Simulated second-order moments of clusters and dispersed particles in riser

Abstract The second-order moment model for solid phase combining with large eddy simulation for gas phase was used to simulate distribution of moments and volume fraction of particles in the riser. This study shows that the simulated solids volume fractions along height using a two-dimensional model are in agreement with experiments. The axial second-order moments are larger than the lateral second-order moment by 2–3 times. The second-order moments of clusters and dispersed particles are calculated. Simulations show that the second-order moment of dispersed particles is about 3.9 times larger than that of clusters in axial direction. The simulated second-order moments of clusters and dispersed particles increase with the increase of superficial gas velocity and solids mass flux. The particle–particle collisions result in the reduction of anisotropic profiles for the solid phase in risers. Anisotropy of the normal second-order moments increases with the increase of superficial gas velocity. Both axial and lateral second-order moments increase with the increase of diameter of particles.