No Cover Image

Journal article 1039 views 364 downloads

Investigating the causes of shear-thinning in non-colloidal suspensions: Experiments and simulations

Adolfo Vázquez-Quesada, Arif Mahmud, Shaocong Dai, Marco Ellero, Roger I. Tanner, Adolfo Vazquez-Quesada

Journal of Non-Newtonian Fluid Mechanics, Volume: 248, Pages: 1 - 7

Swansea University Authors: Marco Ellero, Adolfo Vazquez-Quesada

Check full text

DOI (Published version): 10.1016/j.jnnfm.2017.08.005

Abstract

Experiments and computations were carried out to explore the origins of shear-thinning in non-colloidal suspensions. Two grades of polydimethylsiloxane (silicone oil) and a glycerine/water mixture were used as matrices for the suspensions. The particles were 40μm diameter polystyrene (PS) and polyme...

Full description

Published in: Journal of Non-Newtonian Fluid Mechanics
ISSN: 0377-0257
Published: 2017
Online Access: Check full text

URI: https://cronfa.swan.ac.uk/Record/cronfa35008
Tags: Add Tag
No Tags, Be the first to tag this record!
first_indexed 2017-08-24T18:42:56Z
last_indexed 2020-06-01T18:46:53Z
id cronfa35008
recordtype SURis
fullrecord <?xml version="1.0"?><rfc1807><datestamp>2020-06-01T16:30:09.8415680</datestamp><bib-version>v2</bib-version><id>35008</id><entry>2017-08-24</entry><title>Investigating the causes of shear-thinning in non-colloidal suspensions: Experiments and simulations</title><swanseaauthors><author><sid>84f2af0791d38bdbf826728de7e5c69d</sid><firstname>Marco</firstname><surname>Ellero</surname><name>Marco Ellero</name><active>true</active><ethesisStudent>false</ethesisStudent></author><author><sid>14cfebea6166c6de4a9764b6e98e794c</sid><firstname>Adolfo</firstname><surname>Vazquez-Quesada</surname><name>Adolfo Vazquez-Quesada</name><active>true</active><ethesisStudent>false</ethesisStudent></author></swanseaauthors><date>2017-08-24</date><deptcode>FGSEN</deptcode><abstract>Experiments and computations were carried out to explore the origins of shear-thinning in non-colloidal suspensions. Two grades of polydimethylsiloxane (silicone oil) and a glycerine/water mixture were used as matrices for the suspensions. The particles were 40&#x3BC;m diameter polystyrene (PS) and polymethyl methacrylate (PMMA) spheres. We concentrated on 40% volume fraction suspensions where shear-thinning was clear. The silicone oil matrices were nearly Newtonian: at 24o C the viscosity of the 1.15Pa-s sample showed a 2% drop in viscosity a shear rate of about 3000s&#x2212;1, the 13.2 Pa-s sample showed a drop of 2% at a shear rate of approximately 100s&#x2212;1, and the glycerine/water sample appeared to be Newtonian at least up to 104 s&#x2212;1. Mild shear-thinning was seen with all suspensions, beginning at shear rates of order 0.1-1 s&#x2212;1, followed by a rapid reduction of torque in the parallel-plate system at shear rates of 14, 150 and 1000s&#x2212;1 respectively with the three matrices. These rapid reductions are ascribed to edge effects.Matching smoothed particle hydrodynamics (SPH) simulations were made. The silicone matrix viscosities were modelled by a Carreau-Yasuda (CY) fit up to shear rates of order 107 s&#x2212;1. The agreement between computations and experiments is generally good for 40% volume fraction suspensions up to the shear rate where edge effects intervene in the experiments- there are no edge effects in the simulations. This confirms the suggestion [1] by V&#xE1;zquez-Quesada et al [Phys. Rev. Lett,117, 108001 (2017)] that &#x2018;hidden&#x2019; high shear rates between particles, where the non-Newtonian matrix viscosity comes into play, can result in shear-thinning at the macroscopic level. For the glycerine/water matrix at low shear rates this mechanism does not apply and a separate mechanism based on variable interparticle friction is suggested; the two mechanisms can co-exist.