Numerical Model for Predicting Performance of Three-Dimensional Pulverized-Fuel Fired Furnaces

A numerical furnace model (FURMO) was developed to model steady-state, three-dimensional pulverized-fuel combustion in practical furnace geometries. This model is based on a fundamental description of various interacting processes which occur during combustion: turbulent flow, heterogeneous and homogeneous chemical reaction, and heat transfer. The detailed analysis achieved by the method is useful for evaluating furnace performance and in the interpretation of laboratory, intermediate, and utility test data. In this paper, three-dimensional pulverized coal combustion is investigated for a 560 MW utility boiler. Numerical results for flow, heat transfer, and chemistry are presented. Contour maps are exhibited to describe these complex three-dimensional interactions. Model sensitivity is evaluated for changes in slag layer thickness, particle size distribution, and devolatilization and char oxidation rates.