Abstract:

To prevent safety accidents such as bursting and leakage caused by wear in mine filling pipelines, CFD-DEM was employed to investigate the wear characteristics of filling slurries on pipelines. An L-shaped pipeline and a solid-liquid two-phase flow model were constructed to conduct numerical simulation experiments. Particle size (0.001-0.1 mm), slurry solid volume fraction (60%-80%), and slurry flow velocity (2-6 m/s) were used as variable parameters to explore the maximum wear rate of the pipeline under different conditions. The results indicate that both particle size and solid volume fraction exhibit a nonlinear relationship with the maximum wear rate. At a particle size of 0.1 mm, the maximum wear rate is 13.4 × 10^-5 kg/m². There is a critical solid volume fraction of 70%, at which the maximum wear rate was 7.15 × 10^-5 kg/m²; beyond this value, the wear rate tended to stabilize. The slurry flow velocity shows a linear relationship with the maximum wear rate; at a flow velocity of 7 m/s, the maximum wear rate is 8.25 × 10^-6 kg/m². The influence of each parameter on pipeline wear was ranked as follows: particle size > solid volume fraction > slurry flow velocity. The interaction between particle size and solid volume fraction has the most significant impact, followed by the interaction between solid volume fraction and slurry flow velocity, while the interaction between particle size and slurry flow velocity had the least effect.

Key words: computational fluid dynamics(CFD)-discrete element method (DEM), mines, backfill slurry, pipeline wear, slurry flow velocity, particle size, solid volume fraction