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Show 5. CONCLUSIONS The mathematical 3-dimensional coal combustion model which has a capability predicting NO concentration in a utility boiler furnace has been developed. The model solves the time averaged conservation equations for the species that are important in NO formation and reduction in fossil boilers using the eddydissipation combustion model. The flow field is solved by the SIMPLER algorithm and the turbulence is calculated by the standard k-E model. The radiation is handled by the six-flux model. To verify the model, it is applied to the heat transfer, fluid flow, and pollutant formation characteristics prediction of the trial operation condi tion for the 1000MWe utility boiler and it is demonstrated that the model has a capability to show us a qualitatively reasonable result. REFERENCES 1. S.V. Patankar, Numerical Heat Transfer and Fluid Flow, Hemisphere, 1980. 2. C.T. Crowe, M.P. Sharma and D.E. Stock, The Particle Source-InCell( PSI-CELL) Model for Gas-Droplet Flows, ASME Journal of Fluids Engineering, Vol.99, p.325, 1977. 3. E.K. Melville and N.C. Bray, A Model for Two-Phase Turbulent Jet, International Journal of Heat and Mass Transfer, Vol.22, p.647,1979. 4. B.F. Magnussen and B.H. Hjertager, On Mathematical Modeling of Turbulent Combustion with Special Emphasis on Soot Formation and Combustion, 16th Symposium (International) on Combustion, The Combustion Institute, Pittsburgh, PA, p.719, 1976. 5. H. Kobayashi, J.B. Howard and A.F. Sarofim, Coal Devolatilization at High Temperatures, 16th Symposium (International) on Combustion, The Combustion Institute, Pittsburgh, PA, p.411, 1976. 6. L.D. Smoot and P.J. Smith, Coal Combustion and Gasification, Plenum Press, 1985. 7. S.V. Patankar, A Calculation Procedure for Two-Dimensional Elliptic Situations, Numerical Heat Transfer, vol. 4, pp409-425, 1981. 8. S.V. Patankar and D.B. Spalding, A Computer Model for ThreeDimensional Flow in Furnaces, 14th Symposium (International) on Combustion, The Combustion Institute, Pittsburgh, PA, p.605, 1972. 9. W.A. Fiveland, R.A. Wessel and D.Eskinazi, Pollutant Model for Predicting Formation and Reduction of Nitric Oxides in ThreeDimensional, Pulverized-Fuel Fired Furnaces, 24th National Heat Transfer Conference and Exhibition, Pittsburgh, PA, August 9- 12, 1987 10. G.G. DeSoete, Overall reaction Rates of NO and N2 Formation from Fuel Nitrogen, 15th Symposium (international) on Combustion, The Combustion Institute, Pittsburgh, PA, p.1093, 1975. 8 |