Study of the instability of the annular liquid sheet exiting from the effervescent atomizer at high aeration ratios

Document Type : Original Article

Authors

1 Design expert- The combustion department of Turbotec company

2 Energy Conversion Group, Faculty of Mechanical Engineering

3 Director of Test and Performance Department, Combustion Chamber Group, Middle East Single Turbocharger Company

Abstract

In many atomizers, the breakup of the annular liquid sheet exiting from the atomizer is responsible for the formation of the spray and the determination of the spray characteristics. This paper studies the instability of the annular liquid sheet exiting from the effervescent atomizer at high gas to liquid mass flow ratios, in order to better understand the primary breakup process in this type of atomizer. Therefore, the dispersion equation obtained from the 3D linear stability analysis has been solved for the flow conditions of the annular liquid sheet exiting from the effervescent atomizer at 0.38 L/min liquid flow rate and high aeration ratios of 1.24% and 1.84%. The results showed that in the aerated ratios studied, the axisymmetric para-sinusoidal perturbation modes are the predominant in the breakup of the annular liquid sheet. In addition, it was observed that with increasing aeration ratio, the liquid sheet will breakup at shorter wave lengths. Also, the results of the study of the effect of viscosity on the instability of the annular liquid sheet showed that the viscosity of the liquid has some stabilizing effects and non-viscose assumption of the liquid at high aeration ratios can cause errors in calculations of the stability of the annular sheet breakup and the breakup length.

Keywords

References

  1. B. Bai, Y.M. Xing, Z. Wang., “Experiment Study and Simulation Research for the Atomization Characteristics of the Internal-Mixing Twin-Fluid Atomizer,” in Advanced Materials Research, 1049, 2014, pp. 1075-1082.
  2. D. Sovani, P. E. Sojka, A. H. Lefebvre, “Effervescent Atomization,” Progress in Energy and Combustion Science, Vol. 27 (4), 2001, pp. 483-521.
  3. Lefebvre and R. Ballal, GAS Turbine Combustion: Alternative Fuels and Emissions, Third Edition, CRC press, 2010.
  4. Sarkar and K. Ramamurthi, “Flow visualization of sprays formed by bubbly, slug, and annular flows in an effervescent atomizer,” Journal of Flow Visualization & Image Processing, Vol. 14 (4), 2007, pp. 397-408.
  5. LÓ§rcher, F. Schmidt, D. Mewes, “Effervescent atomization of liquids,” Atomization and Sprays, Vol. 15 (2), 2005, pp. 145-168.
  6. Y. Kim, S. Y. Lee, “Dependence of spraying performance on the internal flow pattern in effervescent atomizers,” Atomization and Sprays, Vol. 11 (6), 2001, pp. 735-756.
  7. Jedelsky, M. Jicha, “Unsteadiness in effervescent sprays: a new evolution method and influence of operational conditions,” Atomization and Sprays, Vol. 18 (1), 2008, pp. 49-83.
  8. J. Qian, J. Z. Lin, H. B. Xiong, “A Fitting formula for predicting droplet mean diameter for various liquid in effervescent atomization spray,” Journal of Thermal Spray Technology, Vol. 19 (3), 2010, pp. 586-601.
  9. Du, X. Li, “Effect of gas stream swirls on the instability of viscous annular liquid jets,” Acta Mechanica, Vol. 176 (1-2), 2005, pp. 61-81.
  10. P. Herrero, E. M. Del Valle, M. A. Galan, “Instability study of a swirling annular liquid sheet of polymer produced by air-blast atomization,” Chemical Engineering Journal, Vol. 133 (1-3), 2007, pp. 69-77.
  11. H. Moosavi, F. Ommi, “Determining the characteristics of the primary breakup of the liquid plate exiting from airblast atomizer by nonlinear investigation of instability in the liquid plate,” Fluid Mechanics and Aerodynamics, 2015, Vol. 3(2), pp. 11.  
  12. Shen, X. Li, “Instability of an annular viscosity liquid jet,” Acta Mechanica, Vol. 114 (12), 1996, pp. 167-183.
  13. Yan, Z. Ning, M. Lü, C. Sun, J. Fu, Y. Li, “Spatial instability in annular swirling viscous liquid sheet,” Physics of Fluid, Vol. 27 (2), 2015, 024101.
  14. Alizadeh Kaklar, M. R. Ansari, J. Alizadeh Kaklar, “Study of the instability of the perturbation modes of the annular liquid sheet exiting from the effervescent atomizer,” 28th Annual International Conference of Iranian Society of Mechanical Engineering, 2020.(In Persian)
  15. Alizadeh Kaklar, M. R. Ansari, J. Alizadeh Kaklar, “Investigation of the effect of viscosity on the instability of the annular liquid sheet exiting from the effervescent atomizer,” 29th Annual International Conference of the Iranian Association of Mechanical Engineers and the 8th Conference on Thermal Power Plants, 2021.(In Persian)
  16. Alizadeh Kaklar, M. R. Ansari, “Numerical study of the 3D internal flow field of effervescent atomizer at different aeration levels,” Fuel and combustion, Vol. 13 (4), 2020, pp. 25-42.(In Persian)
  17. Alizadeh Kaklar, M. R. Ansari, “Simulates the internal flow field of an injector and the linear instability studying of the exiting annular liquid  sheet,” PhD Thesis, Department of Mechanical Engineering, Tarbiat Modares University, Tehran, 2018. (In Persian) 
  18. Shen, “Formation and characteristics of sprays from annular viscous liquid jet breakup,”  Doctoral dissertation, Department of Mechanical Engineering, University of Victoria, Canada, 1997.
  19. Liao, S. Jeng, M. A. Jog, M. A. Benjamin, “Instability of an annular liquid sheet surrounded by swirling airstreams,” AIAA Journal, Vol. 38 (12), 2000, pp. 453-460.

 

 

 

Files

History

  • Receive Date: 05 March 2022
  • Revise Date: 07 May 2022
  • Accept Date: 13 June 2022

Share

How to cite

Statistics