An Analysis of Turbulent Mixing Effects on the Soot Formation in High Pressure n-dodecane Sprays

  • Muhammad F. A. Razak
  • Fatemeh SalehiEmail author
  • Muhammad A. Chishty


An n-dodecane spray flame, known as Spray A, is simulated under the diesel engine conditions. The simulations are based on the well-mixed assumption where the turbulence-chemistry interactions are ignored, and employ the semi-empirical multi-step Moss-Brookes soot model coupled with the Reynolds-averaged turbulence model and a Lagrangian discrete phase spray model. A 54-species reduced n-dodecane chemical mechanism is employed in all simulations to evaluate the reaction rates. The importance of the turbulent mixing on the soot formation is analysed using three different turbulent Schmidt numbers; Sct = 0.7, 1.1 and 1.4. The non-reacting case is first validated using the mixture fraction and the velocity fields. It is found that the jet velocity and penetration length are unaffected by Sct for the inert case, however, the mixture fraction is sensitive to Sct where Sct = 1.1 leads to an excellent agreement with the measurements. Reacting simulations are compared with experimental data in terms of the ignition delay and the flame lift-off length. The results confirm the ignition delay time is marginally affected by changes in Sct. At the baseline condition, Sct = 0.7 and 1.1 result in a very similar value for the lift-off length which is in good agreement with the experiment although at higher ambient temperatures, only Sct = 0.7 agrees well with the measurements. It is found that the formation of formaldehyde and acetylene increases as the level of mixing decreases while the trend is opposite for the OH mass fraction. Consequently, with increasing Sct the soot volume fraction increases and the soot-containing region is extended. The results show that the development of the soot mass is not well captured, regardless of the value of the turbulent Schmidt number.


Soot formation Spray A Engine combustion network (ECN) Turbulent Schmidt number 



This work is funded by the Malaysian People’s Trust Council (Majlis Amanah Rakyat). The authors acknowledge the computational resources and the software licence provided by the University of Sydney and Macquarie University.

Compliance with Ethical Standards

Conflict of Interest

The authors declare that they have no conflict of interest.


