Experiments in Fluids

, Volume 39, Issue 4, pp 651–666 | Cite as

Experimental analysis of liquid–gas interface at low Weber number: interface length and fractal dimension

  • Christophe Dumouchel
  • Jean Cousin
  • Kaëlig Triballier
Research Article

Abstract

The present paper reports an experimental investigation on atomizing liquid flows produced by simplified cavity nozzles. The Weber number being kept low, the sprays produced by these injectors depend on the liquid flow characteristics only, and more precisely, on the non-axial kinetic energy and of the turbulent kinetic energy at the nozzle exit. The investigation reported here concentrates on the characterization of liquid flows during atomization by measuring the spatial variation of the local interface length and of the local interface fractal dimension. Both parameters were found representative of the physics of atomization process: they depend on the characteristics of the flow issuing from the nozzle and they are related to the subsequent drop size distribution. The local interface length is representative of the amount of liquid–gas interface surface area, and is a function of both the non-axial and the turbulent kinetic energies at the nozzle exit. The fractal dimension is representative of the tortuosity of the liquid–gas interface and, as expected, is mainly related to the turbulent kinetic energy at the nozzle exit. As far as the drop size distribution is concerned, it is found that the local interface length at the instant of break-up determines a representative drop diameter of some kind, whereas the fractal dimension at the same instant controls the dispersion of the distribution.

Notes

Acknowledgments

The authors would like to warmly thank Cyril Mauger for his precious help in the present experimental work.

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Copyright information

© Springer-Verlag 2005

Authors and Affiliations

  • Christophe Dumouchel
    • 1
  • Jean Cousin
    • 1
  • Kaëlig Triballier
    • 1
  1. 1.UMR 6614—CORIAUniversité et INSA de RouenSaint Etienne du RouvrayFrance

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