Dynamic stall on airfoils with leading-edge tubercles

Dynamic stall on airfoils with leading-edge tubercles | 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 Dynamic stall on airfoils with leading-edge tubercles Pere Valls Badia, Stefan Hickel, Fulvio Scarano, Mogeng Li This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4911604/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 15 Feb, 2025 Read the published version in Experiments in Fluids → Version 1 posted 9 You are reading this latest preprint version Abstract Leading-edge protuberances on airfoils have been shown to soften the onset of aerodynamic stall and to increase lift in the post-stall regime. The present study examines the effect of tubercles during dynamic stall. Pitching airfoils with tubercles of different amplitudes are studied by wind-tunnel experiments, where the three-dimensional time-resolved velocity field is determined using large-scale particle tracking velocimetry (PTV). Computational fluid dynamics (CFD) simulations are carried out that complement the experimental observations providing pressure distribution and aerodynamic forces. The dynamic stall is dominated by a vortex formed at the leading-edge; we characterize the vorticity, circulation , and advection path of this dynamic-stall vortex (DSV). The presence of the tubercles profoundly modifies the boundary layer from the leading-edge. The roll-up of the vorticity sheet is significantly delayed compared to a conventional airfoil, resulting in a weaker DSV. The vortex formation is shifted downstream, with the overall effect of a weaker and shorter lift overshoot, in turn enabling a quicker transition to deep stall. Regions of flow separation (stall cells) are visibly compartmentalized with a stable spacing of two tubercles wavelengths. Pitching airfoil dynamic stall tubercles wind tunnel particle tracking CFD vortex Full Text Additional Declarations No competing interests reported. Supplementary Files figure7.mp4 figure8.mp4 figure9.mp4 figure10.mp4 figure11.mp4 figure12.mp4 figure14.mp4 figure15.mp4 figure16.mp4 figure17.mp4 figure18.mp4 Cite Share Download PDF Status: Published Journal Publication published 15 Feb, 2025 Read the published version in Experiments in Fluids → Version 1 posted Editorial decision: Revision requested 07 Oct, 2024 Reviews received at journal 30 Sep, 2024 Reviews received at journal 28 Aug, 2024 Reviewers agreed at journal 16 Aug, 2024 Reviewers agreed at journal 16 Aug, 2024 Reviewers invited by journal 16 Aug, 2024 Editor assigned by journal 16 Aug, 2024 Submission checks completed at journal 16 Aug, 2024 First submitted to journal 14 Aug, 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. 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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-4911604","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":349544228,"identity":"b60d35f7-bec4-4c1b-b821-b4c0e25c6665","order_by":0,"name":"Pere Valls Badia","email":"","orcid":"","institution":"Delft University of Technology, South Holland","correspondingAuthor":false,"prefix":"","firstName":"Pere","middleName":"Valls","lastName":"Badia","suffix":""},{"id":349544229,"identity":"a966120c-a018-4913-88a2-3b082f9bd428","order_by":1,"name":"Stefan Hickel","email":"","orcid":"","institution":"Delft University of Technology, South 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