Stress fields of solid flow in a model blast furnace

The computational fluid dynamics-discrete element method approach, supported by an averaging technique, has been employed to quantitatively investigate the stress distributions of solid flow in a model blast furnace (BF). The results indicate that large normal stresses are mainly observed in the lower central part of the BF, whilst small normal stresses in the vicinity of the raceway. In the upper part, the vertical normal stress varies little horizontally in the central region but reduces a bit near the wall, whereas the horizontal normal stress has a relatively uniform distribution on the whole cross section. The shear stress has its largest magnitude in two symmetrical regions close to the stagnant zone. The couple stress can be ignored except for the regions close to the walls. The stress and couple stress are both affected by gas flow rate. In particular, increasing gas flow rate will decrease the magnitude of the stress and couple stress. The internal friction coefficient is not dependent on the inertial number for the solid flow in a BF, but it may rely on the inertial number in some specific flow regions for the cases without gas and with low gas flow rates.