</abstract><type>Journal Article</type><journal>Journal of Non-Newtonian Fluid Mechanics</journal><volume>248</volume><paginationStart>1</paginationStart><paginationEnd>7</paginationEnd><publisher/><issnPrint>0377-0257</issnPrint><keywords/><publishedDay>31</publishedDay><publishedMonth>10</publishedMonth><publishedYear>2017</publishedYear><publishedDate>2017-10-31</publishedDate><doi>10.1016/j.jnnfm.2017.08.005</doi><url/><notes/><college>COLLEGE NANME</college><department>Science and Engineering - Faculty</department><CollegeCode>COLLEGE CODE</CollegeCode><DepartmentCode>FGSEN</DepartmentCode><institution>Swansea University</institution><apcterm/><lastEdited>2020-06-01T16:30:09.8415680</lastEdited><Created>2017-08-24T13:53:53.8954185</Created><path><level id="1">Faculty of Science and Engineering</level><level id="2">School of Engineering and Applied Sciences - Uncategorised</level></path><authors><author><firstname>Adolfo</firstname><surname>V&#xE1;zquez-Quesada</surname><order>1</order></author><author><firstname>Arif</firstname><surname>Mahmud</surname><order>2</order></author><author><firstname>Shaocong</firstname><surname>Dai</surname><order>3</order></author><author><firstname>Marco</firstname><surname>Ellero</surname><order>4</order></author><author><firstname>Roger I.</firstname><surname>Tanner</surname><order>5</order></author><author><firstname>Adolfo</firstname><surname>Vazquez-Quesada</surname><order>6</order></author></authors><documents><document><filename>0035008-24082017135704.pdf</filename><originalFilename>vzquez-quesada2017.pdf</originalFilename><uploaded>2017-08-24T13:57:04.6070000</uploaded><type>Output</type><contentLength>1181888</contentLength><contentType>application/pdf</contentType><version>Accepted Manuscript</version><cronfaStatus>true</cronfaStatus><embargoDate>2018-08-24T00:00:00.0000000</embargoDate><copyrightCorrect>true</copyrightCorrect><language>eng</language></document></documents><OutputDurs/></rfc1807>
spelling 2020-06-01T16:30:09.8415680 v2 35008 2017-08-24 Investigating the causes of shear-thinning in non-colloidal suspensions: Experiments and simulations 84f2af0791d38bdbf826728de7e5c69d Marco Ellero Marco Ellero true false 14cfebea6166c6de4a9764b6e98e794c Adolfo Vazquez-Quesada Adolfo Vazquez-Quesada true false 2017-08-24 FGSEN Experiments and computations were carried out to explore the origins of shear-thinning in non-colloidal suspensions. Two grades of polydimethylsiloxane (silicone oil) and a glycerine/water mixture were used as matrices for the suspensions. The particles were 40μm diameter polystyrene (PS) and polymethyl methacrylate (PMMA) spheres. We concentrated on 40% volume fraction suspensions where shear-thinning was clear. The silicone oil matrices were nearly Newtonian: at 24o C the viscosity of the 1.15Pa-s sample showed a 2% drop in viscosity a shear rate of about 3000s−1, the 13.2 Pa-s sample showed a drop of 2% at a shear rate of approximately 100s−1, and the glycerine/water sample appeared to be Newtonian at least up to 104 s−1. Mild shear-thinning was seen with all suspensions, beginning at shear rates of order 0.1-1 s−1, followed by a rapid reduction of torque in the parallel-plate system at shear rates of 14, 150 and 1000s−1 respectively with the three matrices. These rapid reductions are ascribed to edge effects.Matching smoothed particle hydrodynamics (SPH) simulations were made. The silicone matrix viscosities were modelled by a Carreau-Yasuda (CY) fit up to shear rates of order 107 s−1. The agreement between computations and experiments is generally good for 40% volume fraction suspensions up to the shear rate where edge effects intervene in the experiments- there are no edge effects in the simulations. This confirms the suggestion [1] by Vázquez-Quesada et al [Phys. Rev. Lett,117, 108001 (2017)] that ‘hidden’ high shear rates between particles, where the non-Newtonian matrix viscosity comes into play, can result in shear-thinning at the macroscopic level. For the glycerine/water matrix at low shear rates this mechanism does not apply and a separate mechanism based on variable interparticle friction is suggested; the two mechanisms can co-exist. Journal Article Journal of Non-Newtonian Fluid Mechanics 248 1 7 0377-0257 31 10 2017 2017-10-31 10.1016/j.jnnfm.2017.08.005 COLLEGE NANME Science and Engineering - Faculty COLLEGE CODE FGSEN Swansea University 2020-06-01T16:30:09.8415680 2017-08-24T13:53:53.8954185 Faculty of Science and Engineering School of Engineering and Applied Sciences - Uncategorised Adolfo Vázquez-Quesada 1 Arif Mahmud 2 Shaocong Dai 3 Marco Ellero 4 Roger I. Tanner 5 Adolfo Vazquez-Quesada 6 0035008-24082017135704.pdf vzquez-quesada2017.pdf 2017-08-24T13:57:04.6070000 Output 1181888 application/pdf Accepted Manuscript true 2018-08-24T00:00:00.0000000 true eng
