{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,21]],"date-time":"2026-02-21T05:00:04Z","timestamp":1771650004736,"version":"3.50.1"},"reference-count":33,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2024,6,4]],"date-time":"2024-06-04T00:00:00Z","timestamp":1717459200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Deanship of Scientific Research and Libraries, Princess Nourah bint Abdulrahman University","award":["RPFAP-24-1445"],"award-info":[{"award-number":["RPFAP-24-1445"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>This numerical investigation explores the enhanced control of the 3D natural convection (NC) within a cubic cavity filled with graphene\u2013water nanofluids, utilizing a bottom-center-located tree-shaped obstacle and a horizontal magnetic field (MF). The analysis includes the effects of the Rayleigh number (Ra), the solid volume fraction of graphene (\u03c6), the Hartmann number (Ha), and the fins\u2019 length (W). The results show complex flow patterns and thermal behavior within the cavity, indicating the interactive effects of nanofluid properties, the tree-shaped obstacle, and magnetic field effects. The MHD effects reduce the convection, while the addition of graphene improves the thermal conductivity of the fluid, which enhances the heat transfer observed with increasing Rayleigh numbers. The increase in the fins\u2019 length on the heat transfer efficiency is found to be slightly negative, which is attributed to the complex interplay between the enhanced heat transfer surface area and fluid flow disruption. This study presents an original combination of non-destructive methods (magnetic field) and a destructive method (tree-shaped obstacle) for the control of the fluid flow and heat transfer characteristics in a 3D cavity filled with graphene\u2013water nanofluids. In addition, it provides valuable information for optimizing heat transfer control strategies, with applications in electronic cooling, renewable energy systems, and advanced thermal management solutions. The application of a magnetic field was found to reduce the maximum velocity and total entropy generation by about 82% and 76%, respectively. The addition of graphene nanoparticles was found to reduce the maximum velocity by about 5.5% without the magnetic field and to increase it by 1.12% for Ha = 100. Varying the obstacles\u2019 length from W = 0.2 to W = 0.8 led to a reduction in velocity by about 23.6%.<\/jats:p>","DOI":"10.3390\/sym16060692","type":"journal-article","created":{"date-parts":[[2024,6,4]],"date-time":"2024-06-04T07:39:49Z","timestamp":1717486789000},"page":"692","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Control of Three-Dimensional Natural Convection of Graphene\u2013Water Nanofluids Using Symmetrical Tree-Shaped Obstacle and External Magnetic Field"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3373-2481","authenticated-orcid":false,"given":"Walid","family":"Aich","sequence":"first","affiliation":[{"name":"Department of Mechanical Engineering, College of Engineering, University of Ha\u2019il, Ha\u2019il City 81451, Saudi Arabia"},{"name":"Laboratory of Metrology and Energy systems, Department of Energy Engineering, University of Monastir, Monastir 5000, Tunisia"}]},{"given":"In\u00e8s","family":"Hilali-Jaghdam","sequence":"additional","affiliation":[{"name":"Department of Computer Science, Applied College, Princess Nourah bint Abdulrahman University, P.O. Box 84428, Riyadh 11432, Saudi Arabia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2239-9142","authenticated-orcid":false,"given":"Amnah","family":"Alshahrani","sequence":"additional","affiliation":[{"name":"Department of Computer Science, Applied College, Princess Nourah bint Abdulrahman University, P.O. Box 84428, Riyadh 11432, Saudi Arabia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8916-1246","authenticated-orcid":false,"given":"Chemseddine","family":"Maatki","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, College of Engineering, Imam Mohammad Ibn Saud Islamic University (IMSIU), Riyadh 11432, Saudi Arabia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6819-3695","authenticated-orcid":false,"given":"Badr M.","family":"Alshammari","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering, University of Ha\u2019il, Ha\u2019il City 81451, Saudi Arabia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4368-7458","authenticated-orcid":false,"given":"Lioua","family":"Kolsi","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, College of Engineering, University of Ha\u2019il, Ha\u2019il City 81451, Saudi Arabia"},{"name":"Laboratory of Metrology and Energy systems, Department of Energy Engineering, University of Monastir, Monastir 5000, Tunisia"}]}],"member":"1968","published-online":{"date-parts":[[2024,6,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"132564","DOI":"10.1016\/j.colsurfa.2023.132564","article-title":"Natural convection and entropy generation of Fe3O4-H2O nanofluids in square cavities with cylindrical grooves under magnetic field","volume":"679","author":"Liu","year":"2023","journal-title":"Colloids Surf. 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