{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:47:12Z","timestamp":1760060832309,"version":"build-2065373602"},"reference-count":43,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2025,9,19]],"date-time":"2025-09-19T00:00:00Z","timestamp":1758240000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Transylvania University of Brasov HBS"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>This study presents a morphing Non-Uniform Rational B-Spline (NURBS) optimization method for enhancing sports car aerodynamics, with performance evaluation conducted in the vehicle\u2019s symmetry plane. The morphing approach enables precise, smooth deformations of rear-end and spoiler geometries while preserving shape continuity, allowing controlled aerodynamic modifications suitable for comparative analysis. Flow simulations were carried out in ANSYS Fluent 2022 using the Reynolds-Averaged Navier\u2013Stokes (RANS) equations with the standard k-\u03b5 turbulence model, selected for its stability and accuracy in predicting boundary-layer evolution, wake behavior, and flow separation in external automotive flows. Three configurations were assessed: the baseline model, a spoiler-equipped version, and two NURBS-morphed designs. The symmetry-plane evaluation ensured bilateral balance across all variants, enabling direct comparison of drag and lift performance. The results show that the proposed morphing strategy achieved notable lift reduction and favorable drag-to-lift ratios while maintaining manufacturability. The findings demonstrate that combining NURBS-based morphing with symmetry-plane aerodynamic assessment offers an efficient, reliable framework for vehicle aerodynamic optimization, bridging geometric flexibility with robust computational evaluation.<\/jats:p>","DOI":"10.3390\/sym17091571","type":"journal-article","created":{"date-parts":[[2025,9,19]],"date-time":"2025-09-19T12:33:32Z","timestamp":1758285212000},"page":"1571","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["NURBS Morphing Optimization of Drag and Lift in a Coupe-Class Vehicle Using Symmetry-Plane Comparison of Aerodynamic Performance"],"prefix":"10.3390","volume":"17","author":[{"given":"Sohaib","family":"Guendaoui","sequence":"first","affiliation":[{"name":"Research Laboratory in Science and Engineering, Faculty of Science and Technology, Sidi Mohamed Ben Abdellah University, Fez 30000, Morocco"}]},{"given":"Abdeslam","family":"El Akkad","sequence":"additional","affiliation":[{"name":"Research Laboratory in Science and Engineering, Faculty of Science and Technology, Sidi Mohamed Ben Abdellah University, Fez 30000, Morocco"},{"name":"Department of Mathematics Regional Centre for Professions of Education and Training (CRMEF F\u00e8s-Mekn\u00e8s), Fez 30050, Morocco"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9861-8316","authenticated-orcid":false,"given":"Ahmed","family":"El Khalfi","sequence":"additional","affiliation":[{"name":"Research Laboratory in Science and Engineering, Faculty of Science and Technology, Sidi Mohamed Ben Abdellah University, Fez 30000, Morocco"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8679-2579","authenticated-orcid":false,"given":"Sorin","family":"Vlase","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Faculty of Mechanical Engineering, Transylvania University of Brasov, B-dul Eroilor 29, 500036 Brasov, Romania"},{"name":"Institute for Solid Mechanics of the Romanian Academy, Str.C. Mille. 15, 030137 Bucharest, Romania"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1552-3763","authenticated-orcid":false,"given":"Marin","family":"Marin","sequence":"additional","affiliation":[{"name":"Department of Mathematics and Informatics, Transylvania University of Brasov, B-dul Eroilor 29, 500036 Brasov, Romania"},{"name":"Romanian Academy of the Scientists, 015342 Bucharest, Romania"}]}],"member":"1968","published-online":{"date-parts":[[2025,9,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"(1958). Aerodynamics. Nature, 181, 671\u2013672.","DOI":"10.1038\/181671d0"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1604","DOI":"10.2514\/1.C032491","article-title":"Aerodynamic Design Optimization Studies of a Blended-Wing-Body Aircraft","volume":"51","author":"Lyu","year":"2014","journal-title":"J. Aircr."},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Firoozi, A.A., and Hejazi, F. (2024). 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