Convective and conductive heat transfer in the bath under the arcs of high-power arc steel-melting furnaces

Abstract

We present the results of evaluation of the radiant heat flux emitted by an arc and incident on the surface of an ellipsoidal segment in the bath located under the arc, as well as the heat fluxes of the arc incident on the surfaces of slag and metal. We also present the results of evaluation of the arc energy spent during the period of oxidation for heating the metal and slag from temperatures of 1610 and 1670 °C to 1660 and 1750 °C, respectively. The amount of unmelted scrap metal during the period of its melting and the amount of energy spent for melting scrap metal on the slopes during the oxidation period were determined. Based on the numerical and experimental results, we plotted isotherms over the slag and metal surfaces at the end of the oxidation period in an electric-arc furnace (EAF). The slag temperature varies from 2500 °C in the hot zones under the arcs to 1650 °C in the peripheral zones on the slopes characterized by the presence of pieces of unmelted scrap metal under the slag layer. The temperature of the metal varies from 2735 °C in the hot zones under the arcs down to 1560 °C in the peripheral zones of location of unmelted charge on the slopes.