{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,5]],"date-time":"2026-08-05T07:23:24Z","timestamp":1785914604471,"version":"3.56.0"},"reference-count":31,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2025,9,16]],"date-time":"2025-09-16T00:00:00Z","timestamp":1757980800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"The Universidad Distrital Francisco Jos\u00e9 de Caldas","award":["PIICI-2024-2032"],"award-info":[{"award-number":["PIICI-2024-2032"]}]}],"content-domain":{"domain":["www.mdpi.com"],"crossmark-restriction":true},"short-container-title":["Biomimetics"],"abstract":"<jats:p>The peregrine falcon, known as the fastest bird in the world, has been studied for its ability to stabilize during high-speed dives, a capability attributed to the configuration of its dorsal feathers. These feathers have inspired the design of vortex generators devices that promote controlled turbulence to delay boundary layer separation on aircraft wings and turbine blades. This study presents an experimental wind tunnel investigation of a bio-inspired peregrine falcon prototype, equipped with movable artificial feathers, a hot-wire anemometer, and a 3D accelerometer. Wake velocity profiles measured behind the prototype revealed fluctuations associated with feather motion. Spectral analysis of the velocity signals, recorded with oscillating feathers at a wind tunnel speed of 10 m\/s, showed attenuation of specific frequency components, suggesting that feather dynamics may help mitigate wake fluctuations induced by structural vibrations. Three-dimensional acceleration measurements indicated that prototype vibrations remained below 1 g, with peak differences along the X and Z axes ranging from \u22120.06 g to 0.06 g, demonstrating the sensitivity of the vibration sensing system. Root Mean Square (RMS) values of velocity signals increased with wind tunnel speed but decreased as the feather inclination angle rose. When the mean value was subtracted from the signal, higher RMS variability was observed, reflecting increased flow disturbance from feather movement. Fast Fourier Transform (FFT) analysis revealed that, for fixed feather angles, spectral magnitudes increased uniformly with wind speed. In contrast, dynamic feather oscillation produced distinctive frequency peaks, highlighting the feather\u2019s influence on the wake structure in the frequency domain. To complement the experimental findings, 3D CFD simulations were conducted on two HAWT-type wind turbines\u2014one with bio-inspired vortex generators and one without. The simulations showed a significant reduction in turbulent kinetic energy contours in the wake of the modified turbine, particularly in the Y-Z plane, compared to the baseline configuration.<\/jats:p>","DOI":"10.3390\/biomimetics10090622","type":"journal-article","created":{"date-parts":[[2025,9,16]],"date-time":"2025-09-16T07:33:02Z","timestamp":1758007982000},"page":"622","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Experimental and Spectral Analysis of the Wake Velocity Effect in a 3D Falcon Prototype with Oscillating Feathers and Its Application in HAWT with Biomimetic Vortex Generators Using CFD"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6184-8000","authenticated-orcid":false,"given":"Hector","family":"Parra","sequence":"first","affiliation":[{"name":"Engineering Faculty Cajic\u00e1, Universidad Militar Nueva Granada, Bogot\u00e1 111321, Colombia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5480-8588","authenticated-orcid":false,"given":"Javier","family":"Guacaneme","sequence":"additional","affiliation":[{"name":"Facultad de Ingenier\u00eda, Universidad Distrital Francisco Jos\u00e9 de Caldas, Bogot\u00e1 110231, Colombia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5431-8776","authenticated-orcid":false,"given":"Elvis","family":"Gaona","sequence":"additional","affiliation":[{"name":"Facultad de Ingenier\u00eda, Universidad Distrital Francisco Jos\u00e9 de Caldas, Bogot\u00e1 110231, Colombia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3594-4752","authenticated-orcid":false,"given":"Hern\u00e1n Dario","family":"Cer\u00f3n-Mu\u00f1oz","sequence":"additional","affiliation":[{"name":"Escola de Engenharia de S\u00e3o Carlos, Universidade de S\u00e3o Paulo, S\u00e3o Carlos 13566-590, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,9,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"633","DOI":"10.1016\/j.egypro.2019.02.215","article-title":"Wind turbine noise and its mitigation techniques: A review","volume":"160","author":"Deshmukh","year":"2019","journal-title":"Energy Procedia"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"314","DOI":"10.1016\/j.jsv.2019.02.004","article-title":"Numerical investigation of noise reduction mechanisms in a bio-inspired airfoil","volume":"453","author":"Bodling","year":"2019","journal-title":"J. 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