Numerical investigation on the mutual interaction between heat transfer and non-spherical particle dynamics in the blast furnace raceway

•Investigate the interaction between heat transfer and microstructure of the raceway.•Explore the burden descending process with the coke particle discharged near the tuyere.•Discuss the effect of particle shape and inlet gas velocity on raceway evolution and heat transfer. In this paper, the coupled computational fluid dynamics (CFD) and discrete element method (DEM) scheme is used to investigate the microstructure and heat transfer characteristics in a blast furnace (BF) raceway. The impact of gas velocity and particle shape on raceway evolution, microstructure characteristics, and particle temperature and voidage distributions is comprehensively explored based on the voidage change caused by the consumption of coke particles. Numerical results show that the oblate ellipsoidal particle system possesses higher average voidage in the original packing state and implements the faster burden descending rate than the prolate one under the same inlet velocity. For the non-spherical particle systems, larger contact forces exist in the oblate ellipsoidal particle system while the contact forces in the prolate ellipsoidal particle system are smaller. More uniform temperature distribution and higher average voidage can be caused by higher inlet gas velocities. Meanwhile, more prolate ellipsoidal particles are consumed than oblate ones under the same inlet velocity. These findings could be beneficial for understanding the kinetic and thermodynamic behaviors of particulate system within a BF raceway. [Display omitted]