PW hopper is the vital transition equipment in the whole blast furnace operation unit, it is of great significance to deeply analyze the influencing mechanism of the hopper to control the stable discharge rate and stabilize furnace condition. To date, there is a lack of structural analysis that affects the change of mass flow rate in PW hopper discharging process and the application of formula for predicting mass flow rate. In order to control and optimize the discharging process of PW hopper better, the orthogonal section method was applied to analyze the velocity field and the contact force field distribution of the whole hopper and the cone part based on DEM, and the correlated Beverloo equation with flow bulk density term was applied to predict the mass flow rate (MFR) of the steady-state discharging process for the first time. The results show that: (a) there is a strong difference in flow velocity in the cone section that leads to the velocity exchange of particles, which explains for the first time that the asymmetrical structural design of the hopper is conducive to avoiding funnel flow; (b) the trend of mass flow rate predicted under the correlated Beverloo equation is the same as that obtained by DEM, and the fluctuation range of mass flow rate between the two is 0.05~1.7 kg/s, and the minimum relative error is only 2.7%.
 

PW hopper, DEM, Asymmetric structure, Discharging process, Flow pattern, MFR