{"id":8336,"date":"2018-04-11T21:16:42","date_gmt":"2018-04-11T21:16:42","guid":{"rendered":"https:\/\/ounews.co\/?p=8336"},"modified":"2018-04-11T21:16:42","modified_gmt":"2018-04-11T21:16:42","slug":"new-snap-evaporation-process-controls-how-liquids-dry","status":"publish","type":"post","link":"https:\/\/www.open.ac.uk\/blogs\/news\/science-mct\/new-snap-evaporation-process-controls-how-liquids-dry\/","title":{"rendered":"New \u2018snap evaporation\u2019 process controls how liquids dry"},"content":{"rendered":"<p>Scientists at The Open University (OU) and Northumbria University have discovered a new process called \u2018snap evaporation\u2019 &#8211; that controls how liquid droplets dry by adjusting their shape and size. This is important because it could affect many everyday tasks, such as minimising watermarks on cars and removing heat from microprocessors within smartphones and computers.<\/p>\n<h3>It&#8217;s hard to control evaporating droplets<\/h3>\n<p>While it seems simple, the research, <a href=\"https:\/\/www.nature.com\/articles\/s41467-018-03840-6\">published today in <em>Nature Communications<\/em><\/a>, explains that until now, controlling evaporating droplets on a solid surface and the way watermarks appear is difficult to predict and control. This is because the shape and location of a droplet as it evaporates is unpredictable. This limits many applications, such as inkjet printing, where an ink droplet can leave a distorted shape on paper, and micro-engineering, where watermarks can spoil the performance of delicate microstructures.<\/p>\n<h3>Discovering the snap evaporation process<\/h3>\n<p>OU Lecturer Dr Marc Pradas explains: \u201cDuring evaporation, the mass of a droplet changes, so this stable drop shape and position becomes unstable. At this \u2018bifurcation\u2019 point, the droplet must change its shape and position. In this study, we were able to control the way droplets dried for the first time, using simple variations on the surface.\u201d<\/p>\n<p>\u201cWe 3D-printed a wavy pattern and covered its rough surface with a thin lubricant layer to create an ultra-smooth surface,\u201d he continues. \u201cThe wavy surface we created acts as a steering wheel, making the droplets \u2018snap\u2019 at specific points, changing their position and shape \u2013 a phenomenon called \u2018snap evaporation\u2019. This guides the droplet to the next stable configuration after a snap has occurred. It\u2019s exciting because it allows us to control the way the droplets dry.\u201d<\/p>\n<p>&nbsp;<\/p>\n<p>Watch this snap evaporation process in action:<\/p>\n<div style=\"width: 1920px;\" class=\"wp-video\"><!--[if lt IE 9]><script>document.createElement('video');<\/script><![endif]-->\n<video class=\"wp-video-shortcode\" id=\"video-8336-1\" width=\"1920\" height=\"1080\" preload=\"metadata\" controls=\"controls\"><source type=\"video\/mp4\" src=\"https:\/\/ounews.co\/wp-content\/uploads\/2018\/04\/Snap_Evaporation_logos-1.mp4?_=1\" \/><a href=\"https:\/\/ounews.co\/wp-content\/uploads\/2018\/04\/Snap_Evaporation_logos-1.mp4\">https:\/\/ounews.co\/wp-content\/uploads\/2018\/04\/Snap_Evaporation_logos-1.mp4<\/a><\/video><\/div>\n<p>&nbsp;<\/p>\n<h3>It could impact many everyday things<\/h3>\n<p>This research could have an impact on many everyday applications. Snap evaporation could be used to develop self-cleaning and self-sterilising surfaces in hospitals and our homes. The team are working with Jaguar Land Rover to develop new ways to minimise watermarks on the surfaces of cars, and with Sustainable Energy Systems to improve the efficiency of heat-removal systems used in micro-processors. It could be used in microdevices where controlling droplet motion is important, such as\u00a0microchemical reactions, and transporting and mixing fluids.<\/p>\n<h3>And it&#8217;s attracted new research funding<\/h3>\n<p>Dr Pradas is now taking this work to the next level thanks to \u00a3200,000 new funding from the Engineering and Physical Sciences Research Council (EPSRC). In this grant, Dr Pradas will study how surfaces could be designed and used in this process, and how they affect droplet size and motion.<\/p>\n<p><a href=\"http:\/\/www.mathematics.open.ac.uk\/\">Read about the OU\u2019s Maths and Statistics work<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Scientists at The Open University (OU) and Northumbria University have discovered a new process called \u2018snap evaporation\u2019 &#8211; that controls how liquid droplets dry by adjusting their shape and size. This is important because it could affect many everyday tasks, such as minimising watermarks on cars and removing heat from microprocessors within smartphones and computers. [&hellip;]<\/p>\n","protected":false},"author":10,"featured_media":8340,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[29,14],"tags":[734,1328,1392,1783,1904,2042,2115,2391],"class_list":["post-8336","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-maths-statistics","category-science-mct","tag-droplet","tag-liquid","tag-mathematics","tag-process","tag-research","tag-snap-evaporation","tag-stem","tag-watermark"],"_links":{"self":[{"href":"https:\/\/www.open.ac.uk\/blogs\/news\/wp-json\/wp\/v2\/posts\/8336","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.open.ac.uk\/blogs\/news\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.open.ac.uk\/blogs\/news\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.open.ac.uk\/blogs\/news\/wp-json\/wp\/v2\/users\/10"}],"replies":[{"embeddable":true,"href":"https:\/\/www.open.ac.uk\/blogs\/news\/wp-json\/wp\/v2\/comments?post=8336"}],"version-history":[{"count":0,"href":"https:\/\/www.open.ac.uk\/blogs\/news\/wp-json\/wp\/v2\/posts\/8336\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.open.ac.uk\/blogs\/news\/wp-json\/wp\/v2\/media\/8340"}],"wp:attachment":[{"href":"https:\/\/www.open.ac.uk\/blogs\/news\/wp-json\/wp\/v2\/media?parent=8336"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.open.ac.uk\/blogs\/news\/wp-json\/wp\/v2\/categories?post=8336"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.open.ac.uk\/blogs\/news\/wp-json\/wp\/v2\/tags?post=8336"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}