{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:38:50Z","timestamp":1760060330956,"version":"build-2065373602"},"reference-count":36,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2025,8,22]],"date-time":"2025-08-22T00:00:00Z","timestamp":1755820800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Computation"],"abstract":"<jats:p>This study presents a semi-empirical approach to generalizing the acoustic radiation generated by serrated airfoil configurations, based on small-scale aerodynamic\/acoustic experiments and functional regression techniques. In the context of passive noise reduction strategies, such as leading-edge and trailing-edge serrations, acoustic measurements are performed in a controlled subsonic wind tunnel environment. Sound pressure level (SPL) spectra and acoustic power metrics are acquired for various geometric configurations and flow conditions. These spectral data are then analyzed using regression-based modeling techniques\u2014linear, quadratic, logarithmic, and exponential forms\u2014to capture the dependence of acoustic emission on key geometric and flow-related variables (e.g., serration amplitude, wavelength, angle of attack), without relying explicitly on predefined nondimensional numbers. The resulting predictive models aim to describe SPL behavior across relevant frequency bands (e.g., broadband or 1\/3 octave) and to extrapolate acoustic trends for configurations beyond those tested. The proposed methodology allows for the identification of compact functional relationships between configuration parameters and acoustic output, offering a practical tool for the preliminary design and optimization of low-noise serrated profiles. The findings are intended to support both physical understanding and engineering application, bridging experimental data and parametric acoustic modeling in aerodynamic noise control.<\/jats:p>","DOI":"10.3390\/computation13090203","type":"journal-article","created":{"date-parts":[[2025,8,22]],"date-time":"2025-08-22T11:50:31Z","timestamp":1755863431000},"page":"203","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["SPL-Based Modeling of Serrated Airfoil Noise via Functional Regression and Ensemble Learning"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0460-7558","authenticated-orcid":false,"given":"Andrei-George","family":"Totu","sequence":"first","affiliation":[{"name":"National Research and Development Institute for Gas Turbines COMOTI, 220D Iuliu Maniu, 061126 Bucharest, Romania"},{"name":"Faculty of Aerospace Engineering, National University of Science and Technology Politehnica Bucharest, 1-7 Polizu Street, 1, 011061 Bucharest, Romania"}]},{"given":"Daniel-Eugeniu","family":"Crun\u021beanu","sequence":"additional","affiliation":[{"name":"Faculty of Aerospace Engineering, National University of Science and Technology Politehnica Bucharest, 1-7 Polizu Street, 1, 011061 Bucharest, Romania"}]},{"given":"Lumini\u021ba","family":"Dr\u0103g\u0103\u0219anu","sequence":"additional","affiliation":[{"name":"National Research and Development Institute for Gas Turbines COMOTI, 220D Iuliu Maniu, 061126 Bucharest, Romania"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0669-8131","authenticated-orcid":false,"given":"Grigore","family":"Cican","sequence":"additional","affiliation":[{"name":"National Research and Development Institute for Gas Turbines COMOTI, 220D Iuliu Maniu, 061126 Bucharest, Romania"},{"name":"Faculty of Aerospace Engineering, National University of Science and Technology Politehnica Bucharest, 1-7 Polizu Street, 1, 011061 Bucharest, Romania"}]},{"given":"Constantin","family":"Leven\u021biu","sequence":"additional","affiliation":[{"name":"Faculty of Aerospace Engineering, National University of Science and Technology Politehnica Bucharest, 1-7 Polizu Street, 1, 011061 Bucharest, Romania"}]}],"member":"1968","published-online":{"date-parts":[[2025,8,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Ryi, J., and Choi, J. 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