Hydrodynamic simulation of multi-sized high concentration slurry transport in pipelines

A steady-state three-dimensional multiphase hydrodynamic model based on the kinetic theory of granular flow is developed to investigate the distributions of solid concentration, flow velocity, granular pressure, and wall shear stress in multi-sized slurry (two particle sizes, dp = 0.125 mm and 0.44 mm, equal fraction by mass) transport by pipelines (D = 54.9 mm). The trends of the variation in transport properties with varying efflux particle concentrations (Cvf = 20%, 30%, 40%, and 50%) and flow velocities (v = 2, 3, 4, and 5 m/s) are studied, and the effects of other different-sized particles on characteristics are modeled. Simulation results agree well with the corresponding experimental results in literature. The simulation results show that coarse and fine particle phases have different characteristics in each operating condition. The degree of deviation of the characteristics of different-sized particles increases as solid concentration or mixture velocity decreases. Additionally, the distinct effects of near-wall lift force and particle-wall collision on the characteristics of different-sized particles in multi-sized slurry are observed. The results obtained in this work elucidate the characteristics of different-sized particles in multi-sized slurry and provide a solid foundation for studying the mesoscopic processes of slurry transport by pipelines.