Research on the Wear Characteristics of a Bend Pipe with a Bump Based on the Coupled CFD-DEM

Abstract

In the process of hydraulic lifting of solid mineral particles on the seabed, the two-phase flow in the pipeline causes wall wear, which reduces the reliability of the hydraulic lifting system. In this research, based on the coupled computational fluid dynamics (CFD) and discrete element method (DEM), the numerical simulation of large particle solid–liquid two-phase flow and wall wear in a bend pipe with different wall shapes was conducted to provide solutions for reducing wall wear. By adding bumps to the bend pipe wall to change the shape of its inner wall, under the working conditions of particle concentrations of 1–10% and particle sizes of 1–3 mm, wear experiments and calculations for the bend pipe with bumps at different positions were performed. With comparative analysis, it was found that the location of the bump in the bend pipe had an important influence on the maximum wear rate. When the bump was located near the location where the particles collided with the prototype bend pipe for the first time, the maximum wear rate decreased the most significantly. The particle mass flow rate will also affect the wear reduction effect of the bump on the bend pipe wall.