Particle-Enhanced Temperature-Sensitive Paint: Development and Validation for High-Speed Aerothermodynamic Testing

Particle-Enhanced Temperature-Sensitive Paint: Development and Validation for High-Speed Aerothermodynamic Testing | 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 Particle-Enhanced Temperature-Sensitive Paint: Development and Validation for High-Speed Aerothermodynamic Testing Jinyoung Kim, Mithat Engin, Masaki Okawa, Tsubasa Ikami, Bok Jik Lee, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8884315/v1 This work is licensed under a CC BY 4.0 License Status: Under Revision Version 1 posted 9 You are reading this latest preprint version Abstract Accurate measurement of surface temperature of high-speed vehicles, such as atmospheric entry capsules and space exploration vehicles, is critical for the design of thermal-protection systems and the development of thermal-load mitigation strategies. Temperature-sensitive paint (TSP) has emerged as a piv-otal non-intrusive method for global heat flux measurement in ground-testing facilities. However, conventional TSP formulations suffer under extreme flow 1 conditions, including self-illumination by nozzle flow, rapid fluctuations in temperature and pressure, and low signal-to-noise ratios. To address these challenges, this study presents a particle-enhanced TSP (PE-TSP) incorporating calcium silicate microparticles to increase luminescence intensity, improve temperature sensitivity, and minimize pressure dependency. Development and characterization tests revealed performance gains over a standard TSP formulation: lumines-cence intensity increased by 21%, temperature sensitivity increased by 11%, and pressure dependency was reduced by twice. For validation, both PE-TSP and the standard TSP were applied in a shock tube test section to assess dynamic response to extreme flow condition. The result showed that, owing to the increased signal-to-noise ratio, PE-TSP reduced the standard deviation by up to 33%. These results confirm the applicability of PE-TSP for high-speed aerothermodynamic diagnostics. Temperature-Sensitive Paint Heat Flux Measurement Hypersonic Flow Full Text Additional Declarations No competing interests reported. Supplementary Files supplementarymaterial.mp4 Cite Share Download PDF Status: Under Revision Version 1 posted Editorial decision: Revision requested 21 Apr, 2026 Reviews received at journal 21 Apr, 2026 Reviewers agreed at journal 17 Mar, 2026 Reviews received at journal 11 Mar, 2026 Reviewers agreed at journal 26 Feb, 2026 Reviewers invited by journal 25 Feb, 2026 Editor assigned by journal 23 Feb, 2026 Submission checks completed at journal 16 Feb, 2026 First submitted to journal 15 Feb, 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. 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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-8884315","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":597403122,"identity":"e7f9829f-e748-42fc-a9a3-2dc9f9e29269","order_by":0,"name":"Jinyoung Kim","email":"","orcid":"","institution":"Seoul National University","correspondingAuthor":false,"prefix":"","firstName":"Jinyoung","middleName":"","lastName":"Kim","suffix":""},{"id":597403123,"identity":"10f8c761-70c3-4a79-a46b-d33023e5d73b","order_by":1,"name":"Mithat Engin","email":"","orcid":"","institution":"Technical University of 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