Study of the hydraulic transport of non-spherical particles in a pipeline based on the CFD-DEM

Slurry pipeline transport, which is widely used in dredging, is an important method of solid material transportation. The internal structure information of flows with different shaped particles must be obtained to investigate the effects of different particle shapes on the efficiency and flow characteristics of slurry transport. To solve this problem, a numerical method which couples the computational fluid dynamics (CFD) and the discrete element method (DEM) is established in this study. Using the coupled CFD-DEM, the internal flow structure for spherical, square platens and line-shaped coarse particles is studied, and the working conditions under which clogging of non-spherical particles occurs are explored. The flow states of different shaped particles at velocities of 2, 4.1 and 8 ms-1 are qualitatively analyzed in a horizontal pipeline system within the diameter of 100 mm, and quantitative analyses of the concentration distribution in different flow regimes are performed. The study describes the particle flow characteristics under clogging conditions based on the flow regime transition and concentration distribution. Abnormal transport is analyzed using qualitative and quantitative indications. In addition, along with the particle force and robustness of transport, the conditions for stable transport are discussed.