Numerical study of The effect of Pilot place on turbulent flame lift off with different levels of inhomogeneity in combustion chamber

Document Type : Original Article

Author

Phd candidate, Mechanical Engineering, Kashan

Abstract

Combustion of a mixture of inhomogeneity reactants is a type of combustion in which the mixing of fuel and air is not complete. This study investigated the numerical effect of the pilot location on the turbulent jet flame lift off height with different levels of inhomogeneity in the combustion chamber. The effect of different equevalence ratios has also been investigated. In this numerical study, the configuration modeling of Navier Stokes equations using Reynolds averaging method, standard k-ε turbulence and reactive flow modeling of Eddy Dissipation Concept (EDC) method have been used. Observations show that the flame lift off height decreases with increasing inhomogeneity length and the flame attach during a certain inhomogeneity length, which depends on the equevalence ratio and pilot location. In all of the cases studied, a range of inhomogeneity lengths was found during which the flame was attached. The results show that the flame lift off height in nonpremixed mode is higher than in the case where the fuel-air mixture ignites almost premixed in the chamber. The higher the equevalence ratio, the lower the flame lift off height. Based on the three locations studied in the side wall for the pilot location and the results obtained, the pilot in the middle area of the side wall had a lower flame lift off height and a higher attached flame range. Also, the flame area inside the chamber changes as the inhomogeneity changes.

