Effect of particle shape on raceway size and pressure drop:
experimental, numerical and theoretical analyses
Abstract
Experiments and simulations are conducted to explore the changing laws
of blast furnace raceway morphology and pressure drop with cylindrical
particles. Experimental data show that there are five typical stages for
the pressure drop during the raceway formation. The closer the aspect
ratio (Ar) of particle to 1, the bigger the raceway size and the wider
the particle moving band will be. When the raceway is in stable stage,
the pressure drop can be ascribed to the cooperative action of the bed
height, inlet gas velocity and Ar. Numerical results reveal that the
large raceway formation for sphere-like particle is due to the small
drag and contact forces. The contact forces in the prolate particle
system are very large and thus result in a small raceway. Finally, the
influence of particle shape is employed to improve a raceway size
predictive correlation which can increase the average calculational
accuracy by 3.4%.