Dynamics and thermodynamics of multimorphological particles in the blast furnace raceway

Abstract Coke morphology modulates multiphase transport in raceway flows by influencing thermo-fluid behavior and heat transfer performance. This study employs the Discrete Element Method–Computational Fluid Dynamics (DEM–CFD) approach to analyze the effects of particle shape on raceway structure and heat transfer. The applicability of the method was validated against experimental data, and the accuracy of the Coarse-Grained Particle Model (CGPM) was assessed. Comparative analysis revealed particle shape effects on raceway dynamics. Results indicate that CGPM significantly reduces computational costs while preserving dynamics and thermodynamics consistent with those of the original particle systems in raceways. Spherical and pyramidal particles form enlarged raceways, facilitating deadman formation through accumulation at the furnace hearth center. In contrast, three other non-spherical morphologies reduce raceway dimensions yet enhance convective heat transfer. Ellipsoidal particles suppress temperature rise, while pyramidal particles induce fragmented fluidization at the raceway top with velocity-dependent instabilities. Raceway size inversely correlates with drag force and heat transfer rate. These findings advance the understanding of dynamic and thermo-fluid behaviors of non-spherical particles in raceways.