Research on fluid flow and heat transfer in electromagnetic induction heating RH

Molten steel temperature drop adversely affects the Rheinstahl-Heraeus (RH) vacuum treatment, a key secondary refining process for high-quality steel. To address this, the electromagnetic induction heating RH (RH-EMIH) system has been proposed to compensate for temperature losses. In this paper, the fluid flow and heat transfer phenomena in RH-EMIH are investigated for the first time by combining water model experiment with numerical simulation. A novel coupled mathematical model is also developed to systematically analyze the interplay among Joule heating, electromagnetic stirring, and thermal behavior. The results show that the predicted flow field and temperature field agree well with the experimental data. Specifically, the electromagnetic force intensifies radial flow and recirculation flow, leading to a distinct spiral flow pattern in up snorkel. Under electromagnetic induction heating, the molten steel temperature rises progressively as it circulates in RH-EMIH, achieving an increase of approximately 31 K after 25 minutes of vacuum treatment. The Joule heat provides efficient temperature compensation for molten steel, with the maximum temperature zone observed at the bottom of down snorkel. Furthermore, the molten steel temperature in RH-EMIH rises linearly with induction heating power, increasing by approximately 6, 12, 18, 25, and 31 K at 400, 800, 1200, 1600 and 2000 kW, respectively. These findings demonstrate the strong potential of RH-EMIH for enhancing temperature control and refining efficiency in industrial applications. • Joule heat provides efficient temperature compensation for molten steel. • Molten steel temperature increases about 31 K after 25 minutes. • Electromagnetic force enhances radial flow and recirculation flow. • Molten steel temperature rises linearly with induction heating power.