Toward a Simplified Arc Impingement Model in a Direct-Current Electric Arc Furnace

Abstract

A 2D axisymmetric two-phase model was developed to study the effect of an arc impingement on the liquid metal inside an electric arc furnace. In addition to the arc flow dynamics, the model covered the heat transfer and magneto hydrodynamics of the arc and the liquid metal. Through a parametric study, three different parameters were considered to predict the most important factors affecting the arc and overall behaviour of the process: the arc gap, the density of the gas, and the total electric current. Understanding the effect of these parameters can show the key factors altering the arc dynamics. The study showed that the total applied current was the most important parameter that influenced the impingement depth and mixing of the liquid metal. The depth of the impingement and strength of the mixing of the liquid bath were directly proportional to the current applied in the furnace. The initial arc gap distance was found to be crucial for sustaining a continuous and stable arc. The value of the gas density was very important for the velocity profile; however, it had no significant effect on the impingement depth. This showed that a constant density could be used instead of a varying gas density with temperature to increase the computational efficiency. The study assessed the effects of the aforementioned factors on the arc impingement depth, velocity magnitude, and arc stability. The conclusions acquired and challenges are also presented.

A Numerical Study on the Influence of External Magnetic field on Hydrogen Electric Arc Flow

“…this assumption allows to model the arc separately. The flow, temperature, and electromagnetic equations were solved [17]. The LES model is used to model turbulence [18].…”

“…The vector field shows current path and direction. The transparent white surface is the isothermal surface of 10 000 K. Electrical conductivity is temperature dependent and 10000 K is considered the border line where arc exists at T>10000 K. The arc initially develops the well-known bell shape structure at time 0.00032 s. Small instabilities start at the cathode spots at t = 0.0005 s. The current entering to the cathode from the arc region interacts with the self-induced magnetic field and induces a Lorentz force that creates a powerful jet downwards [17]. Small instability develops rapidly and travels downwards along the current path.…”

Exploring Extreme Voltage Events in Hydrogen Arcs within Electric Arc Furnaces

“…The model was previously validated and compared to the previous literature [33][34][35], and the time average results of temperature and magnetic field were calculated for the incompressible model. The obtained results were compared with the steady-state results predicted by Alexis et al [14], Figure 3a,b.…”

Modeling and Simulation of Metallurgical Processes in Ironmaking and Steelmaking

“…The model was validated using steel temperature and weight measurements achieving reasonable agreement. Al Nasser et al [10] developed a simplified arc impingement model to study the direct-current electric arc in computational fluid dynamics simulations. The model was used to investigate the influence of the factors arc gap, the density of the gas and total elec-tric current on the behaviour of the arc, and the overall process, including arc impingement depth, velocity magnitude, and arc stability.…”