A numerical assessment of different geometries for reducing elbow erosion during pneumatic conveying

Abstract

This paper investigates wear characteristics in a dilute phase pneumatic conveying pipe system using a Euler-Lagrange method. Simulations couple computational fluid dynamics (CFD) with the discrete element method (DEM) to analyze three different bend geometries, including two erosion-reducing designs and a standard bend, all with an effective bend radius to pipe diameter ratio (R/D) of 1.5. SiO2 particles, 1 mm in diameter, are conveyed at gas velocities of 15 to 30 m/s and mass loadings of 1 to 4 kgparticle/kggas. The CFD-DEM predictions were validated against experimental data, showing good agreement in erosion distribution. The study evaluates erosion rates, pressure drops, and particle stressing for the three bends. Results suggest that certain bend designs significantly reduce erosion while slightly increasing pressure drop, although reduced particle-wall erosion may increase the overall particle stressing. The obtained results provide guidance on selecting an appropriate bend design and for potential geometry optimizations.