Experiments in Fluids

, 59:151 | Cite as

Characterization of wall filming and atomization inside a gas-turbine swirl injector

  • K. P. Shanmugadas
  • S. R. Chakravarthy
  • R. Narasimha Chiranthan
  • Jayanth Sekar
  • Sundar Krishnaswami
Research Article


The internal atomization characteristics of a practical gas turbine fuel injector are investigated comprehensively using various laser flow diagnostic techniques. The injector consists of a pilot spray surrounded by a primary swirl air, with the spray impinging on a venturi prefilmer to form a liquid film that accumulates into a rim at the venturi tip, which in turn is sheared by a counter-rotating secondary swirl air. The atomizer geometry is modularized into different configurations to access the internal flow field. The quantitative measurements made are with a phase Doppler interferometer at different stages of the injector and time-resolved volume or planar laser induced fluorescence (TR-V/PLIF) imaging. The different internal atomization characteristics such as the liquid film thickness variation, size distribution of craters formed by primary spray droplets impinging on the liquid film, rim thickness at the venturi tip, and droplet size and velocity distribution at different stages are measured. It is found that the film dynamics is influenced by the droplet splashing and the shearing action of the primary air. The liquid rim at the venturi tip is the major source of droplets at the injector exit rather than the liquid film. The unsteady evolution of the multiphase flow inside the injector is dictated by the precessing vortex core of the primary swirl. However, the atomization process is mainly influenced by the central toroidal recirculation zone of the primary swirl flow and the counter-rotating shear layer acting on the accumulated liquid rim at the venturi tip.

Graphical abstract



We acknowledge GE India Industrial PVT. LTD., Bengaluru for the financial support and for providing the nozzle hardware. The National Centre for Combustion R&D is supported by the Science and Engineering Research Board, India.


