Coupled thermo-fluid stress analysis of Kambara Reactor with various anchors in the stirring of molten iron at extremely high temperatures

•A thermo-fluid coupling approach is proposed to analyze the thermal stress.•The temperature and stress of the impeller are 790 °C and 744 MPa at the final stage.•The highest temperatures occur at the tip of anchors, which causes material crack.•The thermal stress in impellers with Y-type anchors is greater than V-type anchors.

Kambara Reactors (KR) are commonly used to reduce sulfur content in steel making, achieving efficiency levels exceeding 85% at 1300 °C. Unfortunately, the operational lifespan of the KR impeller is somewhat limited due to fracturing of the refractory material via thermal shock, resulting in the penetration of molten iron into the inner core. Few studies have investigated the coupled thermo-fluid stress of KR impellers at extremely high temperatures. This study employed CFX and FEM to simulate and analyze the molten iron and the resulting thermal stress imposed on the KR impeller. Simulation results including flow field, temperature, and thermal stress under extremely high temperatures are in strong agreement with empirical data. V-type anchors for the KR impeller outperformed Y-type anchors.