  1. 1.
    Lawler, B., Splitter, D., Szybist, J., Kaul, B.: Thermally stratified compression ignition: a new advanced low temperature combustion mode with load flexibility. Appl. Energ. 189, 122–132 (2017)Google Scholar
  2. 2.
    Reitz, R.D., Duraisamy, G.: Review of high efficiency and clean reactivity controlled compression ignition (RCCI) combustion in internal combustion engines. Prog. Energy Combust. Sci. 46, 12–71 (2015)Google Scholar
  3. 3.
    Salehi, F., Talei, M., Hawkes, E.R., Bhagatwala, A., Chen, J.H., Yoo, C.S., Kook, S.: Doubly conditional moment closure modelling for HCCI with temperature inhomogeneities. Proc. Combust. Inst. 36(3), 3677–3685 (2017)Google Scholar
  4. 4.
    Salehi, F., Talei, M., Hawkes, E.R., Yoo, C.S., Lucchini, T., D’Errico, G., Kook, S.: Conditional moment closure modelling for HCCI with temperature inhomogeneities. Proc. Combust. Inst. 35(3), 3087–3095 (2015)Google Scholar
  5. 5.
    Dellinger, B., A. D'Alessio, A. D’Anna, A. Ciajolo, B. Gullett, H. Henry, M. Keener, J. Lighty, S. Lomnicki, D. Lucas, G. Oberdörster, P. Demetrio, W. Suk, A. Sarofim, K. R Smith, T. Stoeger, P. Tolbert, R. Wyzga and R. Zimmermann, Report: Combustion Byproducts and Their Health Effects: Summary of the 10th International Congress. Vol. 25. 2008. 1107–1114Google Scholar
  6. 6.
    Johnson, T.V.: Diesel Emission Control: 2001 in Review. SAE International (2002)Google Scholar
  7. 7.
    Lloyd, A.C., Cackette, T.A.: Diesel engines: environmental impact and control. J. Air Waste Manag. Assoc. 51(6), 809–847 (2001)Google Scholar
  8. 8.
    Prasad, R., Bella, V.R.: A review on diesel soot emission, its effect and control. Bulletin of Chemical Reaction Engineering & Catalysis. 5(2), 69–86 (2011)Google Scholar
  9. 9.
    Zhao, F., Asmus, T.W., Assanis, D.N., Dec, J.E., Eng, J.A., Najt, P.M.: Homogeneous charge compression ignition (HCCI) engines: key research and development issues PT-94. Prog. Technol. 94 (2003)Google Scholar
  10. 10.
    Engine combustion network. Available from: Accessed 11 August 2017
  11. 11.
    Bhattacharjee, S., Haworth, D.C.: Simulations of transient n-heptane and n-dodecane spray flames under engine-relevant conditions using a transported PDF method. Combust. Flame. 160(10), 2083–2102 (2013)Google Scholar
  12. 12.
    Chishty, M.A., Bolla, M., Hawkes, E., Pei, Y., Kook, S.: Assessing the importance of radiative heat transfer for ECN spray a using the transported PDF method. SAE Int. J. Fuels Lubr. 9(1), 100–107 (2016)Google Scholar
  13. 13.
    Chishty, M.A., Bolla, M., Hawkes, E.R., Pei, Y., Kook, S.: Soot formation modelling for n-dodecane sprays using the transported PDF model. Combust. Flame. 192, 101–119 (2018)Google Scholar
  14. 14.
    D’Errico, G., Lucchini, T., Contino, F., Jangi, M., Bai, X.-S.: Comparison of well-mixed and multiple representative interactive flamelet approaches for diesel spray combustion modelling. Combust. Theor. Model. 18(1), 65–88 (2014)MathSciNetGoogle Scholar
  15. 15.
    Pei, Y., Hawkes, E.R., Kook, S., Goldin, G.M., Lu, T.: Modelling n-dodecane spray and combustion with the transported probability density function method. Combust. Flame. 162(5), 2006–2019 (2015)Google Scholar
  16. 16.
    Bekdemir, C., Somers, L., De Goey, L.: Modeling diesel engine combustion using pressure dependent flamelet generated manifolds. Proc. Combust. Inst. 33(2), 2887–2894 (2011)Google Scholar
  17. 17.
    Pei, Y., Som, S., Pomraning, E., Senecal, P.K., Skeen, S.A., Manin, J., Pickett, L.M.: Large eddy simulation of a reacting spray flame with multiple realizations under compression ignition engine conditions. Combustion and Flame. 162(12), 4442–4455 (2015)Google Scholar
  18. 18.
    Salehi, F., Cleary, M., Masri, A., Ge, Y., Klimenko, A.: Sparse-Lagrangian MMC simulations of an n-dodecane jet at engine-relevant conditions. Proc. Combust. Inst. 36(3), 3577–3585 (2017)Google Scholar
  19. 19.
    Salehi, F., M.J. Cleary and A.R. Masri, A sensitivity analysis for sparse-Lagrangian MMC in simulations of a n-dodecane reacting jet, SAE technical paper, 2016-01-0859, 2016 Google Scholar
  20. 20.
