{"id":3990,"date":"2009-03-14T10:47:00","date_gmt":"2009-03-14T10:47:00","guid":{"rendered":"http:\/\/thales.mit.edu\/bush\/?p=3990"},"modified":"2021-04-15T01:23:01","modified_gmt":"2021-04-15T01:23:01","slug":"drop-propulsion-in-tapered-tubes","status":"publish","type":"post","link":"http:\/\/thales.mit.edu\/bush\/index.php\/2009\/03\/14\/drop-propulsion-in-tapered-tubes\/","title":{"rendered":"Drop propulsion in tapered tubes"},"content":{"rendered":"\n<div class=\"wp-block-cover has-subtle-background-color has-background-dim\"><div class=\"wp-block-cover__inner-container is-layout-flow wp-block-cover-is-layout-flow\">\n<div class=\"wp-block-image\"><figure class=\"alignright size-large is-resized\"><img loading=\"lazy\" decoding=\"async\" src=\"http:\/\/thales.mit.edu\/bush\/wp-content\/uploads\/2021\/04\/Tapered.png\" alt=\"\" class=\"wp-image-6383\" width=\"493\" height=\"306\"\/><\/figure><\/div>\n\n\n\n<p>We present the results of a combined experimental and theoretical investigation of the motion of wetting droplets in tapered capillary tubes. We demonstrate that drops may move spontaneously towards the tapered end owing to the Laplace pressure gradient established along their length. The influence of gravity on this spontaneous motion is examined by studying drop motion along a tilted tube with its tapered end pointing upwards. Provided the tube taper varies, an equilibrium height may be achieved in which the capillary force is balanced by the drop\u2019s weight. We deduce the family of tube shapes that support a stable equilibrium.<\/p>\n\n\n\n<p>See paper: &nbsp;<a href=\"http:\/\/math.mit.edu\/~bush\/wordpress\/wp-content\/uploads\/2012\/09\/EPL_Renvoise.pdf\">Renvoise, Bush, Prakash &amp; Quere (2009)<\/a>.<\/p>\n<\/div><\/div>\n","protected":false},"excerpt":{"rendered":"","protected":false},"author":5,"featured_media":3991,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6],"tags":[],"class_list":["post-3990","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-interfacial-flows","entry"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v16.3 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>Drop propulsion in tapered tubes - John W. M. Bush<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"http:\/\/thales.mit.edu\/bush\/index.php\/2009\/03\/14\/drop-propulsion-in-tapered-tubes\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Drop propulsion in tapered tubes - John W. M. Bush\" \/>\n<meta property=\"og:url\" content=\"http:\/\/thales.mit.edu\/bush\/index.php\/2009\/03\/14\/drop-propulsion-in-tapered-tubes\/\" \/>\n<meta property=\"og:site_name\" content=\"John W. M. Bush\" \/>\n<meta property=\"article:published_time\" content=\"2009-03-14T10:47:00+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2021-04-15T01:23:01+00:00\" \/>\n<meta property=\"og:image\" content=\"http:\/\/thales.mit.edu\/bush\/wp-content\/uploads\/2021\/03\/tube.jpg\" \/>\n\t<meta property=\"og:image:width\" content=\"400\" \/>\n\t<meta property=\"og:image:height\" content=\"252\" \/>\n<meta name=\"twitter:card\" content=\"summary\" \/>\n<meta name=\"twitter:label1\" content=\"Est. reading time\">\n\t<meta name=\"twitter:data1\" content=\"1 minute\">\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"WebSite\",\"@id\":\"https:\/\/thales.mit.edu\/bush\/#website\",\"url\":\"https:\/\/thales.mit.edu\/bush\/\",\"name\":\"John W. M. 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