Spatially developing drag reduction across a finite oscillating wall

Spatially developing drag reduction across a finite oscillating wall | 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 Spatially developing drag reduction across a finite oscillating wall Marco Galli, Nicolò Scaiola, Ferdinand F.J. Schrijer, Fulvio Scarano This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9303853/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 7 You are reading this latest preprint version Abstract The spatial evolution of a turbulent boundary layer at í µí± í µí±’ τ = 430 developing across a finite spanwise oscillating wall is investigated with normalised oscillation period of í µí±‡ + ≈ 101 and amplitude í µí°´+µí°´+ ≈ 7 corresponding to a skin friction reduction of 32%. The spatial distribution of skin friction is estimated adopting a recently introduced near wall data nonlinear regression method based on the arctangent function, which circumvents the requirement of high wall normal resolution to capture the linear sub-layer. The method viability is assessed with reference data, and the trends of measurement errors are well reproduced in the analysis of the current data. The local impact of the control action is examined by evaluating the spatial development of scalar fields of turbulence statistics as well as conditional quadrant analysis to link the onset and recovery transients to turbulence events. The boundary layer response is observed to follow an exponential decay law for the skin friction spatial evolution. The decay length-scale corresponds to 0.7 boundary layer thicknesses δ for the onset transient and 1δ for the recovery one. Second-order statistics display shorter transients, owed to the dependence on short-scales compared to the integral nature of skin friction. Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Reviews received at journal 14 May, 2026 Reviewers agreed at journal 17 Apr, 2026 Reviewers agreed at journal 15 Apr, 2026 Reviewers invited by journal 12 Apr, 2026 Editor assigned by journal 07 Apr, 2026 Submission checks completed at journal 06 Apr, 2026 First submitted to journal 02 Apr, 2026 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-9303853","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":619165655,"identity":"76741292-b6ce-4e77-8c31-0da244a3a029","order_by":0,"name":"Marco Galli","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA00lEQVRIie3OMQuCQBTA8RfC3fK09YlQnyAwgjAI+iqCXyBocQhz0sWP4IcxBFta2hyNViHHpujOtgbPseH+2z3ud/cAdLp/rdkTMB4DIHhTcZ4USuK7BBaWkpCdicEYAjCjYCRZxPzW+a4HzH5W1IZEOzCLQbIu8EByMeYEzM6vRAiWryK+JKdEEMdMKEJAV0WCV/+LXQrylr8oCa++i5EhSDyGlMi8nmCw2uSVIKWKXNJH3YURzNPzvW6PW+JptmyGCBjo/k4G78v48JM6nU6ngw/RzTtH/kN9mQAAAABJRU5ErkJggg==","orcid":"","institution":"Delft University of Technology","correspondingAuthor":true,"prefix":"","firstName":"Marco","middleName":"","lastName":"Galli","suffix":""},{"id":619165657,"identity":"c3c51757-dc70-4c1f-8c72-1912c8f1f99a","order_by":1,"name":"Nicolò Scaiola","email":"","orcid":"","institution":"Politecnico di Torino","correspondingAuthor":false,"prefix":"","firstName":"Nicolò","middleName":"","lastName":"Scaiola","suffix":""},{"id":619165659,"identity":"3972b173-999c-4723-b461-525750cce079","order_by":2,"name":"Ferdinand F.J. 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