A Three-Dimensional Multiphysics Coupled Model of Melting and Rotation of the Electrode During Electroslag Remelting Process

A transient three-dimensional (3D) coupled model is developed to investigate the melting and rotation of the solid electrode during the electroslag remelting (ESR) process. The large eddy simulation (LES) method is utilized to model the multiphase flow. The slag/metal interface is precisely tracked utilizing the volume of fluid (VOF) approach with an adaptive mesh refinement strategy. The model pays specific attention to the shape evolution of the electrode tip, as well as the formation and motion of droplet under different electrode rotating speeds. The accuracy of the model is validated by an additional transparent experiment. As the electrode rotates, the centrifugal force pushes the randomly dispersed faucets underneath the electrode outwards until reaching the periphery. The electrode rotation flattens the electrode tip, reducing the horizontal deviation of its profile by up to 69.9 pct compared to a static electrode. As the electrode rotating speed increases from 0 to 60 rpm, the thickness of liquid metal film decreases from 0.91 to 0.63 mm, while the equivalent diameter of droplets decreases from 12.90 to 11.77 mm. The electrode rotation increases the specific surface area, dramatically improving the removal efficiency of inclusions and harmful elements. Moreover, productivity reached a maximum of 21.56 pct at a rotating speed of 60 rpm without increasing power input.