Modeling Issues in CFD Simulation of Brown Coal Combustion in a Utility Furnace

Abstract

This paper describes the mathematical formulation and modelling issues of a computational fluid dynamics (CFD) model of a 375 MW utility furnace. This tangentially-fired furnace is fuelled by high moisture content brown coal from coal mines at Latrobe Valley in Victoria, Australia. The influences of different turbulence models, particle dispersion, and radiation models on the CFD prediction are investigated. Two turbulence models, standard k-e model and Shear-Stress Transport (SST) model, provide similar predictions that are in good agreement with the plant data. The effect of particle dispersion on the prediction is found to be insignificant for this high-volatile brown coal. The predicted wall incident radiation flux based on two radiation models, namely, discrete transfer (DT) model and P-1 model are compared against power plant measurements. The comparison reveals that the DT model provides good prediction of the radiation profiles, while the P-1 model considerably under-predicts the wall incident radiation flux.