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Experiments in Fluids

, 58:100 | Cite as

Sizing of sand and ash particles using their speckle pattern: influence of particle opacity

Research Article
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Abstract

A speckle pattern is an interference pattern produced by coherent light scattered from an irregular particle. This pattern is observed in the out-of-focus plane of the particle and it can be used to obtain information about the particle size. When the particle is observed in focus, several bright spots known as glare points are observed on its surface. They correspond to the points from which the light is scattered in the direction of observation. Previous studies using the speckle pattern to obtain the size of irregular particles are based on the hypothesis that the glare points are distributed homogeneously over the whole surface of the particle. The research presented in this paper shows that in the case of opaque particles (such as ash particles), only the areas illuminated by the laser light are covered with glare points. This results in an underestimation of the particle size when characterizing opaque particles using their speckle pattern. In this paper, the speckle pattern is used to perform sizing measurements of translucent and opaque particles, and the results are compared with the ones obtained by image processing of their in-focus images.

Notes

Acknowledgements

The authors acknowledge the financial support of the Agency for Innovation by Science and Technology in Flanders (IWT).

References

  1. Brunel M, Shen H, Coëtmellec S, Gréhan G, Delobel T (2014) Determination of the size of irregular particles using interferometric out-of-focus imaging. Int J Opt. doi: 10.1155/2014/143904 Google Scholar
  2. Brunel M, González Ruiz S, Jacquot J, van Beeck JPAJ (2015) On the morphology of irregular rough particles from the analysis of speckle-like interferometric out-of-focus images. Opt Commun 338:193–198. doi: 10.1016/j.optcom.2014.10.053 CrossRefGoogle Scholar
  3. Brunel M, Lemaitre P, Porcheron E, Coëtmellec S, Gréhan G, Jacquot-Kielar J (2016) Interferometric out-of-focus imaging of ice particles with overlapping images. Appl Opt 55:4902–4909. doi: 10.1155/2014/143904 CrossRefGoogle Scholar
  4. Damaschke N, Nobach H, Nonn TI, Semidetnov N, Tropea C (2005) Multi-dimensional particle sizing techniques. Exp Fluids 39:336–350. doi: 10.1007/s00348-005-1009-1 CrossRefGoogle Scholar
  5. Dehaeck S, van Beeck JPAJ (2007) Designing a maximum precision interferometric particle imaging set-up. Exp Fluids 42:767–781. doi: 10.1007/s00348-007-0286-2 CrossRefGoogle Scholar
  6. García Carrascal P, González Ruiz S, van Beeck JPAJ (2014) Irregular particle sizing using speckle pattern for continuous wave laser applications. Exp Fluids 55:1850–1859. doi: 10.1007/s00348-014-1851-0 CrossRefGoogle Scholar
  7. Glover AR, Skippon SM, Boyle RD (1995) Interferometric laser imaging for droplet sizing: a method for droplet-size measurement in sparse spray systems. Appl Opt 34:8409–8421. doi: 10.1364/AO.34.008409 CrossRefGoogle Scholar
  8. González Ruiz S, Vetrano MR, van Beeck JPAJ (2014) Feasibility of using glory and speckle patterns for sizing spherical and irregular particles. Appl Opt 53:4722–4728. doi: 10.1364/AO.53.004722 CrossRefGoogle Scholar
  9. Hecht E (2002) Optics. Addison Wesley Longman, New YorkGoogle Scholar
  10. König G, Anders K, Frohn A (1986) A new light-scattering technique to measure the diameter of periodically generated moving droplets. J Aerosol Sci 17:157–167. doi: 10.1016/0021-8502(86)90063-7 CrossRefGoogle Scholar
  11. Maeda M, Kawaguchi T, Hishida K (2000) Novel interferometric measurement of size and velocity distributions of spherical particles in fluid flows. Meas Sci Technol 11. doi: 10.1088/0957-0233/11/12/101
  12. van Beeck JPAJ, Riethmuller ML (1996) Rainbow phenomena applied to the measurement of droplet size and velocity and to the detection of nonsphericity. Appl Opt 35:2259–2266. doi: 10.1364/AO.35.002259 CrossRefGoogle Scholar
  13. van de Hulst HC, Wang RT (1991) Glare points. Appl Opt 30:4755–4763. doi: 10.1364/AO.30.004755 CrossRefGoogle Scholar

Copyright information

© Springer-Verlag GmbH Germany 2017

Authors and Affiliations

  1. 1.von Karman Institute for Fluid DynamicsSint-Genesius-RodeBelgium
  2. 2.Vrije Universiteit BrusselBrusselsBelgium

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