title Investigating the causes of shear-thinning in non-colloidal suspensions: Experiments and simulations
spellingShingle Investigating the causes of shear-thinning in non-colloidal suspensions: Experiments and simulations
Marco Ellero
Adolfo Vazquez-Quesada
title_short Investigating the causes of shear-thinning in non-colloidal suspensions: Experiments and simulations
title_full Investigating the causes of shear-thinning in non-colloidal suspensions: Experiments and simulations
title_fullStr Investigating the causes of shear-thinning in non-colloidal suspensions: Experiments and simulations
title_full_unstemmed Investigating the causes of shear-thinning in non-colloidal suspensions: Experiments and simulations
title_sort Investigating the causes of shear-thinning in non-colloidal suspensions: Experiments and simulations
author_id_str_mv 84f2af0791d38bdbf826728de7e5c69d
14cfebea6166c6de4a9764b6e98e794c
author_id_fullname_str_mv 84f2af0791d38bdbf826728de7e5c69d_***_Marco Ellero
14cfebea6166c6de4a9764b6e98e794c_***_Adolfo Vazquez-Quesada
author Marco Ellero
Adolfo Vazquez-Quesada
author2 Adolfo Vázquez-Quesada
Arif Mahmud
Shaocong Dai
Marco Ellero
Roger I. Tanner
Adolfo Vazquez-Quesada
format Journal article
container_title Journal of Non-Newtonian Fluid Mechanics
container_volume 248
container_start_page 1
publishDate 2017
institution Swansea University
issn 0377-0257
doi_str_mv 10.1016/j.jnnfm.2017.08.005
college_str Faculty of Science and Engineering
hierarchytype
hierarchy_top_id facultyofscienceandengineering
hierarchy_top_title Faculty of Science and Engineering
hierarchy_parent_id facultyofscienceandengineering
hierarchy_parent_title Faculty of Science and Engineering
department_str School of Engineering and Applied Sciences - Uncategorised{{{_:::_}}}Faculty of Science and Engineering{{{_:::_}}}School of Engineering and Applied Sciences - Uncategorised
document_store_str 1
active_str 0
description Experiments and computations were carried out to explore the origins of shear-thinning in non-colloidal suspensions. Two grades of polydimethylsiloxane (silicone oil) and a glycerine/water mixture were used as matrices for the suspensions. The particles were 40μm diameter polystyrene (PS) and polymethyl methacrylate (PMMA) spheres. We concentrated on 40% volume fraction suspensions where shear-thinning was clear. The silicone oil matrices were nearly Newtonian: at 24o C the viscosity of the 1.15Pa-s sample showed a 2% drop in viscosity a shear rate of about 3000s−1, the 13.2 Pa-s sample showed a drop of 2% at a shear rate of approximately 100s−1, and the glycerine/water sample appeared to be Newtonian at least up to 104 s−1. Mild shear-thinning was seen with all suspensions, beginning at shear rates of order 0.1-1 s−1, followed by a rapid reduction of torque in the parallel-plate system at shear rates of 14, 150 and 1000s−1 respectively with the three matrices. These rapid reductions are ascribed to edge effects.Matching smoothed particle hydrodynamics (SPH) simulations were made. The silicone matrix viscosities were modelled by a Carreau-Yasuda (CY) fit up to shear rates of order 107 s−1. The agreement between computations and experiments is generally good for 40% volume fraction suspensions up to the shear rate where edge effects intervene in the experiments- there are no edge effects in the simulations. This confirms the suggestion [1] by Vázquez-Quesada et al [Phys. Rev. Lett,117, 108001 (2017)] that ‘hidden’ high shear rates between particles, where the non-Newtonian matrix viscosity comes into play, can result in shear-thinning at the macroscopic level. For the glycerine/water matrix at low shear rates this mechanism does not apply and a separate mechanism based on variable interparticle friction is suggested; the two mechanisms can co-exist.
published_date 2017-10-31T03:43:27Z
_version_ 1763752025317703680
score 11.035655

Similar Items