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Research Papers: Fuel Combustion

Turbulent Flame Characteristics of Oxycoal MILD Combustion

[+] Author and Article Information
Ruochen Liu, Enke An

Department of Mechanical and
Energy Engineering,
Tongji University,
Shanghai 201804, China

1Corresponding author.

Contributed by the Advanced Energy Systems Division of ASME for publication in the JOURNAL OF ENERGY RESOURCES TECHNOLOGY. Manuscript received September 8, 2016; final manuscript received June 14, 2017; published online July 17, 2017. Assoc. Editor: Reza Sheikhi.

J. Energy Resour. Technol 139(6), 062206 (Jul 17, 2017) (8 pages) Paper No: JERT-16-1362; doi: 10.1115/1.4037190 History: Received September 08, 2016; Revised June 14, 2017

Oxycoal combustion was numerically simulated in a lab-scale cylindrical furnace (Φ200 mm × 2 m) with high-velocity oxygen jets. The mesoscopic characteristics of turbulent flame behavior such as nondimensional numbers ReT, Ka, and Da were calculated under different jet positions and jet spacing. The results show that for coflow burners, large spacing (L = 75 mm) is not favored due to poor radial mixing and the restriction of wall; except L = 75 mm, as jet spacing increases, the oxidizer flow could be internally diluted to a lower concentration and preheated to a higher temperature, at least 1000 K; for L = 60 mm conditions, the maximum temperature increase is lower than the ignition temperature (437 °C), they are, namely, oxycoal moderate or intense low oxygen dilution (MILD) combustion. For MILD conditions, the mesoscopic parameters of the flame front where temperature gradient is the largest locate in the distributed regime corresponding to l/lF > 1, ReT > 1, Kaδ > 1, and Da < 1, the global regime is depicted as 1 < l/lF < 4, 60 < ReT < 150, 50 < Ka < 500, and Da < 1; for flaming conditions, the regime is depicted as 1 < l/lF < 6, 40 < ReT < 110, 10 < Ka < 800, and Da < 1.

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References

Tola, V. , Cau, G. , Ferrara, F. , and Pettinau, A. , 2016, “ CO2 Emissions Reduction From Coal-Fired Power Generation: A Techno-Economic Comparison,” ASME J. Energy Resour. Technol., 138(6), p. 061602. [CrossRef]
Gupta, A. K. , Bolz, S. , and Hasegawa, T. , 1999, “ Effect of Air Preheat Temperature and Oxygen Concentration on Flame Structure and Emission,” ASME J. Energy Resour. Technol., 121(3), pp. 209–216. [CrossRef]
Ibrahim, A. S. , and Ahmed, S. F. , 2015, “ Measurements of Laminar Flame Speeds of Alternative Gaseous Fuel Mixtures,” ASME J. Energy Resour. Technol., 137(3), p. 322091. [CrossRef]
Krishnamurthy, N. , Paul, P. J. , and Blasiak, W. , 2009, “ Studies on Low-Intensity Oxy-Fuel Burner,” Proc. Combust. Inst., 32(2), pp. 3139–3146. [CrossRef]
Mi, J. , Li, P. , Dally, B. B. , and Craig, R. A. , 2009, “ Importance of Initial Momentum Rate and Air-Fuel Premixing on Moderate or Intense Low Oxygen Dilution (MILD) Combustion in a Recuperative Furnace,” Energy Fuels, 23(11), pp. 5349–5356. [CrossRef]
Veríssimo, A. S. , Rocha, A. M. A. , and Costa, M. , 2013, “ Importance of the Inlet Air Velocity on the Establishment of Flameless Combustion in a Laboratory Combustor,” Exp. Therm. Fluid Sci., 44, pp. 75–81. [CrossRef]
Deng, X. , Xiong, Y. , and Yin, H. , and Gao, Q. , 2016, “ Numerical Study of the Effect of Nozzle Configurations on Characteristics of MILD Combustion for Gas Turbine Application,” ASME J. Energy Resour. Technol., 138(4), p. 422121. [CrossRef]
Sanminathan, N. , and Bray, K. N. C. , 2011, Turbulent Premixed Flames, Cambridge University Press, Cambridge, UK. [CrossRef]
Peters, N. , 2004, Turbulent Combustion, Cambridge University Press, Cambridge, UK.
Simth, T. F. , Shen, Z. F. , and Friedman, J. N. , 1982, “ Evaluation of Coefficients for the Weighted Sum of Gray Gases Model,” ASME J. Heat Transfer, 104(4), pp. 602–608. [CrossRef]
Johansson, R. , Andersson, K. , Leckner, B. , and Thunman, H. , 2010, “ Models for Gaseous Radiative Heat Transfer Applied to Oxy-Fuel Conditions in Boilers,” Int. J. Heat Mass Transfer, 53(1–3), pp. 220–230. [CrossRef]
Chungen, Y. , 2013, “ Refined Weighted Sum of Gray Gases Model for Air-Fuel Combustion and Its Impacts,” Energy Fuels, 27(10), pp. 6287–6294. [CrossRef]
Qi, Y. , 2011, “ Numerical Simulation of Non-Grey Radiation Characteristics and Heat Transfer in Oxy-Fuel Combustion,” Master thesis, Hauzhong University of Science and Technology, Wuhan, China.
Liu, R. , An, E. , Liu, Z. , and Yuan, Y. , 2016, “ Radiation Characteristics of Oxy-Fuel Combustion Flue Gas,” J. Combust. Sci. Technol., 22(1), pp. 84–90. http://en.cnki.com.cn/Article_en/CJFDTotal-RSKX201601014.htm
Schaffel, N. , Mancini, M. , Szle, K. A. , and Weber, R. , 2009, “ Mathematical Modeling of MILD Combustion of Pulverized Coal,” Combust. Flame, 156(9), pp. 1771–1784. [CrossRef]
Cavaliere, A. , and Joannon, M. , 2004, “ MILD Combustion,” Prog. Energy Combust. Sci., 30(4), pp. 329–366. [CrossRef]
Liu, R. , An, E. , Wu, K. , and Liu, Z. , 2015, “ Numerical Simulation of Oxy-Coal MILD Combustion With High-Velocity Oxygen Jets,” J. Energy Inst., 90(1), pp. 30–43. [CrossRef]

Figures

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Fig. 1

The sketch of the lab-scale furnace

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Fig. 2

The total gas emissivity calculated through refined WSGGM and SWBCK

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Fig. 3

The velocity fields of IFRF coal MILD combustion

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Fig. 4

The temperature fields of IFRF coal MILD combustion

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Fig. 5

Mathematical schematic of preheating and mixing zone

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Fig. 6

The contour of flame front under IFRF coal MILD combustion (unit: m)

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Fig. 7

The mesoscopic characteristic parameters of flame front in the regime

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Fig. 8

The distribution of Ka on the X–Z section

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Fig. 9

The distribution of Da on the X–Z section

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Fig. 10

The distribution of l/lF on the X–Z section

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Fig. 11

The specific turbulent flame regime

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