Design Desirable Conditions for Inlet an

The aim of this work is to design a desirable condition for the ports of the inlet and outlet to establish the MILD regime in a lab-scale pre-heat furnace of the steel. The furnace is scaled down from 7MW to 10kW by the constant residence time approach to facilitate the design. In the initial furnace design, one fuel port was installed on the center of the vertical furnace surface along with four inlet air ports around it, and four outlets around the inlet airs. The target ingot temperature of 1250ºC and the ingot temperature uniformity is considered for the work’s main target points. Reduction in air mass flow rate of the bottom port leads to an increase in the ingot temperature from 1164ºC to 1174ºC, due to increasing the averaged gas temperature and mixing rate. Similarly, the reduction in the diameter of the top outlet yields close results to the air reduction, as it reduces the Damköhler number and increases the residence time. All cases exhibit a local MILD regime, but the reductions in air and outlet expand the MILD regime zone, with the effects of air reduction significantly surpassing those of outlet reduction.