Thermo-Fluid Dynamics of Laser-Irradiated Droplet Using a Fully Coupled Optics-CFD Approach

Thermo-Fluid Dynamics of Laser-Irradiated Droplet Using a Fully Coupled Optics-CFD Approach | 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 Thermo-Fluid Dynamics of Laser-Irradiated Droplet Using a Fully Coupled Optics-CFD Approach Sotiriοs Damianos, Ioannis Karathanassis, Andreas Papoutsakis, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9179403/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 Laser-droplet interactions drive critical advancements across numerous applications, such as bioengineering and nanolithography. While extensive experimental research has been conducted, numerical studies still largely rely on simplified models to capture the complex underlying dynamics. This study investigates the deformation dynamics of a transparent water droplet following its interaction with a laser pulse. Three-dimensional simulations are performed using for the forst time a fully coupled framework that integrates a ray-tracing model, which initialises the laser-induced temperature field, with a GPU-accelerated compressible multiphase flow solver able to handle evaporation, condensation, and shock propagation. The coupled approach demonstrated very good agreement with published experimental results. The ray-tracing model showed that the droplet acts as a lens, focusing rays onto specific points to rapidly increase temperature and initiate explosive evaporation. Sequentially, based on the mass transfer rate, the droplet's hydrodynamic deformation is categorized into three distinct stages. During the primary stage, massive mass transfer rate occurs over a very short duration, where rapid evaporation causes a sharp local pressure rise, generating intense compression shocks and inertial forces that begin stretching the droplet. This transitions into an intermediate stage characterised by a reduced but non-negligible mass transfer rate. Here, propagating shocks reflect as rarefaction waves, leading to the formation of a large cavitation bubble and its subsequent collapse generating secondary shocks. The droplet continues to stretch under decreasing pressure gradients and momentum. In the final stage, mass transfer approaches zero, and residual inertial forces cause the droplet to further stretch, driving it toward complete fragmentation. Physical sciences/Engineering/Mechanical engineering Physical sciences/Engineering/Biomedical engineering Physical sciences/Engineering/Aerospace engineering Full Text Additional Declarations There is NO Competing Interest. 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. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-9179403","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":615368282,"identity":"54eeb25f-f930-4e82-96bd-ad4b7d09c4b3","order_by":0,"name":"Sotiriοs Damianos","email":"data:image/png;base64,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","orcid":"","institution":"City St. George's, University of London","correspondingAuthor":true,"prefix":"","firstName":"Sotiriοs","middleName":"","lastName":"Damianos","suffix":""},{"id":615368283,"identity":"65b86609-ed54-4059-848c-fd57e0823e80","order_by":1,"name":"Ioannis Karathanassis","email":"","orcid":"","institution":"City St. George's, University of London","correspondingAuthor":false,"prefix":"","firstName":"Ioannis","middleName":"","lastName":"Karathanassis","suffix":""},{"id":615368284,"identity":"c30d0ef7-8e8b-4520-b2a5-c798899901b7","order_by":2,"name":"Andreas Papoutsakis","email":"","orcid":"","institution":"University of Hertfordshire","correspondingAuthor":false,"prefix":"","firstName":"Andreas","middleName":"","lastName":"Papoutsakis","suffix":""},{"id":615368285,"identity":"61dfe9b7-9e17-453d-b949-23b432c1d034","order_by":3,"name":"Patrik Vagovic","email":"","orcid":"","institution":"Center for Free-Electron Laser Science, DESY","correspondingAuthor":false,"prefix":"","firstName":"Patrik","middleName":"","lastName":"Vagovic","suffix":""},{"id":615368286,"identity":"72933b73-ec18-4f35-9b0c-16aac9da5b6e","order_by":4,"name":"Claus-Dieter Ohl","email":"","orcid":"https://orcid.org/0000-0001-5333-4723","institution":"Otto-von-Guericke University","correspondingAuthor":false,"prefix":"","firstName":"Claus-Dieter","middleName":"","lastName":"Ohl","suffix":""},{"id":615368287,"identity":"4dea2a0e-6371-4dc9-bd23-7c13331fd891","order_by":5,"name":"Manolis Gavaises","email":"","orcid":"","institution":"City St. George's, University of London","correspondingAuthor":false,"prefix":"","firstName":"Manolis","middleName":"","lastName":"Gavaises","suffix":""}],"badges":[],"createdAt":"2026-03-20 13:30:26","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-9179403/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-9179403/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":108803912,"identity":"41f8bfeb-c5e1-48d8-902d-c6877902d966","added_by":"auto","created_at":"2026-05-08 15:10:42","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1031498,"visible":true,"origin":"","legend":"Article File","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9179403/v1_covered_09bdd9c8-539e-41c6-a646-adbf75b24ebb.pdf"}],"financialInterests":"There is \u003cb\u003eNO\u003c/b\u003e Competing Interest.","formattedTitle":"Thermo-Fluid Dynamics of Laser-Irradiated Droplet Using a Fully Coupled Optics-CFD Approach","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"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":"","lastPublishedDoi":"10.21203/rs.3.rs-9179403/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9179403/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"Laser-droplet interactions drive critical advancements across numerous applications, such as bioengineering and nanolithography. While extensive experimental research has been conducted, numerical studies still largely rely on simplified models to capture the complex underlying dynamics. This study investigates the deformation dynamics of a transparent water droplet following its interaction with a laser pulse. Three-dimensional simulations are performed using for the forst time a fully coupled framework that integrates a ray-tracing model, which initialises the laser-induced temperature field, with a GPU-accelerated compressible multiphase flow solver able to handle evaporation, condensation, and shock propagation. The coupled approach demonstrated very good agreement with published experimental results. The ray-tracing model showed that the droplet acts as a lens, focusing rays onto specific points to rapidly increase temperature and initiate explosive evaporation.\r\nSequentially, based on the mass transfer rate, the droplet's hydrodynamic deformation is categorized into three distinct stages.\r\nDuring the primary stage, massive mass transfer rate occurs over a very short duration, where rapid evaporation causes a sharp local pressure rise, generating intense compression shocks and inertial forces that begin stretching the droplet. This transitions into an intermediate stage characterised by a reduced but non-negligible mass transfer rate. Here, propagating shocks reflect as rarefaction waves, leading to the formation of a large cavitation bubble and its subsequent collapse generating secondary shocks. The droplet continues to stretch under decreasing pressure gradients and momentum. In the final stage, mass transfer approaches zero, and residual inertial forces cause the droplet to further stretch, driving it toward complete fragmentation.","manuscriptTitle":"Thermo-Fluid Dynamics of Laser-Irradiated Droplet Using a Fully Coupled Optics-CFD Approach","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-04-02 02:59:51","doi":"10.21203/rs.3.rs-9179403/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","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}}],"origin":"","ownerIdentity":"d90b0270-12f6-4056-9d43-65446c86e33d","owner":[],"postedDate":"April 2nd, 2026","published":true,"recentEditorialEvents":[{"type":"decision","content":"Reject after peer review","date":"2026-05-05T13:41:48+00:00","index":"","fulltext":""}],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":65477771,"name":"Physical sciences/Engineering/Mechanical engineering"},{"id":65477772,"name":"Physical sciences/Engineering/Biomedical engineering"},{"id":65477773,"name":"Physical sciences/Engineering/Aerospace engineering"}],"tags":[],"updatedAt":"2026-05-05T13:45:57+00:00","versionOfRecord":[],"versionCreatedAt":"2026-04-02 02:59:51","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9179403","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9179403","identity":"rs-9179403","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}