Investigation of wear pattern in a complex coal pulveriser using CFD modelling

In this study, we have constructed a commercial-scale pulveriser and simulated motion of air and coal particles inside the pulveriser to investigate the effect of air passage on the wear pattern. Simulations were carried out using Eulerian-Lagrangian approach. The results indicated that the primary air entering into the pulveriser under the bowl via splitters, exited the pulveriser vanes to the left with the highest velocity. This validates the constructed model as the nozzle ring above the bowl has vanes that run clockwise making most of the primary air to exit the vanes to the left. Additional simulations with modified inlet duct geometry led to a possible solution for making the airflow distribution even at the base of the mill, which is expected to reduce the wear pattern. The results presented in the paper provides impetus for the modification of the airflow path using baffle splitters in the primary air duct, which could prove valuable to designers for the optimisation of airflow and the potential reduction of wear on the components within the coal pulveriser. (C) 2006 Elsevier B.V. All rights reserved.