Dancing Vapor Clouds Above Evaporating Sessile Droplets: Results of 78th ESA Parabolic Flight Campaign

Dancing Vapor Clouds Above Evaporating Sessile Droplets: Results of 78th ESA Parabolic Flight Campaign | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Dancing Vapor Clouds Above Evaporating Sessile Droplets: Results of 78 th ESA Parabolic Flight Campaign Senthil Kumar Parimalanathan, Hatim Machrafi, Adam Chafai, Alexey Rednikov, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6631590/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract As a series of microgravity tests before a forthcoming space experiment aboard the International Space Station, evaporation of a sessile droplet of a pure liquid (here a refrigerant HFE-7100) into a quiescent nitrogen atmosphere has been studied in a parabolic flight campaign. The ambient conditions were those of the aircraft (19.5°C and 850 mbar, somewhat below the normal conditions), the contact line was pinned at a circular microgroove of a radius of 2 mm in the substrate, and droplet volumes ranged between about 6 µL and 10 µL (contact angles from 45° to 70°). Despite some anomalies in the injection system, also encountered in previous experiments, we eventually estimated evaporation rates by observing droplet volume changes with a side-view camera. A noticeable influence of residual gravity fluctuations in the plane ('g-jitter', up to 10-2g here) was revealed, especially for negative-g periods, rendering the present experiment not exactly 0g. Even if the roughness of volume data differentiation with time did not permit to follow the evaporation rate fluctuations in response to the g-jitter and only averaged values were actually measured, this gap was bridged by vapor interferometry and numerical simulations. In particular, 'dancing' vapor clouds were thereby revealed, which turned out to be in a good agreement with simulations. The role of an intense thermal Marangoni circulation inside the droplet under g-jitter conditions was also explored in simulations. Physical sciences/Physics/Fluid dynamics Physical sciences/Optics and photonics/Optical techniques Physical sciences/Mathematics and computing Physical sciences/Physics/Condensed matter physics/Surfaces interfaces and thin films Evaporation interferometry sessile droplet parabolic flight g-jitter CFD Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6631590","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":459343892,"identity":"3d895a97-40d0-41d0-bc77-cf461e694ca8","order_by":0,"name":"Senthil Kumar Parimalanathan","email":"data:image/png;base64,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","orcid":"","institution":"Université Libre de Bruxelles","correspondingAuthor":true,"prefix":"","firstName":"Senthil","middleName":"Kumar","lastName":"Parimalanathan","suffix":""},{"id":459343894,"identity":"4cf6eaeb-c619-4398-b0bc-6579b1a5d68a","order_by":1,"name":"Hatim Machrafi","email":"","orcid":"","institution":"University of Liège","correspondingAuthor":false,"prefix":"","firstName":"Hatim","middleName":"","lastName":"Machrafi","suffix":""},{"id":459343896,"identity":"22417d4b-fd79-4f24-83b4-09833af15cd7","order_by":2,"name":"Adam Chafai","email":"","orcid":"","institution":"Université Libre de Bruxelles","correspondingAuthor":false,"prefix":"","firstName":"Adam","middleName":"","lastName":"Chafai","suffix":""},{"id":459343902,"identity":"45341629-fe95-4f2b-8d22-d0fa195228f5","order_by":3,"name":"Alexey Rednikov","email":"","orcid":"","institution":"Université Libre de Bruxelles","correspondingAuthor":false,"prefix":"","firstName":"Alexey","middleName":"","lastName":"Rednikov","suffix":""},{"id":459343903,"identity":"617c7709-f2b9-40c1-9f19-e9f76418e9c7","order_by":4,"name":"Pierre Colinet","email":"","orcid":"","institution":"Université Libre de Bruxelles","correspondingAuthor":false,"prefix":"","firstName":"Pierre","middleName":"","lastName":"Colinet","suffix":""}],"badges":[],"createdAt":"2025-05-09 22:53:12","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6631590/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6631590/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":85626954,"identity":"2d87558c-755e-4341-adda-c82251c99a69","added_by":"auto","created_at":"2025-06-30 00:16:30","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":9014170,"visible":true,"origin":"","legend":"","description":"","filename":"ARTICLE.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6631590/v1_covered_eea9720b-0245-4fcd-bd87-caa3ca43afa9.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"\u003cp\u003eDancing Vapor Clouds Above Evaporating Sessile Droplets: Results of 78\u003csup\u003eth\u003c/sup\u003e ESA Parabolic Flight Campaign \u003c/p\u003e","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Evaporation, interferometry, sessile droplet, parabolic flight, g-jitter, CFD","lastPublishedDoi":"10.21203/rs.3.rs-6631590/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6631590/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eAs a series of microgravity tests before a forthcoming space experiment aboard the International Space Station, evaporation of a sessile droplet of a pure liquid (here a refrigerant HFE-7100) into a quiescent nitrogen atmosphere has been studied in a parabolic flight campaign. 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