Numerical Simulation on Phenomena of Fine Particles Passing through an Orifice under Gas Flow Condition

Under low reducing agent rate and high pulverized-coal injection rate operations, coke powder and unburnt char are generated in the blast furnace. These powders flow through the packed bed inside the furnace entrained by the gas flow. The powders accumulation in packed bed will deteriorate gas and liquid permeability and creates an unstable situation inside the blast furnace. Thus, it is important to quantitatively evaluate the accumulation rate on a distribution channel of coke powders. In this study, the behavior of the powder particles passing through the orifice formed by three coarse particles that osculate one another and compound in an equilateral triangle was numerically analyzed using the DEM-CFD. The results revealed the effect of drag force on the powder motion passing through the orifice. Moreover, the effect of the position of the powder passing through the orifice to pressure drop fluctuation inside the triangular prism is also analyzed.