Design and validation of Self-Aligned Focusing Schlieren optical systems

Design and validation of Self-Aligned Focusing Schlieren optical systems | 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 Design and validation of Self-Aligned Focusing Schlieren optical systems Enrico Zammit, Guido Lapini, Alessandro D'Aguanno, Sergio Lavagnoli This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9473921/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract This work presents recent advancements in the Self-Aligned Focusing Schlieren (SAFS) technique for quantitative flow visualization and introduces HORUS, a predictive modeling tool developed to support the design and optimization of SAFS systems. The study pursued three main objectives: (i) to develop practical expertise for the effective implementation of SAFS in compressible-flow facilities, (ii) to establish and validate HORUS for predicting key optical parameters and system performance, and (iii) to experimentally assess SAFS capabilities in representative flow environments. Two experimental campaigns were conducted at the von Karman Institute for Fluid Dynamics. The first involved a supersonic ogive configuration and demonstrated close quantitative agreement between HORUS predictions and measured optical performance. The second was performed on a linear transonic turbine cascade and confirmed the model’s accuracy in predicting field of view, depth of field, vignetting effects, and cutoff-level behavior. The experiments also validated a revised cutoff formulation for opposite-side Rochon prism–Ronchi ruling configurations. Overall, the strong correlation between model and experiment establishes HORUS as a reliable predictive framework for SAFS design, facilitating the application of the technique to complex compressible-flow investigations. Aeronautics and Astronautics Plasma and Fluids SAFS Schlieren Compressible flows Turbomachinery Full Text Additional Declarations The authors declare no competing interests. Cite Share Download PDF Status: Posted Version 1 posted 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-9473921","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":626432087,"identity":"7430a1cb-cbf2-4485-b2bc-a9f128cbac88","order_by":0,"name":"Enrico 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