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http://dx.doi.org/10.4491/KSEE.2013.35.12.967

A Study on the Exhaust Gas Recirculation in a MILD Combustion Furnace by Using the Coanda Nozzle Effect  

Ha, Ji Soo (Environmental Science Department, Keimyung University)
Shim, Sung Hoon (Korea Institute of Machinery & Materials)
Publication Information
Journal of Korean Society of Environmental Engineers / v.35, no.12, 2013 , pp. 967-972 More about this Journal
Abstract
A MILD (Moderate and Intense Low oxygen Dilution) combustion, which is effective in the reduction of NOx, is considerably affected by the recirculation flow rate of hot exhaust gas to the combustion furnace. The present study used the MILD combustor, which has coaxial cylindrical tube. The outside tube of the MILD combustor corresponds to the exhaust gas passage and the inner side tube is the furnace passage. A numerical analysis was accomplished to elucidate the characteristics of exhaust gas entrainment toward the inner furnace with the changes of coanda nozzle geometrical parameters, nozzle passage gap length, nozzle passage length, nozzle angle and expansion length. The optimal configuration of coanda nozzle for the best entrainment flow rate was gap length, 0.5 mm, expansion angle, 4o and expansion length, 146 mm. The nozzle passage length was irrelevant to the exhaust gas entrainement.
Keywords
MILD Combustion; Coanda Nozzle; Nozzle Passage Gap; Nozzle Passage Length; Nozzle Angle; Nozzle Expansion Length; Flow Rate Ratio;
Citations & Related Records
Times Cited By KSCI : 3  (Citation Analysis)
연도 인용수 순위
1 Ha, J. S., Kim T. K. and Shim, S. H., "A numerical study of the air fuel ratio effect on the combustion characteristics in a MILD combustor," Kor. Soc. Environ. Eng., 32(6), 587-592(2010).   과학기술학회마을
2 Shim S. H. and Ha, J. S., "A study on the flow entrainment characteristics of a coaxial nozzle used in a MILD combustor with the change of nozzle position and flow condition," Kor. Soc. Environ. Eng., 34(2), 103-108(2012).   과학기술학회마을   DOI   ScienceOn
3 Launder, B. E. and Spalding, D. B., "The Numerical Computation of Turbulent Flows. Computer methods in Applied Mechanics and Engineering," pp. 269-289(1974).
4 Magnussen, B. F. and Hjertager, B. H., "On mathematical model of turbulent combustion with special emphasis on soot formation and combustion," In 16th Symp. on Combustion, 1976.
5 Patankar, S. V., "Numerical Heat Transfer and Fluid Flow," pp. 126-131(1980).
6 Plessing, T., Peters, N. and Wunning, J. G., "Laseroptical investigation of highly preheated combustion with strong exhaust gas recirculation," 27 Symp (Int) Combustion, pp. 3197-3204, 1998.
7 Kim, T. K., Shim, S. H., Chang, H. S. and Ha, J. S., "A numerical study of the combustion characteristics in a MILD combustor with the change of the fuel and air nozzle position and air mass flow rate," Kor. Soc. Environ. Eng., 33(5), 325-331(2011).   과학기술학회마을   DOI   ScienceOn
8 Liu, F., Becker, H. A. and Bindar, Y. "A comparative modeling in gas-fired furnaces using the Simple Grey Gas and the Weighted-Sum-of-Grey-Gases Models," Int. J. Heat Mass Transfer, 41, 3357-3371(1998).   DOI   ScienceOn
9 Katsuki, M. and Hasegawa, T., "The science of technology of combustion in highly preheated air," 27 Symp (Int) Combustion, pp. 3135-3146(1998).
10 Wuuning, J. A. and Wunning, J. G., "Flameless oxidation to reduce thermal NO-formation," Prog. Energy Combust. Sci., 23, 81-97(1997).
11 Cavaliere, A., Joannon, De M. and Ragucci, R. "Mild combustion of high temperature reactants," 2nd International Symposium on High Temperature Air Combustion, 1999.
12 Frazan, H., Maringo, G. J., Riggs, J. D., Yagiela, A. S. and Newell, R. J., "Reburning with Powder River Basin Coal to Achieve $SO_2$ an $NO_x$ Compliance," Proc. of the Power-Gen Sixth International Conference, Dallas, pp. 175-187, 1993.