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Show INTRODUCTION Pulverized coal (PC) is extensively used in utility and industrial boilers. The need to design more efficient combustion devices is quite clear with rising costs and increasing demand for energy. The existing technology base for designing utility and industrial boilers is primarily empirical and cannot be logically extended to study various effects (e.g., fuels, burner position and orientation, and boiler geometry) on system performance. Therefore, the technology base for PC combustion must be expanded if we are to better understand the complex combustion processes. One such way to understand these fundamental aspects of furnace performance is through the application of computational methods. Computational methods in fluid flow and heat transfer have been advanced to the point that such methods are being applied to the simulation of complex, yet practical combustion systems. The simulation of a pulverized-fuel combustion system involves modeling a number of complex, simultaneous, interdependent processes. The model must account for fluid flow, turbulence, particle transport, combustion, and radiation heat transfer. Gas fired processes have been modeled with reasonable success by a number of investigators (Gosman, et al., (1969), Abou Ellail, et al., (1978), Mitchell, et al., (1980)). However pulverized-coal combustion has received less attention, partly because of the significant increase in complexity required to model the coal particles and their effect on the gas phase. The first such computational method for pulverized coal (PC) was due to Gibson and Morgan (1970). Recent studies by Richter and Fleischhans (1976), Lockwood, et al., (1980), Smith and Smoot (1982), and Fiveland, et al., (1984), have employed more sophisticated techniques and demonstrated promise in predicting PC combustor performance. In this paper a three dimensional furnace model (FURMO) is presented to assess pulverized-coal combustion and heat transfer in practical furnace geometries. Results are presented for a utility size furnace and show promise of assisting engineers and designers in the optimization and design of combustion equipment. -2- |