THERMAL SCIENCE
International Scientific Journal
EXPERIMENTAL INVESTIGATION ON LIFT-OFF, BLOWOUT AND DROP-BACK IN PARTIALLY PREMIXED LPG OPEN FLAMES IN TUBULAR BURNER
ABSTRACT
The higher pollutant level in non premixed combustion and safety issues pertaining to premixed combustion can be counteracted by partially-premixed mode of combustion. The partially premixed flames (PPF) exhibit the benefits of both premixed and non premixed flames. PPF enhances complete combustion leading to reduced soot formation and hence lower emission. However, the equivalence ratio plays an important role in the stability of such flames. This paper reports the experimental investigation on the flame characteristics and stability of partially premixed LPG-air flames in tubular burner. The stability curve obtained for the base case without any secondary flow shows that the velocity at lift-off, drop-back and blowout increases with increasing equivalence ratio. In the presence of secondary co-flow air, the lift-off and blow off velocity decreases compared to base case indicating poor stability due to extensive flame stretch leading to aerodynamic quenching. The experimental results show that the velocity of flow at lift off, blow out and drop back are higher in the presence of secondary swirl air than the base case. Co-swirl air increases the stability due to better mixing at the flame base with increased residence time. Flame stability deteriorates with co-flow air as co-flow strains the flame boundary due to flame stretch.
KEYWORDS
PAPER SUBMITTED: 2021-11-26
PAPER REVISED: 2022-01-23
PAPER ACCEPTED: 2022-01-25
PUBLISHED ONLINE: 2022-03-05
THERMAL SCIENCE YEAR
2022, VOLUME
26, ISSUE
Issue 6, PAGES [4607 - 4615]
- Zeenathul Farida Gani, Behdad Moghtaderi, Terry F. Wall, Ignition Characteristics of Single Coal Particles in Air (O2/N2) and Oxy-Fuel (O2/CO2) Environments, Proceedings, 1st Oxyfuel Combustion Conference, Cottbus, Germany, 2009, Vol. 1.
- Zeenathul Farida Abdul Gani, Arun Pandian P., Modelling of coal combustion in a Drop Tube Furnace in Air and Oxy fuel Environment, Materials Today Proceedings, 47 (2021), 14, pp. 4431-4437
- Zeenathul Farida Abdul Gani et al., Experimental study on the stability and flame characteristics of LPG flames in O2/N2 and O2/CO2 environment, Materials Today Proceedings, 49 (2021), 5, pp. 2019-2024
- Zeenathul Farida Abdul Gani, Muthusaravanan N., Computational analysis on the stability and characteristics of partially premixed butane air open flames in tubular burner, Thermal Science, Article in press, https://doi.org/10.2298/TSCI210712320A
- Kalghatgi, G.T., Blow-out stability of gaseous jet diffusion flames Part II: effect of cross wind, Combustion Science and Technology, 26 (1981), 26, pp. 241–244. https://doi.org/10.1080/00102208108946965
- Pitts, W. M., Assessment of theories for the behavior and blowout of lifted turbulent jet diffusion flames, Proceedings of twenty second International Symposium on Combustion, 1988. pp. 803–16. https://doi.org/10.1016/S0082-0784(89)80090-6
- Hemmatian, B, et al., The significance of domino effect in chemical accidents, Journal of Loss Prevention in the Process Industries, 29 (2014), pp. 30–8. https://doi.org/10.1016/j.jlp.2014.01.003
- Lewis, B., von Elbe, G., Combustion, Flames and Explosions of Gases, 2nd Edition, Academic, New York, 1961. eBook ISBN: 9780323138024
- Vanquickenborne, L, van Tiggelen, A., The stabilization mechanism of lifted diffusion flames, Combustion and Flame, 10 ( 1966), pp. 59–69. https://doi.org/10.1016/0010-2180(66)90028-9
- Miake-Lye, R. C, Hammer, J. A., Lifted turbulent jet flames: a stability criterion based on the jet large-scale structure, Proceedings of twenty second International Symposium on Combustion, 1988, pp. 817–24. https://doi.org/10.1016/S0082-0784(89)80091-8
- Rokke, N. A, Hustad, J. E, Sonju, O. K., A study of partially premixed unconfined propane flames, Combustion and Flame, 97 (1994), pp. 88–106. https://doi.org/10.1016/0010-2180(94)90118-X
- Karlovitz, B., et al., Studies on turbulent flames, Fourth Symposium (International) on Combustion, Williams and Wilkins, Baltimore, 1953, pp. 613.
