Recycling control by divertor pumping in the closed helical divertor of LHD

Recycling control by divertor pumping in the closed helical divertor of LHD | 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 Recycling control by divertor pumping in the closed helical divertor of LHD Gen Motojima, Suguru Masuzaki, Tomohiro Morisaki, Mamoru Shoji, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6971663/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 Controlling hydrogen fuel particles is critical for achieving a steady-state operation in magnetic confinement fusion devices. In the Large Helical Device, efforts to control wall recycling have led to the development of a closed helical divertor (CHD) with integrated in-vessel pumping systems. This paper review presents the conceptual evolution, engineering implementation, and experimental validation of the CHD, highlighting its role in enhancing neutral particle compression and recycling control. By applying both cryo-sorption and non-evaporable getter pumps within the CHD, significant improvements in neutral pressure compression, density control, and impurity exhaust were demonstrated. These developments enable access to control the recycling, improve energy confinement, and operational flexibility during long-pulse discharges. The results provide a solid experimental foundation for integrating advanced divertor pumping strategies into future steady-state fusion reactors. Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Reviewers agreed at journal 02 May, 2026 Reviewers agreed at journal 07 Jan, 2026 Reviewers invited by journal 09 Jul, 2025 Editor assigned by journal 27 Jun, 2025 Submission checks completed at journal 25 Jun, 2025 First submitted to journal 25 Jun, 2025 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-6971663","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":482743482,"identity":"da1c2ad0-3aa9-4d41-86a9-5bb239236d5a","order_by":0,"name":"Gen 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