Experimental investigation of the evolution of bed topography in an asymmetrical confluence

Experimental investigation of the evolution of bed topography in an asymmetrical confluence | 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 Experimental investigation of the evolution of bed topography in an asymmetrical confluence Gokcen Bombar, António Heleno Cardoso This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4618214/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 04 Jan, 2025 Read the published version in Acta Geophysica → Version 1 posted 6 You are reading this latest preprint version Abstract This study assessed the time evolution of the bed morphology of six experiments performed by Bombar and Cardoso (2020) on mobile bed confluences. These experiments were characterized by a unique junction angle, a fixed plan layout of the converging channels, constant water discharges and water discharge ratio, and six combinations of the converging sediment transport rates. The end aspect ratio of both channels was sufficiently large to avoid strong wall effects, and the flow was always subcritical and rough turbulent. The bed sediment was a uniform non-ripple forming sand. Detail analysis of the time evolution of the bed morphology showed that balanced fluxes of sediments through the boundaries of the system were a sufficient condition of equilibrium within the range of variables covered by the study. The most important morphological features of the confluence were discussed for several time instants, including those referring to the equilibrium phase. The equilibrium features essentially complied with the morpho-dynamic models reported in the literature for mobile bed confluences, meaning that the time evolution and the end (equilibrium) values of the bed morphologies reported in this paper can be used to validate CFD models thought of as predictive tools of confluence morpho-dynamics. Two experiments are, indeed, ideal for this purpose since they converged to static equilibria, and wrong predictions cannot be attributed to oscillations of the bed, whereas those models may only be able to predict the average, equilibrium values of the bed features of experiments run with sediment supply into the main channel and characterized by the movement of bedforms. Confluence Mobile bed Time evolution Morpho-dynamics Sediment transport Full Text Cite Share Download PDF Status: Published Journal Publication published 04 Jan, 2025 Read the published version in Acta Geophysica → Version 1 posted Editorial decision: Major revisions 30 Jul, 2024 Reviewers agreed at journal 29 Jun, 2024 Reviewers invited by journal 29 Jun, 2024 Editor invited by journal 29 Jun, 2024 Editor assigned by journal 26 Jun, 2024 First submitted to journal 22 Jun, 2024 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. 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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-4618214","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":320501260,"identity":"0533b37d-d5f7-4747-b80f-1a975f6e8833","order_by":0,"name":"Gokcen Bombar","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA9ElEQVRIiWNgGAWjYFACNhBxgIFBAkh9qAASzMwNxGthnHEGpIWRBC3MnG0gDgEt8u5tiR8+7rgjpzu7+dlnxnm10fztQC0/Krbh1GJ45thhyZlnnhmb3TlmPLtw2/HcGYcZGxh7ztzGrWVGehszb9vhxG03EoyZZ247ltsA1MLM2EZAy1+wlvTPzLxzjuXOJ6RFXiLtGFABSEuOMTNvQ03uBkJaDHiOJUv2toH8cqaYccaxA7kbgVoO4vOLfHub4YefbXfkzG63b2b4UFOXO+/84YMPflTgseUAKv8wmDyAoQ7ZlgZUfh0+xaNgFIyCUTBCAQCGEGStBU6KHgAAAABJRU5ErkJggg==","orcid":"","institution":"İKÇÜ: Izmir Katip Celebi Universitesi","correspondingAuthor":true,"prefix":"","firstName":"Gokcen","middleName":"","lastName":"Bombar","suffix":""},{"id":320501261,"identity":"57bca94c-062c-46d0-a7cb-77f17642e6ab","order_by":1,"name":"António Heleno Cardoso","email":"","orcid":"","institution":"Universidade de Lisboa Instituto Superior Tecnico","correspondingAuthor":false,"prefix":"","firstName":"António","middleName":"Heleno","lastName":"Cardoso","suffix":""}],"badges":[],"createdAt":"2024-06-21 16:16:04","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4618214/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4618214/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s11600-024-01512-2","type":"published","date":"2025-01-04T15:57:09+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":73094825,"identity":"1f957a5a-8346-4fd9-9f3e-7784b012c446","added_by":"auto","created_at":"2025-01-06 16:24:31","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1919326,"visible":true,"origin":"","legend":"","description":"","filename":"BombarCardoso2024042920240623.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4618214/v1_covered_6f548eb7-76d1-4c29-b5ab-57533218e674.pdf"}],"financialInterests":"","formattedTitle":"Experimental investigation of the evolution of bed topography in an asymmetrical confluence","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":true,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"acta-geophysica","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"agph","sideBox":"Learn more about [Acta Geophysica](http://link.springer.com/journal/11600)","snPcode":"11600","submissionUrl":"https://www.editorialmanager.com/agph/default2.aspx","title":"Acta Geophysica","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Confluence, Mobile bed, Time evolution, Morpho-dynamics, Sediment transport","lastPublishedDoi":"10.21203/rs.3.rs-4618214/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4618214/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"This study assessed the time evolution of the bed morphology of six experiments performed by Bombar and Cardoso (2020) on mobile bed confluences. 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