMIs) as particles in the turbulent flow of steel melt; deposition of the NMIs and buildup of the initial layers of clog on the SEN wall; continuous growth of clog region (as porous medium) due to further deposition of NMIs; the interaction of the clog region with the melt flow; possible solidification of steel melt in the porous clog region. This contribution is to present a test simulation of industry scale based on this model. The aim is to explore the model capa- bilities or limitations. The coincidence/agreement between the numerical simulations and the industry observa- tions/experience will be discussed, leading to an outlook of the open topics for further study. NUMERICAL STUDY Model in brief The key mechanism as considered in this clogging model is the transport and deposit of indigenous non-metallic inclusions (NMIs), as de-oxidation products in the steel melt, towards/on the SEN wall, leading to a gradual build-up of clog layer. An Eulerian-Lagrangian approach is used to track the motion of NMIs. The morphology of NMIs is assumed spherical. To han- dle the turbulence effect on the NMI motion, a standard random walk model is used in the bulk melt region; while in the near-wall region a stochastic coherent-structure model for particle deposition is used [12]. As soon as the NMIs hit the SEN wall, it is assumed to be captured by the wall. At the early stage, the deposition of NMIs on the SEN wall is just treated as a part of the SEN wall roughness, whose height increases with the further NMI deposition. When the roughness height exceeds half of the computational cell (boundary), the clog layer is treated as porous medium, i.e. the boundary cell is considered to be partially-filled porous medium. An algorithm is implemented to track the clog growth, i.e. the further deposition of NMIs on the clog front. The clog region interacts with the fluid flow. The melt can flow through the clog region, and the permeabil- ity of the clog depends on its porosity. This parameter (porosity) cannot be determined by the current model. It must be pre- defined experimentally through the postmortem analysis of the as-used SEN. Details of the model were described elsewhere [9-11]. Proceedings of the 8th International Conference on Modeling and Simulation of Metallurgical Processes in Steelmaking (STEELSIM 2019) 13–15 August 2019, Toronto, Ont., Canada © 2019 by the Association for Iron & Steel Technology. 664 DOI 10.33313/503/069