Heat transfer by convection and conduction in the bath beneath the arcs of high-power arc steel-melting furnaces. Part 1. Laws of thermal radiation of gas volumes in arcs and flames and their use for calculating heat transfer in electric arc furnaces (EAF)

Abstract

The results of the analysis of heat sources entering a high-power electric arc furnace are presented. Electric arcs are the primary heat sources in such furnaces. Heat transfer from the ionized gas volumes of arcs and the non-ionized gas volumes of flames from oxy-fuel burners to the heating surfaces in an electric arc furnace (EAF) occurs through thermal radiation. A significant error in calculating the heat transfer of gas volumes in arcs and flames to heating surfaces using the law of thermal radiation of blackbodies, i.e., the Stefan-Boltzmann law, has been demonstrated. The laws of thermal radiation of gas volumes in electric arcs and flames in EAFs, discovered in Russia between 1996 and 2001, are presented. According to these laws, cylindrical gas volumes are inscribed within the gas volumes of arcs and flames, and in calculations, their thermal radiation is modeled with high accuracy as the thermal radiation of cylindrical axes of symmetry. Based on the discovered laws, a method for calculating heat transfer in EAFs has been developed. The results of arc parameter calculations and the principle of converting the radiative heat flux into powerful convective and conductive heat flows during the turbulent movement of slag and metal in the bath are presented.