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Show IFRF Doc. No. K 70/a/12 August 1989 - 9 - Mathematical Modelling of Pulverised Coal Flames 6. CONCLUSIONS A mathematical model of swirled pulverised coal flame has been developed. Predictions of two pulverised coal flames are validated against in-flame measurements. The computed flames were of a high volatile coal. The model predicts flame properties in the near burner zone and in the furnace. The emphasis was put on the region in which the NOx formation and reduction mechanisms occur: inside the burner quarl and in the flame region one quarl diameter downstream of the furnace front wall. The model predicted accurately the measured values of temperature, oxygen, carbon dioxide in such a close vicinity of the burner. The carbon monoxide predictions were only in qualitative agreement with measurements. The measured differences in the near burner zone properties of the considered flames were properly highlighted in the predictions. ACKNOWLEDGEMENT The authors gratefully acknowledge the financial support of the lEA Coal Combustion Science Programme, Annex 2, sponsored by Canada, the Federal Republic of Gernamy and the Netherlands. REFERENCES [ 1] F C LOCKWOOD and T MAHMUD The prediction of swirl burner pulverised coal flames. 22nd Symp on Comb, The Comb Inst, 1988. [ 2] K GORNER and W ZINSER Prediction of three dimensional flows in furnace and comparison with experiments. Turbulent Reactive flows, AMD-Vol 81, 1986. [ 3] J S TRUELOVE and R G WILLIAMS Coal combustion models for flame scaling. 22nd Symp on Comb, The Comb Inst, 1988. [ 4] L L BREWSTER, L L BAXTER and L D SMOOT Energy and Fuels, Vol. 2, No 4, 1988. utility boiler Calculation of [ 5] R WEBER, F BOYSAN, J SWITHENBANK and P A ROBERTS Computations of near field aerodynamics of swirling expanding flows. 21st Symp on Comb, The Comb Inst, 1986. [ 6] B M VISSER, F BOYSAN and R WEBER Computations of isothermal swirling vortices in the near burner zone. IFRF IFRF Doc. No. F 336/a/9, 1987. |