{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,6]],"date-time":"2026-02-06T03:17:21Z","timestamp":1770347841924,"version":"3.49.0"},"reference-count":26,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2025,7,31]],"date-time":"2025-07-31T00:00:00Z","timestamp":1753920000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Aerospace"],"abstract":"<jats:p>The advancement of computational capabilities has allowed for more efficient airfoil analysis and design. Consequently, it has become possible to expand the design space and explore new geometries and configurations. However, the current state of development does not yet support a fully automated optimization process. Instead, the newly introduced capabilities have effectively transferred the previously trial-and-error-based approach used in geometry design to the formulation of the optimization problem. The goal of this work is to study the formulation of an optimization problem and propose a new methodology that better portrays the aircraft\u2019s requirements for airfoil performance. The new objective function, added to an existing tool, estimates the main performance parameters of an aircraft for the Air Cargo Challenge (ACC) 2022 competition using a method that extrapolates the characteristics of the airfoil into the aircraft\u2019s performance. In addition, the traditional relative aerodynamic property improvements, in this work, are coupled with the performance results to smooth the polar curve of the resulting airfoil. The optimization algorithm is based on the free-gradient technique Particle Swarm Optimization (PSO), using the B-spline parametrization and a coupled viscous\/inviscid interaction method as the flow solver.<\/jats:p>","DOI":"10.3390\/aerospace12080685","type":"journal-article","created":{"date-parts":[[2025,8,5]],"date-time":"2025-08-05T10:50:21Z","timestamp":1754391021000},"page":"685","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Low-Speed Airfoil Optimization for Improved Off-Design Performance"],"prefix":"10.3390","volume":"12","author":[{"given":"Guilherme F. S.","family":"Pangas","sequence":"first","affiliation":[{"name":"Centre for Mechanical and Aerospace Science and Technologies (C-MAST), Universidade da Beira Interior, 6201-001 Covilh\u00e3, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7814-8679","authenticated-orcid":false,"given":"Pedro V.","family":"Gamboa","sequence":"additional","affiliation":[{"name":"Centre for Mechanical and Aerospace Science and Technologies (C-MAST), Universidade da Beira Interior, 6201-001 Covilh\u00e3, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,7,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Akram, M.T., and Kim, M.-H. (2021). CFD Analysis and Shape Optimization of Airfoils Using Class Shape Transformation and Genetic Algorithm\u2014Part I. Appl. Sci., 11.","DOI":"10.3390\/app11093791"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Belda, M., and Hyhl\u00edk, T. (2024). 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Available online: http:\/\/hdl.handle.net\/10400.6\/11940."}],"container-title":["Aerospace"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2226-4310\/12\/8\/685\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,9]],"date-time":"2025-10-09T18:19:50Z","timestamp":1760033990000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2226-4310\/12\/8\/685"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,7,31]]},"references-count":26,"journal-issue":{"issue":"8","published-online":{"date-parts":[[2025,8]]}},"alternative-id":["aerospace12080685"],"URL":"https:\/\/doi.org\/10.3390\/aerospace12080685","relation":{},"ISSN":["2226-4310"],"issn-type":[{"value":"2226-4310","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,7,31]]}}}