Research Article Bifurcated SEN with Fluid Flow Conditioners F. Rivera-Perez, 1 C. Real-Ramirez, 1 R. Miranda-Tello, 2 R. Hernandez-Santoyo, 1 F. Cervantes-de la Torre, 1 and J. Gonzalez-Trejo 1 1 Departamento de Sistemas, Division de Ciencias Basicas e Ingenieria, Universidad Autonoma Metropolitana—Azcapotzalco, Avenida San Pablo 180, Col. Reynosa-Tamaulipas, Del. Azcapotzalco, 02200 Mexico, DF, Mexico 2 Departamento de Electronica, Division de Ciencias Basicas e Ingenieria, Universidad Autonoma Metropolitana—Azcapotzalco, Avenida San Pablo 180, Col. Reynosa-Tamaulipas, Del. Azcapotzalco, 02200 Mexico, DF, Mexico Correspondence should be addressed to J. Gonzalez-Trejo; jesus.glez.t@gmail.com Received 29 November 2013; Accepted 15 April 2014; Published 30 June 2014 Academic Editor: Yonghong Wu Copyright © 2014 F. Rivera-Perez et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Tis work evaluates the performance of a novel design for a bifurcated submerged entry nozzle (SEN) used for the continuous casting of steel slabs. Te proposed design incorporates fuid fow conditioners attached on SEN external wall. Te fuid fow conditioners impose a pseudosymmetric pattern in the upper zone of the mold by inhibiting the fuid exchange between the zones created by conditioners. Te performance of the SEN with fuid fow conditioners is analyzed through numerical simulations using the CFD technique. Numerical results were validated by means of physical simulations conducted on a scaled cold water model. Numerical and physical simulations confrmed that the performance of the proposed SEN is superior to a traditional one. Fluid fow conditioners reduce the liquid free surface fuctuations and minimize the occurrence of vortexes at the free surface. 1. Introduction Increasing cleanliness of the steel slabs produced in con- tinuous casting machines remains one of the priorities of the steel industry [1–3]. Ensuring product quality requires understanding a set of highly coupled phenomena. Several works have studied some of these phenomena separately [1, 4–9]. Researchers from academia and industry recognize that the fuid fow pattern in the mold signifcantly afects the quality of the steel produced in continuous casting machines [10–13]. However, the fuid fow pattern inside the mold in turn depends on several factors such as the confguration of the valve that connects the tundish with the submerged entry nozzle (SEN), the internal geometry of the SEN, the SEN submergence depth, the dimensions of the mold, and casting speed. Te many fuid fow patterns observed inside the mold could be grouped on three general types: double roll, unsteady, and single roll [14]. Te preferred pattern is the double roll because it produces an equal distribution of mol- ten slag layer over the entire width of the mold. In addition, the product displays the minimum number of steelmaking defects. Te design of the internal geometry of the SEN aims to induce a double roll fuid fow pattern inside the mold. Despite this, wrong operation conditions trigger a single roll or an unsteady fuid fow pattern. Some characteristics of an unsteady fow pattern are high mold level fuctuations, uneven molten slag layer thickness, and vortexing [14]. All these features signifcantly degrade the quality of the solid- ifed steel (for instance, mold powder-based slivers, uneven solidifcation shell, and longitudinal cracks). Te mechanism for transition from the double roll to an unsteady fuid fow pattern remains uncertain. Several approaches have been used to damp fuctuations of the interface between molten slag and liquid steel in slab continuous casting. One of them is to impose an electromag- netic feld across the mold to change the fow pattern [15, 16]. Tis technology is the most commonly used, but it has several drawbacks associated with it; for example, it is sensitive to operating conditions, costly, and difcult to operate. Immersing external refractory shapes in the mold is another approach recently proposed by Kamal and Sahai [17]. Hindawi Publishing Corporation Mathematical Problems in Engineering Volume 2014, Article ID 809526, 12 pages http://dx.doi.org/10.1155/2014/809526