Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Videos

Flocs in Shear and Strain Flows.

Stefan Blaser1

  • 1Institute of Hydromechanics and Water Resources Management, Swiss Federal Institute of Technology, Zürich, CH-8093, Switzerland

Journal of Colloid and Interface Science
|March 20, 2001
PubMed
Summary

Ferric hydroxide flocs behave like solid ellipsoids in simple shear flow, rotating with the fluid. In extensional flow, these flocs rupture along the straining axis, revealing their mechanical properties.

Related Concept Videos

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Multiple forest attributes underpin the supply of multiple ecosystem services.

Nature communications·2018
Same author

Land-use intensification causes multitrophic homogenization of grassland communities.

Nature·2016
Same author

Biodiversity at multiple trophic levels is needed for ecosystem multifunctionality.

Nature·2016
Same author

Locally rare species influence grassland ecosystem multifunctionality.

Philosophical transactions of the Royal Society of London. Series B, Biological sciences·2016
Same author

Land use intensification alters ecosystem multifunctionality via loss of biodiversity and changes to functional composition.

Ecology letters·2015
Same author

Does land-use intensification decrease plant phylogenetic diversity in local grasslands?

PloS one·2014

Area of Science:

  • Fluid dynamics
  • Colloid science
  • Materials science

Background:

  • Understanding floc behavior in fluid flow is crucial for water treatment and industrial processes.
  • Ferric hydroxide flocs are common in water purification.

Purpose of the Study:

  • To investigate the dynamic response and rupture of ferric hydroxide flocs under different flow conditions.
  • To characterize floc deformation and failure mechanisms.

Main Methods:

  • Optical observation of preflocculated ferric hydroxide flocs.
  • Digital image analysis to track floc orientation and deformation.
  • Application of simple shear flow and two-dimensional straining flow.

Main Results:

  • Flocs exhibited rotational motion in simple shear flow, consistent with solid ellipsoid behavior.
  • In extensional flow, flocs did not rotate continuously but fractured along the straining axis.
  • Estimated rupture forces were approximately 0.1 N/m².

Conclusions:

  • The rheological behavior of ferric hydroxide flocs can be modeled as solid ellipsoids in shear flow.
  • Extensional flow induces brittle fracture in these flocs.
  • The study provides insights into floc stability and failure under hydrodynamic stress.

Related Experiment Videos