{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,15]],"date-time":"2026-10-15T01:39:42Z","timestamp":1792028382852,"version":"4.4.0"},"reference-count":60,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2023,11,22]],"date-time":"2023-11-22T00:00:00Z","timestamp":1700611200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001659","name":"German Research Foundation (DFG)","doi-asserted-by":"publisher","award":["446965891"],"award-info":[{"award-number":["446965891"]}],"id":[{"id":"10.13039\/501100001659","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Bioengineering"],"abstract":"<jats:p>In the human phonation process, acoustic standing waves in the vocal tract can influence the fluid flow through the glottis as well as vocal fold oscillation. To investigate the amount of acoustic back-coupling, the supraglottal flow field has been recorded via high-speed particle image velocimetry (PIV) in a synthetic larynx model for several configurations with different vocal tract lengths. Based on the obtained velocity fields, acoustic source terms were computed. Additionally, the sound radiation into the far field was recorded via microphone measurements and the vocal fold oscillation via high-speed camera recordings. The PIV measurements revealed that near a vocal tract resonance frequency fR, the vocal fold oscillation frequency fo (and therefore also the flow field\u2019s fundamental frequency) jumps onto fR. This is accompanied by a substantial relative increase in aeroacoustic sound generation efficiency. Furthermore, the measurements show that fo-fR-coupling increases vocal efficiency, signal-to-noise ratio, harmonics-to-noise ratio and cepstral peak prominence. At the same time, the glottal volume flow needed for stable vocal fold oscillation decreases strongly. All of this results in an improved voice quality and phonation efficiency so that a person phonating with fo-fR-coupling can phonate longer and with better voice quality.<\/jats:p>","DOI":"10.3390\/bioengineering10121343","type":"journal-article","created":{"date-parts":[[2023,11,22]],"date-time":"2023-11-22T08:47:43Z","timestamp":1700642863000},"page":"1343","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["An Investigation of Acoustic Back-Coupling in Human Phonation on a Synthetic Larynx Model"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0009-0001-8731-2765","authenticated-orcid":false,"given":"Christoph","family":"N\u00e4ger","sequence":"first","affiliation":[{"name":"Institute of Fluid Mechanics, Friedrich-Alexander-Universit\u00e4t Erlangen-N\u00fcrnberg, Cauerstra\u00dfe 4, 91058 Erlangen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4902-0534","authenticated-orcid":false,"given":"Stefan","family":"Kniesburges","sequence":"additional","affiliation":[{"name":"Division of Phoniatrics and Pediatric Audiology, Department of Otorhinolaryngology, Head & Neck Surgery, University Hospital Erlangen, Medical School, Friedrich-Alexander-Universit\u00e4t Erlangen-N\u00fcrnberg, Waldstrasse 1, 91054 Erlangen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bogac","family":"Tur","sequence":"additional","affiliation":[{"name":"Division of Phoniatrics and Pediatric Audiology, Department of Otorhinolaryngology, Head & Neck Surgery, University Hospital Erlangen, Medical School, Friedrich-Alexander-Universit\u00e4t Erlangen-N\u00fcrnberg, Waldstrasse 1, 91054 Erlangen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2148-6703","authenticated-orcid":false,"given":"Stefan","family":"Schoder","sequence":"additional","affiliation":[{"name":"Aeroacoustics and Vibroacoustics Group, Institute of Fundamentals and Theory in Electrical Engineering, Graz University of Technology, Inffeldgasse 16, 8010 Graz, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2389-1681","authenticated-orcid":false,"given":"Stefan","family":"Becker","sequence":"additional","affiliation":[{"name":"Institute of Fluid Mechanics, Friedrich-Alexander-Universit\u00e4t Erlangen-N\u00fcrnberg, Cauerstra\u00dfe 4, 91058 Erlangen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,11,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"437","DOI":"10.1146\/annurev-fluid-011212-140636","article-title":"Fluid Dynamics of Human Phonation and Speech","volume":"45","author":"Mittal","year":"2013","journal-title":"Annu. 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