- Gaydon, A. G., Wolfhard, H. G., Flames, Their Structure Radiation and Temperature, 4th Edition, Chapman and Hall, London, 1979. https://doi.org/10.1002/cite.330510724
- Eickhoff, H., Lenze, B., Leuckel, W., Experimental investigations on the stabilization mechanism of jet diffusion flames, Twentieth Symposium (International) on Combustion, The Combustion Institute, Pittsburgh, 1984, pp. 311-318. https://doi.org/10.1016/S0082-0784(85)80516-6
- Peters, N., Williams, F. A., Lift-off Characteristics of turbulent jet diffusion flames, American Institute of Aeronautics and Astronautics, Nevada, Vol. 21, 1983, pp. 423-429. https://doi.org/10.2514/6.1982-111
- Burgess, C. P., Lawn, C. J., The premixture model of turbulent burning to describe lifted jet flames, Combustion and Flame, 119 (1999), pp. 95-108. https://doi.org/10.1016/S0010-2180(99)00037-1
- Kalyan Raja, R., Shet, U. S. P., Stability of partially premixed laminar flames in cross-flow, Eighteenth National Conference on IC Engines and Combustion, College of Engineering, Thiruvananthapuram, India, December 17-19, 2003, pp. 413-419
- Wang, Q., et al., Blow-out limits of nonpremixed turbulent jet flames in a cross flow at atmospheric and sub-atmospheric pressures, Combustion and Flame, 162 (2015), 10, pp. 3562–3568. https://doi.org/10.1016/j.combustflame.2015.06.012
- Moore, N. J., Kribs, J., Lyons, K. M., Investigation of Jet-Flame Blowout with Lean-Limit onsiderations, Flow, Turbulence and Combustion, 87 (2011), 4, pp. 525–536. https://doi.org/10.1007/s10494-011-9334-3
- Chen, Z., Ruan, S., Swaminathan, N., Simulation of turbulent lifted methane jet flames: Effects of air-dilution and transient flame propagation, Combustion and Flame, 162 (2015), 3, pp. 703–716. https://doi.org/10.1016/j.combustflame.2014.09.010
- Quattrocchi, S., Aggarwal, S. K., Katta, V. R., Liftoff and blowout characteristics of laminar syngas nonpremixed flames. International Journal of Hydrogen Energy, 43 (2018), 12, pp. 6421–6433. https://doi.org/10.1016/j.ijhydene.2018.01.194
- Palacios, A., et al., Analysis of experimental flame shapes and blowout velocities of partially-premixed methane-air jet flames, Fuel, 269 (2020), 117430-117435. https://doi.org/10.1016/j.fuel.2020.117430
- Rao, G.V.S.N., Sriramulu, V., Some characteristics of flames in swirling streams, Thermochimica Acta, 16 (1976), pp. 388-394. https://doi.org/10.1016/0040-6031(76)80032-9
- Irvin Glassmann and Richard A Yetter, Combustion, Fouth Edition, Elsevier Publication, ISBN - 978-0-12-407913-7
- Wu, C. Y., et al., The blowout mechanism of turbulent jet diffusion flames, Combustion and Flame, 145, (2006), 3, pp. 481–494. https://doi.org/10.1016/j.combustflame.2006.01.004
- Dahm, W. J. A., Dibble, R. W., Co-flowing turbulent jet diffusion flame blowout, Proceedings of the 22nd International Symposium on Combustion, pp. 801–808, The Combustion Institute, Seattle, Wash, USA, August 1988. https://doi.org/10.1016/S0082-0784(89)80089-X
- Han, D., Mungal, M. G., Observations on the transition from flame liftoff to flame blowout, Proceedings of the 28th International Symposium on Combustion, pp. 537–543, The Combustion Institute, Edinburgh, UK, July-August 2000. https://doi.org/10.1016/S0082-0784(00)80253-2