Numerical Investigation on Electromagnetism and Heat Transfer in Electroslag Remelting Process with Triple- Electrode

다국어 초록 (Multilingual Abstract)

A transient three-dimensional (3D) model is developed for understanding the electromagnetism, heat transfer and phase change in electroslag remelting (ESR) furnace with triple-electrode. The electromagnetic fields are solved by Maxwell’s equations using the finite element method. The temperature field and phase change are modeled by the enthalpy approach. A reasonable agreement is obtained between experiment and simulation. The electric current flows from one electrode into the slag and comes out from other two electrodes. Most electric current travels through the slag near the slag/ingot interface. A great amount of the Joule heating is generated by the slag and a higher value is found in the slag around the three electrodes. The highest temperature is located at the center of the slag layer. Increase in the current causes the increase in the Joule heating. A hotter slag and a deeper metal pool therefore are formed. The total Joule heating in the slag increases with more slag, while the average Joule heating density reduces.
The metal pool depth increases and then decreases with the increasing slag thickness, and the deepest metal pool is obtained at the slag thickness of 200 mm. The power efficiency and the slag temperature reduce with the increasing electrode immersion depth. A shallower electrode immersion depth is a better choice for the ESR process with triple-electrode.

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