  1. Aigner M, Wittig S (1988) Swirl and counterswirl effects in prefilming airblast atomizers. J Eng Gas Turb Power 110(1):105–110CrossRefGoogle Scholar
  2. Bachalo WD, Houser MJ (1984) Phase/doppler spray analyzer for simultaneous measurements of drop size and velocity distributions. Opt Eng 23(5):235583CrossRefGoogle Scholar
  3. Barun S, Weith L, Koch R, Bauer H-J (2015) Influence of trailing edge height on primary atomization: numerical studies applying the smoothed particle hydrodynamics (SPH) method. In: 13th Triennial international conference on liquid atomization and spray systems, TaiwanGoogle Scholar
  4. Batarseh FZ (2008) Spray generated by an airblast atomizer: atomization, propagation and aerodynamic instability. PhD Thesis, TU DarmstadtGoogle Scholar
  5. Batarseh FZ, GnirB M, Roisman IV, Tropea C (2009) Fluctuations of a spray generated by an airblast atomizer. Exp Fluids 46:1081–1091CrossRefGoogle Scholar
  6. Bhayaraju U, Hassa C (2009) Planar liquid sheet breakup of prefilming and non-prefilming atomizers at elevated pressures. Atomization Sprays 19:1147–1169CrossRefGoogle Scholar
  7. Brundish KD, Miller MN, Morgan LC, Wheatley AJ (2003) Variable fuel placement injector development. In: ASME Turbo Expo 2003, Atlanta, Georgia, USA, GT2003-38717Google Scholar
  8. Cai J, Fu Y, Elkady A, Jeng S, Mongia HC (2003) Swirl cup modelling part 4: effect of confinement on flow characteristics. In: 41st AIAA aerospace sciences meeting and exhibit, Reno, Nevada, AIAA Paper 2003-486Google Scholar
  9. Elshanawany MS, Lefebvre AH (1980) Airblast atomization—effect of linear scale on mean drop size. J Energy (4):184–189Google Scholar
  10. Foust M, Thomsen D, Stickles R, Cooper C, Dodds W (2012) Development of the GE Aviation low emissions TAPS combustor for next-generation aircraft Engines. In: 50th AIAA aerospace sciences meeting, Nashville, Tennessee, USA, AIAA paper 2012-936Google Scholar
  11. Gepperth S, Guildenbecher D, Koch R, Bauer H-J (2010) Prefilming primary atomization: experiments and modelling. In: 23rd Annual conference on liquid atomization and spray systems, ILASS Europe, Brno, Chech RepublicGoogle Scholar
  12. Gepperth S, Muller A, Koch R, Bauer H-J (2012) Ligament and droplet characteristics in prefilming airblast atomization. In: 12th Triennial international conference on liquid atomization and spray systems, ICLASS 2012, Heidelberg, GermanyGoogle Scholar
  13. Gepperth S, Koch R, Bauer H-J (2013) Analysis and comparison of primary droplet characteristics in the near field of a prefilming airblast atomizer. In: ASME. Turbo Expo: Power for Land, Sea, and Air, Volume 1A: Combustion, Fuels and Emissions, pp V01AT04A002Google Scholar
  14. Gupta AK (1997) Gas turbine combustion: prospects and challenges. Energy Convers Manag 38:1311–1318CrossRefGoogle Scholar
  15. Gupta AK, Lilley DG, Syred N (1984) Swirl flows. Abacus Press, Tunbridge WellsGoogle Scholar
  16. Gurubaran K, Chakravarthy SR, Sujith RI (2008) Characterization of a prefilming airblast atomizer in a strong swirl flow field. J Propul Power 24:1124–1132CrossRefGoogle Scholar
  17. Hsiang L-P, Faeth GM (1992) Near-limit drop deformation and secondary breakup. Int J Multiph Flow 18(5):635–652CrossRefGoogle Scholar
  18. Hsiao G, Mongia HC (2003) Swirl cup modelling part III: Grid independent solution with different Turbulence Models. In: 41st AIAA aerospace sciences meeting and exhibit, Reno, Nevada, AIAA Paper 2003-1349Google Scholar
  19. Huang Y, Yang V (2009) Dynamics and stability of lean-premixed swirl-stabilized combustion. Prog Energy Combust Sci 35:293–364CrossRefGoogle Scholar
  20. Inamura T, Shirota M, Tsushima M, Kato M, Hamajima S, Sato A (2012) Spray characteristics of prefilming type of airblast atomizer. In: 12th Triennial international conference on liquid atomization and spray systems, ICLASS 2012, Heidelberg, GermanyGoogle Scholar
  21. Jasuja AK (2006) Behaviour of aero-engine airblast sprays in practical environments. In:10th Triennial international conference on liquid atomization and spray systems, ICLASS 2006, Kyoto, JapanGoogle Scholar
  22. Jeng S-M, Flohre N, Mongia HC (2004) Swirl Cup Modeling-part IX: liquid atomization modelling. In: 42nd AIAA aerospace sciences meeting and exhibit, Reno, Nevada, USA, AIAA Paper 2004-137Google Scholar
  23. Lefebvre AH (1975) Pollution control in continuous combustion engines. 15th Symp (Int) Combust 15(1):1169–1180MathSciNetCrossRefGoogle Scholar
  24. Lefebvre AH (1980) Airblast atomization. Prog Energy Combust Sci 6:233–261CrossRefGoogle Scholar
  25. Lefebvre AH (1992) Twin-fluid atomization: Factors influencing mean drop size. Atomization Sprays 2:101–119CrossRefGoogle Scholar
