Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Simulations of shearing of capillary bridges
Mid Sweden University, Faculty of Science, Technology and Media, Department of applied science and design.
Mid Sweden University, Faculty of Science, Technology and Media, Department of applied science and design.
2012 (English)In: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 136, no 9, p. Art. no. 094703-Article in journal (Refereed) Published
Abstract [en]

Capillary bridges are considered as the major source of interaction forces acting in wet particulate systems. We study the dynamic shear resistance by using a lattice Boltzmann numerical scheme for a binary fluid. The shear resistance force showed very little dependence on surface tension and contact angle. Instead, the shear resistance is a dynamic phenomenon and a major contributing factor is the distortion of the flow field caused by the presence of interfaces. This distortion of the flow field is geometry-dependent: in smaller diameter bridges the proportion of this distorted flow field becomes larger and it makes a major contribution to the shear resistance force. In other words multiple bridges have an enhancement effect on shear resistance.

Place, publisher, year, edition, pages
2012. Vol. 136, no 9, p. Art. no. 094703-
Keywords [en]
Binary fluids; Contributing factor; Dynamic phenomena; Enhancement effects; Interaction forces; Lattice boltzmann; Numerical scheme; Particulate systems; Shear resistance forces; Shear resistances
National Category
Atom and Molecular Physics and Optics
Identifiers
URN: urn:nbn:se:miun:diva-16469DOI: 10.1063/1.3689293ISI: 000301664200043PubMedID: 22401464Scopus ID: 2-s2.0-84858212377OAI: oai:DiVA.org:miun-16469DiVA, id: diva2:534246
Available from: 2012-06-15 Created: 2012-06-15 Last updated: 2017-12-07Bibliographically approved
In thesis
1. Lattice Boltzmann simulations of two-phased flow in fibre network systems
Open this publication in new window or tab >>Lattice Boltzmann simulations of two-phased flow in fibre network systems
2012 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Two-phase flow in microfluidic systems is of great interest for many scientificand engineering problems. Especially in the pulp and paper area, the problems spanfrom fibre-fibre interactions in the consolidation process of papermaking to edgewickingin paper board during the aseptic treatment of liquid packaging.The objective of this thesis is to gain a fundamental understanding of the microfluidicmechanisms that play a significant role in various problems of two-phaseflow in fibre networks. To achieve this objective a new method for the treatment ofwetting boundary conditions in the lattice Boltzmann model has been developed.The model was validated and compared with the previous treatments of wettingboundary conditions, by using two test cases: droplet spreading and capillary intrusion.The new wetting boundary condition was shown to give more accurate resultsfor a wider range of contact angles than previous methods, and capillary intrusioncould be simulated with higher accuracy even at a relatively low resolution.As an application of the developed method, two examples of two-phase flowproblems in fibre networks are taken: the shear resistance of liquid bridges, as relatedto the wet web strength, and liquid penetration into porous structures, as related toedge-wicking in paper board. The shear resistance force was shown to depend verylittle on surface tension and contact angle. Instead, the shear resistance is a dynamicforce and a major contributing factor is the distortion of the flow field caused bythe presence of interfaces. This distortion of the flow field is size-dependent: thesmaller the bridge, the larger the proportion of the distorted flow field and thus alarger shear resistance force per unit width. In other words, multiple small bridgeshave an enhancement effect on shear resistance. The results from the simulations ofliquid penetration into porous structures showed that the discontinuities in the solidsurfacecurvature, as are present in the formof corners on the capillary surfaces, havestrong influences on liquid penetration through their pinning effects and also theirinteractions with local geometry. The microtopography can therefore, accelerate,decelerate and, in some cases, even stop the liquid penetration into random porousmedia.

Place, publisher, year, edition, pages
Sundsvall: Mid Sweden University, 2012. p. 43
Series
Mid Sweden University doctoral thesis, ISSN 1652-893X ; 130
National Category
Paper, Pulp and Fiber Technology
Identifiers
urn:nbn:se:miun:diva-16475 (URN)978-91-87103-23-0 (ISBN)
Supervisors
Available from: 2012-06-15 Created: 2012-06-15 Last updated: 2012-11-21Bibliographically approved

Open Access in DiVA

No full text in DiVA

Other links

Publisher's full textPubMedScopus

Search in DiVA

By author/editor
Wiklund, HannaUesaka, Tetsu
By organisation
Department of applied science and design
In the same journal
Journal of Chemical Physics
Atom and Molecular Physics and Optics

Search outside of DiVA

GoogleGoogle Scholar

doi
pubmed
urn-nbn

Altmetric score

doi
pubmed
urn-nbn
Total: 991 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf