International Scientific Journal


In the present study, propane/oxygen and natural gas/oxygen diffusion flames within laminar regime have been investigated experimentally to determine the effects of oxidant preheating and diluting. This research has been divided into two parts. At first, effect of oxygen dilution with nitrogen and carbon dioxide gases has been investigated. In this section, stability and flame configuration variations are studied. Furthermore, it is inferred that combustion of natural gas and propane with pure oxygen can increase flame stability against increasing the fuel jet velocities through increasing burning velocity of the flame as compared with the combustion of natural gas or propane with normal air. In the other part, oxidant stream preheating up to 480 K and contemporaneous diluting with nitrogen or carbon dioxide are investigated and results are compared with non-preheating tests. Preheating causes more flame stability with respect to dilution process. Also, Due to combustion products temperature rise and also reduction in ignition delay time in preheating, these flames are more stable and also visually more luminous in comparison with normal temperature flames.
PAPER REVISED: 2011-06-25
PAPER ACCEPTED: 2011-09-02
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THERMAL SCIENCE YEAR 2012, VOLUME 16, ISSUE Issue 4, PAGES [1043 - 1053]
  1. Glassman, I., Combustion, Academic Press, 1997
  2. Ruan, J., et al, Effects of diluents on structure and stability of axisymmetric lifted laminar diffusion flames, Third Asian-Pacific Combustion Conference, Seoul, Korea, June 2001
  3. Juddoo, M., Masri, A.R., Bilger, R.W., The effects of oxygen enrichment on the structure of laminar diffusion flames of methane, 6th Asian-Pacific Combustion Conference, Nagoya, Japan, May 2007
  4. Ghosal, S., Vervish, L., Stability diagram for lift-off and blowout of a round jet laminar diffusion flame, Combustion and Flame, 123 (2001), pp. 646-655
  5. Usowicz, J.E., An experimental study of flame lengths and emissions of fully-modulated diffusion flames, Msc Thesis in Mechanical Engineering, Worcester Polytechnic Institute, 2001
  6. Sullivan, N., et al, Ammonia conversion and NOx formation in laminar coflowing nonpremixed methane-air flames, Combustion and Flame, 131 (2002), pp. 285-295
  7. Moore, J.D., Risha, G.A., Kuo, K.K., Effect of initial gaseous reactant temperature on fuel-rich coaxial diffusion flame stability, Eastern States Section of the Combustion Institute Technical Meeting, Pennsylvania State University, October 2003
  8. Ghaderi Yeganeh, M., Effects of preheated combustion air on laminar coflow diffusion flames under normal and microgravity conditions, Ph. D. Thesis in Mechanical Engineering, Maryland University, 2005
  9. Gupta, A., Flame characteristics and challenges with high temperature air combustion, Proceedings of 2000 International Joint Power Generation Conference, Florida, United States of America, July 2000
  10. Christo, F.C., Dally, B.B., Modeling turbulent reacting jets issuing into a hot and diluted coflow, Combustion and Flame, 142 (2005), pp. 117-129
  11. Medwell, P.R., Kalt, A.M., Dally, B.B., Simultaneous imaging of OH , formaldehyde, and temperature of turbulent nonpremixed jet flames in a heated and diluted coflow, Combustion and Flame, 148 (2006), pp. 48-61
  12. Kumar, P., Mishra, D.P., Experimental investigating of laminar LPG- H2 jet diffusion flame, International Journal of Hydrogen Energy, 33 (2008), pp. 225-231
  13. K.K. Kuo, Principles of Combustion, John Wiley & Sons Press, 1986
  14. Baukal, C.E., Oxygen-Enhanced Combustion, CRC Press, 1998
  15. Hasegawa, T., Katsuki, M., The science and technology of combustion in highly preheated air, Twenty-seventh symposium international on combustion, (1998), pp. 3135-3146
  16. Borman, G.L., Ragland, K.W., Combustion Engineering, McGraw-Hill, Singapore, 1998

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