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Primary Atomization in an Airblast Gas Turbine Atomizer

  • L. Opfer
  • I. V. Roisman
  • C. Tropea
Chapter
Part of the Fluid Mechanics and Its Applications book series (FMIA, volume 1581)

Abstract

This study focuses on the spray atomization, transport and impact on a solid substrate under cross-flow conditions, as used in airblast atomizers with prefilmers for aero engines and gas turbines. The phenomena are observed using a high-speed video system and the spray is characterized using the phase Doppler technique. The governing mechanisms of drop formation, wall collision and aerodynamic breakup are identified. It is shown that three different mechanisms are mainly responsible for the formation of single drops from the bulk liquid. These are: primary atomization, breakup of the liquid wall film and further aerodynamic breakup of droplets. Finally, an atomization model is developed, which accounts for primary atomization, wall film formation and aerodynamic breakup. The model predicts the distribution of the drop diameters and velocities in the generated spray. The agreement between the model predictions and the experimental data is very good.

Keywords

Atomization Airblast atomizer Spray impact Aerodynamic breakup 

Notes

Acknowledgements

The authors acknowledge the financial support from the German Research Council (DFG) through the SFB568.

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Copyright information

© Springer Science+Business Media Dordrecht 2013

Authors and Affiliations

  1. 1.Institute of Fluid Mechanics and Aerodynamics, Mechanical EngineeringTechnische Universität DarmstadtDarmstadtGermany
  2. 2.Center of Smart Interfaces, Mechanical EngineeringTechnische Universität DarmstadtDarmstadtGermany

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