Skip to main navigation Skip to search Skip to main content

Changes in fractal dimension during aggregation

  • Rajat K. Chakraborti
  • , Kevin H. Gardner
  • , Joseph F. Atkinson
  • , John E. Van Benschoten
  • SUNY Buffalo

Research output: Contribution to journalArticlepeer-review

283 Scopus citations

Abstract

Experiments were performed to evaluate temporal changes in the fractal dimension of aggregates formed during flocculation of an initially monodisperse suspension of latex microspheres. Particle size distributions and aggregate geometrical information at different mixing times were obtained using a non-intrusive optical sampling and digital image analysis technique, under variable conditions of mixing speed, coagulant (alum) dose and particle concentration. Pixel resolution required to determine aggregate size and geometric measures including the fractal dimension is discussed and a quantitative measure of accuracy is developed. The two-dimensional fractal dimension was found to range from 1.94 to 1.48, corresponding to aggregates that are either relatively compact or loosely structured, respectively. Changes in fractal dimension are explained using a conceptual model, which describes changes in fractal dimension associated with aggregate growth and changes in aggregate structure. For aggregation of an initially monodisperse suspension, the fractal dimension was found to decrease over time in the initial stages of floc formation.

Original languageEnglish
Pages (from-to)873-883
Number of pages11
JournalWater Research
Volume37
Issue number4
DOIs
StatePublished - Feb 2003

Keywords

  • Alum
  • Coagulation-flocculation
  • Fractal dimension
  • Image analysis
  • Particle size distribution
  • Pixel resolution
  • Shear rate

Fingerprint

Dive into the research topics of 'Changes in fractal dimension during aggregation'. Together they form a unique fingerprint.

Cite this