Three-Dimensional Flame-Head Bifurcation and Compression– Hydrodynamic Coupling in LES of Premixed Hydrogen-Air Propagation in a Half-Open Channel

Three-Dimensional Flame-Head Bifurcation and Compression– Hydrodynamic Coupling in LES of Premixed Hydrogen-Air Propagation in a Half-Open Channel | 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 Three-Dimensional Flame-Head Bifurcation and Compression– Hydrodynamic Coupling in LES of Premixed Hydrogen-Air Propagation in a Half-Open Channel Youquan Yuan, Jiandong He This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9517192/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 6 You are reading this latest preprint version Abstract Large-eddy simulations were used to examine premixed hydrogen-air flame propagation in a three-dimensional half-open channel. The stoichiometric mixture was taken as the reference condition, and neighboring lean and rich mixtures were introduced to test whether changes in equivalence ratio alter the pathway itself or mainly shift its onset and late-stage strength. In all three cases, wall confinement quickly suppresses the initial quasi-spherical kernel expansion and reorganizes the flame into a spanwise-stratified front, with the clearest head bifurcation on the center plane. Within a common LES closure, four coupled precursor quantities are tracked: flame-head bifurcation, ahead-of-flame compression, tip-center velocity separation, and wake backflow. The rich case enters the coupled precursor regime earliest in absolute time, whereas the stoichiometric case reaches the strongest late-stage structural-compressive state at matched normalized stages. These results support a single confinement-organized precursor pathway in which equivalence ratio mainly shifts entry timing and late-stage amplification rather than introducing a different mechanism. A late-stage collapse of the adaptive time step is observed near termination, but it is treated here as a secondary interpretive issue rather than as a primary mechanism claim. hydrogen-air flame large-eddy simulation half-open channel flame-head bifurcation ahead-of-flame compression precursor pathway Full Text Additional Declarations No competing interests reported. Supplementary Files FigS06terminaldotplot.tiff FigS05hydrodynamiccomparison.tiff ESM2onlineresource2meshrobustness.pdf FigS08aheadwindowrobustness.tiff FigS07frontdefinitionrobustness.tiff ESM1onlineresource1.pdf FigS10normalizedDb.tiff FTaCsourcedataandscriptsv01.zip FigS09wakewindowrobustness.tiff FigS11normalizeddp.tiff FigS03temperaturephi1p1.tiff FigS04velocityphi1p1.tiff FigS01temperaturephi0p9.tiff FigS02velocityphi0p9.tiff TableS03normalizedstagevalues.csv TableS04representativetimerobustnesssupport.csv TableS02thresholdsensitivity.csv TableS01eventonsetrobustness.csv FigS13.tif FigS12.tif FigS14.tif FigS15.tif TableS5.csv Cite Share Download PDF Status: Under Review Version 1 posted Reviews received at journal 15 May, 2026 Reviewers agreed at journal 29 Apr, 2026 Reviewers invited by journal 29 Apr, 2026 Editor assigned by journal 28 Apr, 2026 Submission checks completed at journal 28 Apr, 2026 First submitted to journal 24 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. 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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-9517192","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":633925723,"identity":"64712963-aadd-4e5f-8dff-91ce624a0211","order_by":0,"name":"Youquan Yuan","email":"","orcid":"","institution":"内蒙古工业大学","correspondingAuthor":false,"prefix":"","firstName":"Youquan","middleName":"","lastName":"Yuan","suffix":""},{"id":633925724,"identity":"28de07c2-ffda-4b88-aa38-1750cd5974f6","order_by":1,"name":"Jiandong 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