Numerical investigation into the fragmentation efficiency of one coal prism in a roller pulveriser: Homogeneous approach

• A numerical approach is developed to determine geometric properties of fragments.
• A coupled SPH–FEM approach is verified and then applied for modelling.
• The early-stage breakage modes of a coal prism in a pulveriser is investigated.
• Factors influencing the fragmentation efficiency of a single coal prism are studied.

The aim of this paper is to numerically model the rolling compression induced breakage process of a single coal prism in a roller pulveriser and to quantify the resultant fragmentation efficiency. A coupling approach of the finite element method (FEM) and the smoothed particle hydrodynamics (SPH) method is adopted to examine the complete deformation and progressive fragmentation process involved. A coupled damage-plastic material model is used to simulate the complex deformation and failure behaviour of coal materials. In order to quantify the geometric properties of main fragments by the rolling compression, a numerical approach is developed based on the union-find algorithm. Parametric studies have been conducted considering various factors, including the geometric factors of prismatic coal specimens and the rotating velocity of the rigid roller. Typical modelling results are provided and the fragmentation efficiency is examined and discussed with respect to the corresponding factors.