    Wehrfritz, A., Kaario, O., Vuorinen, V., Somers, B.: Large eddy simulation of n-dodecane spray flames using flamelet generated manifolds. Combust. Flame. 167, 113–131 (2016)Google Scholar
  21. 21.
    Bolla, M., Farrace, D., Wright, Y.M., Boulouchos, K., Mastorakos, E.: Influence of turbulence–chemistry interaction for n-heptane spray combustion under diesel engine conditions with emphasis on soot formation and oxidation. Combust. Theor. Model. 18(2), 330–360 (2014)Google Scholar
  22. 22.
    Reitz, R.D.: Directions in internal combustion engine research. Combust. Flame. 160(1), 1–8 (2013)MathSciNetGoogle Scholar
  23. 23.
    Wang, H., Ra, Y., Jia, M., Reitz, R.D.: Development of a reduced n-dodecane-PAH mechanism and its application for n-dodecane soot predictions. Fuel. 136, 25–36 (2014)Google Scholar
  24. 24.
    Vishwanathan, G., Reitz, R.D.: Development of a practical soot modeling approach and its application to low-temperature diesel combustion. Combust. Sci. Technol. 182(8), 1050–1082 (2010)Google Scholar
  25. 25.
    Pang, K.M., H.M. Poon, H.K. Ng, S. Gan and J. Schramm, Soot formation modeling of n-dodecane and diesel sprays under engine-like conditions SAE Technical Paper 2015-24-2468, 2015Google Scholar
  26. 26.
    Leung, K.M., Lindstedt, R.P., Jones, W.: A simplified reaction mechanism for soot formation in nonpremixed flames. Combust. Flame. 87(3–4), 289–305 (1991)Google Scholar
  27. 27.
    Hiroyasu, H. and T. Kadota, Models for combustion and formation of nitric oxide and soot in DI diesel engines, SAE Technical Paper 760129, 1976Google Scholar
  28. 28.
    Tominaga, Y., Stathopoulos, T.: Turbulent Schmidt numbers for CFD analysis with various types of flowfield. Atmos. Environ. 41(37), 8091–8099 (2007)Google Scholar
  29. 29.
    Yao, T., Pei, Y., Zhong, B.-J., Som, S., Lu, T., Luo, K.H.: A compact skeletal mechanism for n-dodecane with optimized semi-global low-temperature chemistry for diesel engine simulations. Fuel. 191, 339–349 (2017)Google Scholar
  30. 30.
    Wang, H., X. You, A.V. Joshi, S.G. Davis, A. Laskin, F. Egolfopoulos and C. Law, USC Mech Version II. High-temperature combustion reaction model of H2/CO/C1-C4 compounds. 2007Google Scholar
  31. 31.
    Vié, A., Franzelli, B., Gao, Y., Lu, T., Wang, H., Ihme, M.: Analysis of segregation and bifurcation in turbulent spray flames: a 3D counterflow configuration. Proc. Combust. Inst. 35(2), 1675–1683 (2015)Google Scholar
  32. 32.
    You, X., Egolfopoulos, F.N., Wang, H.: Detailed and simplified kinetic models of n-dodecane oxidation: the role of fuel cracking in aliphatic hydrocarbon combustion. Proc. Combust. Inst. 32(1), 403–410 (2009)Google Scholar
  33. 33.
    Moiz, A.A., Ameen, M.M., Lee, S.-Y., Som, S.: Study of soot production for double injections of n-dodecane in CI engine-like conditions. Combustion and Flame. 173, 123–131 (2016)Google Scholar
  34. 34.
    Davidovic, M., T. Falkenstein, M. Bode, L. Cai, S. Kang, J. Hinrichs, H.J.O. Pitsch, G. Science and T.R.d.I.E. nouvelles, LES of n-dodecane spray combustion using a multiple representative interactive Flamelets model. Oil Gas Sci. Technol. , 2017. 72(5): p. 29Google Scholar
  35. 35.
    Frassoldati, A., D'Errico, G., Lucchini, T., Stagni, A., Cuoci, A., Faravelli, T., Onorati, A., Ranzi, E.: Reduced kinetic mechanisms of diesel fuel surrogate for engine CFD simulations. Combust. Flame. 162(10), 3991–4007 (2015)Google Scholar
  36. 36.
    Chishty, M., M. Bolla, Y. Pei, E. Hawkes and S. Kook. A Numerical Study of ‘Spray A’with Multiple-Injections Using the Transported PDF Method. in 10th ASPACC Conference. 2015Google Scholar
  37. 37.
    Pei, Y., Davis, M.J., Pickett, L.M., Som, S.: Engine combustion network (ECN): global sensitivity analysis of spray a for different combustion vessels. Combust. Flame. 162(6), 2337–2347 (2015)Google Scholar
  38. 38.
    Frossling, N., Evaporation, heat transfer, and velocity distribution in two-dimensional and rotationally symmetrical laminar boundary-layer flow. 1956, National Aeronautics and Space Admin Langley Research CentersGoogle Scholar
  39. 39.
