Effects of Air Temperature on Combustion Characteristics of LPG Diffusion Flame

Abstract:

In the present study, the combustion characteristics of LPG gaseous fuel diffusion flame at elevated air temperatures were experimentally investigated. An experimental test rig was manufactured to examine a wide range of operating conditions. The investigated parameters are the air temperatures of 300, 350, 400, 450, and 500 K with constant percentage of nitrogen addition in combustion air stream of 5 % to give low oxygen concentration of 18.3 % by mass at constant air swirl number, air to fuel mass ratio, and thermal load of 1.5, 30, and 23 kW, respectively. The gaseous combustion characteristics were represented as axial and radial temperatures distributions, temperatures gradient, visible flame length and species concentrations. The results indicated that as the air temperature increased, the chemical reaction rate increased and flame volume decreased, the combustion time reduced leading to a reduction in flame length. The NO concentration reaches its maximum values near the location of the maximum centerline axial temperature. Increasing the combustion air temperature by 200 K, the NO consequently O₂ concentrations are increased by about % 355 and 20 % respectively, while CO₂ and CO concentrations are decreased by about % 21 and 99 % respectively, at the combustor end.

• Periodical: Materials Science Forum (Volume 1008)
• Pages: 128-138
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.1008.128
• Online since: August 2020
• Authors: Ahmed M. Salman*, Ibrahim A. Ibrahim, Hamada M. Gad, Tharwat M. Farag
• Keywords: Combustion Air Temperature, Infrared Gas Analyzer, Low Oxygen Concentration, NOx Emission

References

[1] Zevenhoven, R., and Kilpinen, P., Control of Pollutants in Flue Gases and Fuel Gases,, Helsinki University of Technology, course ENE-47.153, (2004).

[2] Miller, J.A. and Bowman, C.T., Mechanism and Modelling of Nitrogen Chemistry in Combustion,, Prog. in Energy and Comb. Sci., 15, 287, (1989).

[3] Svoboda, K., Čermák, J. and Trnka, O., Chemistry and Emissions of Nitrogen Oxides (NO, NO2, N2O) in Combustion of Solid Fuels,, Institute of Chemical Process Fundamentals, Academy of Sciences of the Czech Republic (2000).

DOI: 10.1002/chin.200038263

[4] Zeldovich, Y. B., The Oxidation of Nitrogen in Combustion Explosions,, Acla Physicochimica, U.S.S.R. 21, p.577–628, (1946).

[5] Fenimore, C. P., Proc. Combust. Inst. 13, 373, (1971).

[6] Tanaka, R., New progress of energy saving technology toward the 21st century; Frontier of combustion & heat transfer technology; Proceedings of 11th IFRF Members Conference; 10 - 12th May, Netherlands, (1995).

[7] Hasegawa, T., and Tanaka, R., High temperature Air combustion-Revolution in combustion Technology,, JSME International Journal Series B, Vol.4, No.4, pp.1079-1084, (1998).

DOI: 10.1299/jsmeb.41.1079

[8] Takagi, T., XU, Z., and Komiyama, M., Preferential Diffusion Effects on the Temperature in Usual and Inverse Diffusion Flames,, Combustion & Flame 106, pp.252-260, (1996).

DOI: 10.1016/0010-2180(95)00255-3

[9] Ishiguro T., Tsuge S., Furuhata K., Kitagawa N., Arai T., Hasegawa R., Tanaka and A. K. Gupta, Homogenization and stabilization during combustion of hydrocarbons with preheated air,, 27th symposium (International) combustion, pp.3205-3213, (1998).

DOI: 10.1016/s0082-0784(98)80184-7

[10] Reddy, S. S., Effect of Preheated Air on the Structure of Coaxial Jet Diffusion Flame,. International Archive of Applied Sciences & Technology, Vol.4, pp.70-75, (2013).

[11] Ghaderi Yeganeh, M., Effects of Preheated Combustion Air on Laminar Coflow Diffusion Flames Under Normal and Microgravity Conditions,, Ph. D. Thesis, Maryland University, College Park, Md., USA, (2005).

[12] Gupta, A., Flame Characteristics and Challenges with High Temperature Air Combustion,, Proceedings, 2000 International Joint Power Generation Conference, Miami Beach, Fla., USA, (2000).

[13] Christo, F. C. and Dally, B. B., Modeling Turbulent Reacting Jets Issuing into a Hot and Diluted Coflow,, Combustion and Flame, 142, pp.117-129, (2005).

DOI: 10.1016/j.combustflame.2005.03.002

[14] Medwell, P. R., Kalt, A. M. and 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, pp.48-61, (2006).

DOI: 10.1016/j.combustflame.2006.10.002

[15] Mishra, D. P., and Kumar, P. Experimental Investigating of Laminar LPG- H2 Jet Diffusion Flame with Preheated Reactants,, Fuel, 87, p.3091–3095, (2008).

DOI: 10.1016/j.fuel.2008.02.022

[16] Kashir, B., Tabejamaat, S. and Mohammadi, M.B, Experimental Study on‏ Propane/Oxygen and Natural Gas/Oxygen Laminar Diffusion‏ Flames in Diluting and Preheating Conditions,, Thermal Science, Vol. 16, pp.1043-1053, (2012).

DOI: 10.2298/tsci110524122k

[17] Kim, W. B., Chung, D. H., Yang, J. B., and Noh, D. S., An Experimental Study on High Temperature and Low Oxygen Air Combustion,, Journal of Thermal Science Vol. 9, No.2, p.169–175, (2000).

DOI: 10.1007/s11630-000-0013-2

[18] Mortberg, M., Study of gas fuel jet burning in low oxygen content and high temperature oxidizer,, Doctoral Dissertation, Royal Institute of Technology, Division of Energy and Furnace Technology, Stockholm, Sweden, (2005).

[19] Amer, A. A., Gad, H. M., Ibrahem, I. A., Abdel-Mageed S. I., and Farag, T. M., Experimental Study of LPG Diffusion Flame at Elevated Preheated Air Temperatures,, World Academy of Science, Engineering and Technology, International Journal of Mechanical, Aerospace, Industrial, Mechatronic and Manufacturing Engineering Vol. 9, No.8, (2015).

[20] Husain, A. K., Mashkoor, M. A. and Khalaf, F. A., Experimental Investigation of Preheated Air Effects with Multiline of Fuel Injection (LPG) on a Tubular Combustor of Micro Gas turbine,, Journal of University of Babylon for Engineering Sciences, Vol. 26, No.9, (2018).

DOI: 10.29196/jubes.v26i7.1537

[21] Elbaz, A. M., Moneib, H. A., Shebil, K. M. and Roberts, W. L., Low NOx - LPG staged combustion double swirl flames,, Renewable Energy 138, pp.303-315, (2019).

DOI: 10.1016/j.renene.2019.01.070