Keywords

Main Subjects

References

[1] Barnes, J.C. and Mellor, A.M. Effects of unmixedness in pilotedlean premixed gas-turbine combustors. Journal of Propulsion and Power, 14:967–973, 1998.
[2] T. W. LEE, M. FENTON and R. SHANKLAND," Effects of Variable Partial Premixing on Turbulent Jet Flame Structure," Department of Mechanical and Aerospace Engineering, Arizona State University,1997, Tempe,Arizona 85187-6106.
[3]M. Mansour, "A Concentric Flow Conical Nozzle Burner for Highly Stabilized Partially Premixed Flames", Combustion Science and Technology,152:1, 115-145.
[4] B. RENOU, E. SAMSON, AND A. BOUKHALFA," an experimental study of freely propagating turbulent propane/air flames in stratified inhomogeneous mixtures," Combustion Science and Technology, 2004,176: pp 1867-1890.
[5] A.X. Sengissen, A.V. Giauque, G.S. Staffelbach, M. Porta, W. Krebs, P. Kaufmann, T.J. Poinsot, "Large eddy simulation of piloting effects on turbulent swirling flames," Proceedings of the Combustion Institute 31, 2007, pp 1729-1736.
[6] S. Meares, V.N. Prasad, G. Magnotti, R.S. Barlow, A.R. Masri, "Stabilization of piloted turbulent flames with inhomogeneous inlets," Proceedings of the Combustion Institute 35, 2015, pp 1477–1484.
[7] F. Xiao, Y. Fujiang, G. Zhihui, "Combustion instability of pilot flame in a pilot bluff body stabilized combustor," Chinese Journal of Aeronautics, 2015, 28(6), pp 1606–1615.
[8] K. Kleinheinz, T. Kubis, P. Trisjono, M. Bode, H. Pitsch, "Computational study of flame characteristics of a turbulent piloted jet burner with inhomogeneous inlets," Proceedings of the Combustion Institute 000, 2016, pp 1–11.
[9] B. A. Perry, M. E. Mueller, A. R. Masri, "A two mixture fraction flamelet model for large eddy simulation of turbulent flames with inhomogeneous inlets," Proceedings of the Combustion Institute 36, 2017, pp 1767–1775.
[10] T.F. Guiberti, M. Juddoo, D.A. Lacoste, M.J. Dunn, W.L. Roberts, A.R. Masri, " Fuel effects on the stability of turbulent flames with compositionally inhomogeneous inlets," Proceedings of the Combustion Institute 36, 2017, pp 1777–1784.
[11] S. Galindo, F. Salehi, M.J. Cleary, A.R. Masri, "MMC-LES simulations of turbulent piloted flames with varying levels of inlet inhomogeneity," Proceedings of the Combustion Institute 0, 2016, pp 1–8.
[12] M. S. Mansour, H. Pitsch, S. Kruse, M. F. Zayed, M. S. Senosy, M. Juddoo, J. Beeckmann, A. R. Masri, "A concentric flow slot burner for stabilizing turbulent partially premixed inhomogeneous flames of gaseous fuels," Experimental Thermal and Fluid Science 91, 2018, pp 214–229.
[13] H.C. Cutcher, R.S. Barlow, G. Magnotti, A.R. Masri, "Turbulent flames with compositionally inhomogeneous inlets: Resolved measurements of scalar dissipation rates," Proceedings of the Combustion Institute 000, 2016, pp 1–9.
[14] M. S. Mansour, H. Pitsch, S. Kruse, M. F. Zayed, M. S. Senosy, M. Juddoo, J. Beeckmann, A. R. Masri, "A concentric flow slot burner for stabilizing turbulent partially premixed inhomogeneous flames of gaseous fuels," Experimental Thermal and Fluid Science 91, 2018, pp 214–229.
[15] N. Kim, Y. Kim, "Multi-environment probability density function approach for turbulent partially-premixed methane/air flame with inhomogeneous inlets," Combustion and Flame 182, 2017, pp 190–205.
[16] W. Jin, S. A. Steinmetz, M. Juddoo, M. J. Dunn, Z. Huang, A. R. Masri, "Effects of shear inhomogeneities on the structure of turbulent premixed flames," Combustion and Flame 208, 2019, pp 63–78.
[17] B. E. Van doormaal, G. D. Raithby, 1984. “Enhancements of the SIMPLE method for predicting incompressible fluid flows”, Numerical Heat Transfer, 7, p. 147.
[18]K.Cheong, P. Li, F. Wang, J. Mi, “Emissions of NO and CO from counterflow combustion of CH4 under MILD and oxyfuel conditions”, Energy 124, 652-664.
[19]R. S. BARLOW, A. N. KARPETIS, J. H. FRANK, “Scalar Profiles and NO Formation in Laminar Opposed Flow Partially Premixed Methane/Air Flames”, Combustion Research Facility, Sandia National Laboratories, Livermore, CA 94551, USA.
[20] http://combustion.berkeley.edu/Combustion_ Laboratory/grimech,”Gri2.11 Chemistry and thermodynamic files”.
[21] D. Garréton, O. Simonin, 1994. “Aerodynamics of steady state combustion chambers and furnaces”, ASCF Ercoftac CFD Workshop, EDF Org, Chatou, France.
[22] C. V. Silva , F. H. R. França & H. A. Vielmo (2007) "Analysis of the turbulent, non-premixed combustion of natural gas in a cylindrical chamber with and without thermal radiation", Combustion Science and Technology, 179:8, 1605-1630
[23] A. Jalalian, K. Mazaheri, Comparison of some global chemical kinetics effects on methane lifted flame 3D simulation, Modares Mechanical Engineering, Vol. 17, No. 8, pp. 207-216, 2017 (in Persian)
[24] C. V. da Silva, H. A. Vielmo, F. H. R. Franca, 2005. “Numerical Simulation of the Combustion of Methane and Air in a Cylindrical Chamber”, 18th International Congress of Mechanical Engineering, Ouro Preto.
[25] X. Qin, I. K. Puri and S. K. Aggarwal. " Characteristics of lifted triple flames stabilized in the near field of a partially premixed axisymmetric jet ", Proceedings of the Combustion Institute, Volume 29, 2002/pp. 1565–1572.

Files

History

  • Receive Date: 09 June 2020
  • Revise Date: 29 August 2020
  • Accept Date: 19 September 2020

Share

How to cite

Statistics