Improving Buildings Thermal Comfort by Modifying HVAC Systems Terminal Units

Improving Buildings Thermal Comfort by Modifying HVAC Systems Terminal Units | 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 Improving Buildings Thermal Comfort by Modifying HVAC Systems Terminal Units Hacene Kadi, Abderazak Bennia, Ahmed Benabed, Fatma Zohra Hadagha, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8544613/v1 This work is licensed under a CC BY 4.0 License Status: Under Revision Version 1 posted 8 You are reading this latest preprint version Abstract This work presents numerical study using the computational fluid dynamics (CFD) simulations, employing the commercial ANSYS Fluent software. Aiming to improve the occupants’ thermal comfort in building environment by modifying heating, ventilation and air conditioning (HVAC) systems terminal units. Evaluating and comparing the airflow characteristics and occupant’s thermal comfort inside an office room, occupied by multi-cone ceiling air diffuser, which will be referred to CD. Then using the same air diffuser occupied with inclined undulated fins called inserted lobes, this diffuser is referred to LD. The thermal comfort was assessed in terms of percentage of dissatisfaction (PD) and draft rate (DR) indices. The optimal mesh density was selected after testing four different mesh densities. This numerical study was validated using SST k-w turbulent model. The results showed a reduction in air velocity and noticeable improvement in thermal comfort after inserting the inserted lobes by 20% and 5% in terms of PD and DR. Numerical simulation computational fluid dynamics (CFD) thermal comfort buildings ceiling air diffuser inclined inserted lobes Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Revision Version 1 posted Editorial decision: Revision requested 02 Mar, 2026 Reviewers agreed at journal 24 Jan, 2026 Reviews received at journal 22 Jan, 2026 Reviewers agreed at journal 17 Jan, 2026 Reviewers invited by journal 15 Jan, 2026 Editor assigned by journal 10 Jan, 2026 Submission checks completed at journal 09 Jan, 2026 First submitted to journal 07 Jan, 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. 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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-8544613","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":576317728,"identity":"dc7defed-30b2-4c82-987f-c6cdf88c9a23","order_by":0,"name":"Hacene 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Aiming to improve the occupants\u0026rsquo; thermal comfort in building environment by modifying heating, ventilation and air conditioning (HVAC) systems terminal units. Evaluating and comparing the airflow characteristics and occupant\u0026rsquo;s thermal comfort inside an office room, occupied by multi-cone ceiling air diffuser, which will be referred to CD. Then using the same air diffuser occupied with inclined undulated fins called inserted lobes, this diffuser is referred to LD. The thermal comfort was assessed in terms of percentage of dissatisfaction (PD) and draft rate (DR) indices. The optimal mesh density was selected after testing four different mesh densities. This numerical study was validated using SST \u003cem\u003ek-w\u003c/em\u003e turbulent model. 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