Formation and pinch-off of leading vortex ring in starting jets with uniform background crossflow

Formation and pinch-off of leading vortex ring in starting jets with uniform background crossflow | 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 Research Article Formation and pinch-off of leading vortex ring in starting jets with uniform background crossflow Ruijia Zhao, Guoqing Zhang, Jianwei Zhu, S.C.M. Yu This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4615955/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 The formation and pinch-off of leading vortex ring in the starting jets with uniform background crossflow have been investigated numerically for Rv from 3 to 12and ∞,where Rv is the ratio of the jet velocity Uj to the velocity of background crossflow Uc. Rv = ∞ represents the case without any background crossflow. The background crossflow disrupts the symmetry in the formation process of leading vortex ring, causing it to move laterally and the circulation strength on either side of it to be unequal. The difference in the circulation strength can be normalized based on slug model. The lateral movement introduced by crossflow is found to be inversely proportional to Rv,but directly proportional to Uc at aconstant Uj. A kinematic model based on the lateral movement of leading vortex ring is established to characterize the pinch-off process in the starting jet with background crossflow. The occurrence of pinch-off at Rv ≥ 12 remains consistent with that without background crossflow, i.e., the formation number F remains constant with Rv. As for smaller Rv (less than 12), F increases linearly with Rv,i.e., F ∼ C2Rv,where C2 is a constant. Starting Jet Background Crossflow Pinch-off Vortex Ring 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. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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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-4615955","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":320677653,"identity":"26e04290-d7be-40b5-a562-18a602c6af65","order_by":0,"name":"Ruijia Zhao","email":"","orcid":"","institution":"Beijing Institute of Technology","correspondingAuthor":false,"prefix":"","firstName":"Ruijia","middleName":"","lastName":"Zhao","suffix":""},{"id":320677654,"identity":"5bf87218-695b-4fd6-8b98-c7ff6319a733","order_by":1,"name":"Guoqing Zhang","email":"","orcid":"","institution":"Beijing Institute of Technology","correspondingAuthor":false,"prefix":"","firstName":"Guoqing","middleName":"","lastName":"Zhang","suffix":""},{"id":320677656,"identity":"7a9670e5-8810-4891-8c0e-7c41dea3343a","order_by":2,"name":"Jianwei Zhu","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA3UlEQVRIiWNgGAWjYBACNvbmAwcSDGrq7ec/PvggoaKGsBY+nmOJDx4UHEswYEhLNnhw5hhhLXISOcaGDz4wA7XkmEk+bGEmwmE8x9IkEgzY8swZjqVVJDawMfC3dycQ8ssxoBaZYsvG5mM3EnfIMEicObuBKFsYGw6zpd1IPMPGYCCRS0CLRI4ZUAszY8MxHrOCxDZmorQYGwC1JG44w2PGQJwWUCAnGBwzlpzBliyRcOYYD0G/yLc3Hzj440+NHL8E88GPPyqAjPZe/FowAA9pykfBKBgFo2AUYAUAC+5MiGtWLXgAAAAASUVORK5CYII=","orcid":"","institution":"Beijing Institute of Technology","correspondingAuthor":true,"prefix":"","firstName":"Jianwei","middleName":"","lastName":"Zhu","suffix":""},{"id":320677660,"identity":"4e3d5eff-74a7-4530-8a4d-213f1eb41d46","order_by":3,"name":"S.C.M. 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