Abstract
Application of discrete element method (DEM) to blast furnace attracts special interest, because the accurate solid motion analysis in the blast furnace is feasible by DEM. In the previous studies in this area, although the descending velocity and physical parameters of particle in DEM were important factors for accurate solid motion analysis, a priori assumptions were frequently introduced to the calculations. In this study, the sensitivities of these parameters were cautiously examined on the basis of cold model experiments. The favorable combination of contact and rolling frictions was introduced to represent the shape of particles. A scale-down three-dimensional cold model of blast furnace was used for analyzing motion of polyethylene and coke particle to confirm the influence of these coefficients. Accordingly, the relationship between the descending behavior of particle and the rolling friction coefficient became clear by comparison of model experiments and DEM simulation. Basically, the rolling friction coefficient is dependent on diameter of particle. In these experimental results, the reduced descending velocity in the packed bed had little influence on the burden descending behavior. It was estimated that the calculated results by DEM in the reduced time scale could quantitatively show the burden behavior in the actual blast furnace. DEM calculation with the appropriate parameters is profitable for the macro flow and local particle behavior analyses in the blast furnace.
