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This paper presents examples from the practice of operating arc steel-smelting furnaces (EAFs), verifying the hypothesis on the complex heat exchange of arcs in spherical segments in the bath. The thermal radiation of arcs in spherical segments is converted into convective and thermal conduction flows, heating the entire volume of metal and slag. No more than 3%–4% of the arc power is spent on evaporation of the metal under the arcs, while 76–78% of the arc power is converted into convective and thermal conduction flows that heat the bath. The metal waste under the arcs is 8–9%, in which 91–92% of the metal waste is accounted for in the zones of exposure to the bath with oxygen. With an oxygen consumption of 10–15 m3/t in the EAF, metal waste is 3%; with an increase in oxygen consumption to 50 m3/t, metal waste increases by 2.5–4 times to 7.5–12%. With an increase in the absorption coefficient of the gaseous atmosphere of the DSP-100 furnace, the maximum density of thermal radiation fluxes from the arcs to the walls decreases proportionally. With an increase in the height of the slag layer by 3.7 times, the maximum density of thermal radiation fluxes of the arcs on the water-cooled wall panels decreases by 2.6 times. [ABSTRACT FROM AUTHOR]

This paper presents the results of experimental studies of heat transfer in electric arc furnaces, which showed that heat fluxes incident from arcs on a heating surface comprise 85%–95% of thermal radiation fluxes. The thermal radiation laws of ionized and nonionized gas volumes are stated, according to which the heat transfer in electric arc furnaces is calculated. The experimental and calculated data on the heat fluxes of arc radiation on a heating surface differ by no more than 5%–8%, indicating that the thermal radiation laws of gas volumes correspond to real heat transfer processes in electric arc furnaces. The heat exchange of arcs in an electric arc furnace bath was calculated. When the arcs are completely buried in the recesses of the bath, their slag and heat radiation fluxes are converted in the recesses into convective heat fluxes and heat conduction flows, heating the entire volume of the metal bath and slag. [ABSTRACT FROM AUTHOR]