  26. Lin Y, Lin Yu, Liu G (2009) Unsteady flow structures of a counter-rotating swirl cup. In: 45th AIAA/ASME/SAE/ASEE joint propulsion conference and exhibit, Denver, Colorado, USA, AIAA paper 2009-2016Google Scholar
  27. McDonell VG, Seay JE, Samuelsen S (1994) Characterization of the non-reacting two-phase flow downstream of an aero-engine combustor dome operating at realistic conditions In: ASME International gas turbine and aero-engine congress and exposition, Hague, Netherlands, ASME Paper 1994- GT-263Google Scholar
  28. Mongia HC, Al-Roub M, Danis A, Elliott-Lewis D, Jeng S, Johnson A, McDonell V, Samuelsen G, Vise S (2001) Swirl cup modelling part 1. In: 37th joint propulsion conference and exhibit, Salt Lake City, UT, USA, AIAA Paper 2001-3576Google Scholar
  29. Rajamanickam K, Basu S (2017a) On the dynamics of vortex—droplet interactions, dispersion and breakup in a coaxial swirling flow. J Fluid Mech 827:572–613MathSciNetCrossRefGoogle Scholar
  30. Rajamanickam K, Basu S (2017b) Insights into the dynamics of spray—swirl interactions. J Fluid Mech 810:82–126MathSciNetCrossRefGoogle Scholar
  31. Rizk NK, Lefebvre AH (1980) The Influence of liquid-film thickness on airblast atomization. J Eng Power 102(3):706–710CrossRefGoogle Scholar
  32. Rizk NK, Lefebvre AH (1983) Spray characteristics of plain-jet airblast atomizers. J Eng Gas Turbines Power 106(3):634–638CrossRefGoogle Scholar
  33. Rizkalla AA, Lefebvre AH (1975) The Influence of air and liquid properties on airblast atomization. J Fluids Eng 97(3):316–320CrossRefGoogle Scholar
  34. Rodríguez DJ, Shedd TA (2004) Entrainment of gas in the liquid film of horizontal annular two-phase flow. Int J Multiph Flow 30(6):565–583CrossRefGoogle Scholar
  35. Roisman IV, Tropea C (2002) Impact of a drop onto a wetted wall: description of crown formation and propagation. J Fluid Mech 472:373–397MathSciNetCrossRefGoogle Scholar
  36. Roisman IV, Tropea C (2005) Fluctuating flow in a liquid layer and secondary spray created by an impacting spray. Int J Multiph Flow 31(2):179–200CrossRefGoogle Scholar
  37. Roisman IV, Hinsberg NP, Tropea C (2008) Propagation of a kinematic instability in a liquid layer: capillary and gravity effects. Phys Rev E 77:046305CrossRefGoogle Scholar
  38. Sattelmayer T, Wittig S (1986) Internal flow effects in prefilming airblast atomizers—mechanisms of atomization and droplet spectra. J Eng Gas Turb Power 108:465–472CrossRefGoogle Scholar
  39. Schildmacher KU, Koch R, Wittig S, Krebs W, Hoffmann S (2000) Experimental investigations of the temporal air-fuel mixing fluctuations and cold flow instabilities of a premixing gas turbine burner. In: ASME Turbo Expo 2000: power for land, sea, and air. Munich, Germany, ASME Paper 2000-GT-0084Google Scholar
  40. Schubring D, Ashwood AC, Shedd TA, Hurlburt ET (2010) Planar laser-induced fluorescence (PLIF) measurements of liquid film thickness in annular flow Part I: methods and data. Int J Multiph Flow 36(10):815–824CrossRefGoogle Scholar
  41. Shanmugadas KP, Chakravarthy SR (2017) A canonical geometry to study wall filming and atomization in prefilming coaxial swirl injectors. Proc Combust Inst 36(2):2467–2474CrossRefGoogle Scholar
  42. Sivakumar D, Tropea C (2002) Splashing impact of a spray onto a liquid film. Phys Fluids 14:L85CrossRefGoogle Scholar
  43. Syred N (2006) A review of oscillation mechanisms and the role of the precessing vortex core (PVC) in swirl combustion systems. Prog Energy Combust Sci 32:93–161CrossRefGoogle Scholar
  44. Syred N, Beer JM (1974) Combustion in swirling flows: a review. Combust Flame 23(2):143–201CrossRefGoogle Scholar
  45. Wang HY, McDonnel VG, Samuelsen GS (1992) The two-phase flow downstream of a production engine combustor swirl cup. Symp (Int) Combust 24(1):1457–1463CrossRefGoogle Scholar
  46. Wang H, McDonell VG, Sows WA, Samuelsen S (1994) Experimental study of a model gas turbine combustor swirl cup, Part 11: droplet dynamics. J Propul Power 10:446–452CrossRefGoogle Scholar
  47. Wang HY, McDonnel VG, Samuelsen GS (1995) Influence of hardware design on the flow field structures and the patterns of droplet dispersion: Part I—mean quantities. J Eng Gas Turbine Power 117:282–289CrossRefGoogle Scholar
  48. Wang SW, Yang V, Hsia G, Hsieh SY, Mongia HC (2007) Large-eddy simulations of gas-turbine swirl injector flow dynamics. J Fluid Mech 583:99–122CrossRefGoogle Scholar

Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of Aerospace Engineering, and National Centre for Combustion Research and DevelopmentIndian Institute of Technology MadrasChennaiIndia
  2. 2.GE India Industrial Pvt. Ltd.BengaluruIndia

Personalised recommendations