{"id":38,"date":"2016-02-17T16:39:01","date_gmt":"2016-02-18T00:39:01","guid":{"rendered":"http:\/\/research.engineering.ucdavis.edu\/phillips\/?page_id=38"},"modified":"2016-02-18T11:16:28","modified_gmt":"2016-02-18T19:16:28","slug":"sedimentation-instability-2","status":"publish","type":"page","link":"https:\/\/research.engineering.ucdavis.edu\/phillips\/sample-page\/sedimentation-instability-2\/","title":{"rendered":"Sedimentation instability"},"content":{"rendered":"<p>When suspensions sediment through viscoelastic fluids, a structural instability occurs in which the particles order themselves into particle-rich and particle-depleted regions.\u00a0 This change causes a dramatic change in the\u00a0 rate of sedimentation, and is expected to have a comparable effect on the rate of creaming in emulsions.\u00a0 Shown below are images of particles sedimenting 1) through a polyacrylamide solution (above) and 2) through a Newtonian fluid (below).\u00a0 In the Newtonian fluid, the microstructure remains homogeneous and the sedimentation rate is constant.\u00a0 In the viscoelastic fluid, columns form and the sedimentation rate varies continuously.\u00a0 These images were obtained by magnetic resonance imaging (MRI), and are published in the paper by Bobroff and Phillips (1998).\u00a0 Similar behavior has been seen in sedimentation through Xanthan solutions (<i>cf.<\/i> Mora, Talini and Allain, <i>Phys. Rev<\/i>. <i>Lett<\/i>. <b>95<\/b>:088301, 2005)<\/p>\n<p><a href=\"http:\/\/research.engineering.ucdavis.edu\/phillips\/wp-content\/uploads\/sites\/52\/2016\/02\/newtonian.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-medium wp-image-39\" src=\"http:\/\/research.engineering.ucdavis.edu\/phillips\/wp-content\/uploads\/sites\/52\/2016\/02\/newtonian-300x224.jpg\" alt=\"newtonian\" width=\"300\" height=\"224\" srcset=\"https:\/\/research.engineering.ucdavis.edu\/phillips\/wp-content\/uploads\/sites\/52\/2016\/02\/newtonian-300x224.jpg 300w, https:\/\/research.engineering.ucdavis.edu\/phillips\/wp-content\/uploads\/sites\/52\/2016\/02\/newtonian-201x150.jpg 201w, https:\/\/research.engineering.ucdavis.edu\/phillips\/wp-content\/uploads\/sites\/52\/2016\/02\/newtonian-150x112.jpg 150w, https:\/\/research.engineering.ucdavis.edu\/phillips\/wp-content\/uploads\/sites\/52\/2016\/02\/newtonian.jpg 710w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><a href=\"http:\/\/research.engineering.ucdavis.edu\/phillips\/wp-content\/uploads\/sites\/52\/2016\/02\/viscoelastic.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-medium wp-image-40\" src=\"http:\/\/research.engineering.ucdavis.edu\/phillips\/wp-content\/uploads\/sites\/52\/2016\/02\/viscoelastic-300x224.jpg\" alt=\"viscoelastic\" width=\"300\" height=\"224\" srcset=\"https:\/\/research.engineering.ucdavis.edu\/phillips\/wp-content\/uploads\/sites\/52\/2016\/02\/viscoelastic-300x224.jpg 300w, https:\/\/research.engineering.ucdavis.edu\/phillips\/wp-content\/uploads\/sites\/52\/2016\/02\/viscoelastic-201x150.jpg 201w, https:\/\/research.engineering.ucdavis.edu\/phillips\/wp-content\/uploads\/sites\/52\/2016\/02\/viscoelastic-150x112.jpg 150w, https:\/\/research.engineering.ucdavis.edu\/phillips\/wp-content\/uploads\/sites\/52\/2016\/02\/viscoelastic.jpg 710w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><\/p>\n<div><\/div>\n","protected":false},"excerpt":{"rendered":"<p>When suspensions sediment through viscoelastic fluids, a structural instability occurs in which the particles order themselves into particle-rich and particle-depleted regions.\u00a0 This change causes a dramatic change in the\u00a0 rate of sedimentation, and is expected to have a comparable effect on the rate of creaming in emulsions.\u00a0 Shown below are  \u2026 <a href=\"https:\/\/research.engineering.ucdavis.edu\/phillips\/sample-page\/sedimentation-instability-2\/\"> Continue reading <span class=\"meta-nav\">&rarr; <\/span><\/a><\/p>\n","protected":false},"author":90,"featured_media":0,"parent":2,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-38","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/research.engineering.ucdavis.edu\/phillips\/wp-json\/wp\/v2\/pages\/38","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/research.engineering.ucdavis.edu\/phillips\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/research.engineering.ucdavis.edu\/phillips\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/research.engineering.ucdavis.edu\/phillips\/wp-json\/wp\/v2\/users\/90"}],"replies":[{"embeddable":true,"href":"https:\/\/research.engineering.ucdavis.edu\/phillips\/wp-json\/wp\/v2\/comments?post=38"}],"version-history":[{"count":1,"href":"https:\/\/research.engineering.ucdavis.edu\/phillips\/wp-json\/wp\/v2\/pages\/38\/revisions"}],"predecessor-version":[{"id":41,"href":"https:\/\/research.engineering.ucdavis.edu\/phillips\/wp-json\/wp\/v2\/pages\/38\/revisions\/41"}],"up":[{"embeddable":true,"href":"https:\/\/research.engineering.ucdavis.edu\/phillips\/wp-json\/wp\/v2\/pages\/2"}],"wp:attachment":[{"href":"https:\/\/research.engineering.ucdavis.edu\/phillips\/wp-json\/wp\/v2\/media?parent=38"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}