Abstract
A large-eddy simulation of coal combustion on a pulverized coal combustion furnace with a complex swirl burner is performed and validated by comparing with the experiment in this study. Unstructured grid system is employed to apply LES to the practical complex geometry burner. The motion of coal particles is calculated by the Lagrangian method with the parcel model. The direct closure SSFRRM (Scale similarity filtered reaction rate model) is used as a turbulent combustion model. The results show that a recirculation flow is formed in the downstream central region of the burner and its region varies dynamically due to the turbulent mixing with the axial direction flows. Comparisons of the axial distributions of time-averaged gaseous temperature and oxygen concentration shows in general good agreement with the experiment results, although the distribution of NO concentration which is relatively minor to the major species in the combustion is not in agreement with the experiment result very much. It is confirmed that the basic combustion characteristics can be captured and the capability of the LES of coal combustion field is well demonstrated in this study.