    Ranz, W., Marshall, W.R.: Evaporation from drops. Chem. Eng. Prog. 48(3), 141–146 (1952)Google Scholar
  40. 40.
    Morsi, S., Alexander, A.: An investigation of particle trajectories in two-phase flow systems. J. Fluid Mech. 55(2), 193–208 (1972)zbMATHGoogle Scholar
  41. 41.
    Clift, R., Grace, J.R., Weber, M.E.: Bubbles, drops, and particles. Courier Corporation (2005)Google Scholar
  42. 42.
    Brookes, S., Moss, J.B.: Predictions of soot and thermal radiation properties in confined turbulent jet diffusion flames. Combust. Flame. 116(4), 486–503 (1999)Google Scholar
  43. 43.
    Bolla, M., Chishty, M.A., Hawkes, E.R., Chan, Q.N., Kook, S.: Influence of turbulent fluctuations on radiation heat transfer, NO and soot formation under ECN spray a conditions. Proc. Combust. Inst. 36(3), 3551–3558 (2017)Google Scholar
  44. 44.
    Lindstedt, P.R., Simplified soot nucleation and surface growth steps for non-premixed flames, in Soot Formation in Combustion. 1994, Springer. p. 417–441Google Scholar
  45. 45.
    Hall, R., M. Smooke and M. Colket, Predictions of soot dynamics in opposed jet diffusion flames. Physical Chemical Aspects of Combustion: a Tribute to Irvin Glassman, 1997. 4: p. 189–229Google Scholar
  46. 46.
    Ong, J.C., Pang, K.M., Walther, J.H., Ho, J.-H., Ng, H.K.: Evaluation of a Lagrangian soot tracking method for the prediction of primary soot particle size under engine-like conditions. J. Aerosol Sci. 115, 70–95 (2018)Google Scholar
  47. 47.
    Pang, K.M., Jangi, M., Bai, X.-S., Schramm, J.: Evaluation and optimisation of phenomenological multi-step soot model for spray combustion under diesel engine-like operating conditions. Combust. Theor. Model. 19(3), 279–308 (2015)Google Scholar
  48. 48.
    Skeen, S.A., J. Manin, K. Dalen and L.M. Pickett. Extinction-based imaging of soot processes over a range of diesel operating conditions. in 8th US National Combustion Meeting. 2013Google Scholar
  49. 49.
    Skeen, S.A., Manin, J., Pickett, L.M., Cenker, E., Bruneaux, G., Kondo, K., Aizawa, T., Westlye, F., Dalen, K., Ivarsson, A.: A progress review on soot experiments and modeling in the engine combustion network (ECN). SAE Int. J. Engines. 9(2), 883–898 (2016)Google Scholar
  50. 50.
    Pickett, L.M., Genzale, C.L., Bruneaux, G., Malbec, L.-M., Hermant, L., Christiansen, C., Schramm, J.: Comparison of diesel spray combustion in different high-temperature, high-pressure facilities. SAE Int. J. Engines. 3(2), 156–181 (2010)Google Scholar
  51. 51.
    Pei, Y., Hawkes, E.R., Kook, S.: A comprehensive study of effects of mixing and chemical kinetic models on predictions of n-heptane jet ignitions with the PDF method. Flow, Turbul. Combust. 91(2), 249–280 (2013)Google Scholar
  52. 52.
    Pickett, L.M., Manin, J., Payri, R., Bardi, M., Gimeno, J.: Transient rate of injection effects on spray development. SAE Technical Paper 2013-24-0001, 2013Google Scholar
  53. 53.
    Diesel Rate of Injection Available from: Accessed 11 August 2017
  54. 54.
    Payri, R., Salvador, F., Gimeno, J., Bracho, G.: A new methodology for correcting the signal cumulative phenomenon on injection rate measurements. Exp. Tech. 32(1), 46–49 (2008)Google Scholar
  55. 55.
    Pickett, L.M., Manin, J., Genzale, C.L., Siebers, D.L., Musculus, M.P., Idicheria, C.A.: Relationship between diesel fuel spray vapor penetration/dispersion and local fuel mixture fraction. SAE Int. J. Engines. 4(1), 764–799 (2011)Google Scholar
  56. 56.
    Meijer, M. and L. Somers. Engine combustion network: Spray A basic measurements and advanced diagnostics. in Proceedings of the 12th International Conference on Liquid Atomization and Spray Systems, ICLASS 2012, 2-6 September 2012, Heidelberg, Germany. 2012Google Scholar

Copyright information

© Springer Nature B.V. 2019

Authors and Affiliations

  1. 1.School of Aerospace, Mechanical and Mechatronic Engineeringthe University of SydneySydneyAustralia
  2. 2.School of EngineeringMacquarie UniversitySydneyAustralia
  3. 3.School of Civil Engineeringthe University of SydneySydneyAustralia

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