{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,13]],"date-time":"2026-03-13T23:32:50Z","timestamp":1773444770259,"version":"3.50.1"},"reference-count":26,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2021,6,22]],"date-time":"2021-06-22T00:00:00Z","timestamp":1624320000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100010661","name":"Horizon 2020 Framework Programme","doi-asserted-by":"publisher","award":["814958"],"award-info":[{"award-number":["814958"]}],"id":[{"id":"10.13039\/100010661","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The present paper assesses the performance and characteristics of fiber Bragg grating sensors, with a special interest in their applications in hydraulic machinery and systems. The hydropower industry is turning to this technology with high expectations of obtaining high quality data to validate and calibrate numerical models that could be used as digital twins of key assets, further strengthening the sector\u2019s relevant position within industry 4.0. Prior to any validation, fiber Bragg grating sensors\u2019 ability to perform well underwater for long periods of time with minimal degradation, and their ease of scalability, drew the authors\u00b4 attention. A simplified modal analysis of a partially submerged beam is proposed here as a first step to validate the potential of this type of technology for hydropower applications. Fiber Bragg grating sensors are used to obtain the beam\u2019s natural frequencies and to damp vibrations under different conditions. The results are compared with more established waterproof electric strain gauges and a laser vibrometer with good agreement. The presence of several sensors in a single fiber ensures high spatial resolution, fundamental to precisely determine vibration patterns, which is a main concern in this industry. In this work, the beam\u2019s vibration patterns have been successfully captured under different excitations and conditions.<\/jats:p>","DOI":"10.3390\/s21134272","type":"journal-article","created":{"date-parts":[[2021,6,22]],"date-time":"2021-06-22T22:10:59Z","timestamp":1624399859000},"page":"4272","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["Fiber Bragg Grating Sensors for Underwater Vibration Measurement: Potential Hydropower Applications"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5814-9460","authenticated-orcid":false,"given":"Oscar","family":"de la Torre","sequence":"first","affiliation":[{"name":"Barcelona Fluids & Energy Lab, Universitat Polit\u00e9cnica de Catalunya, 08028 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ignazio","family":"Floris","sequence":"additional","affiliation":[{"name":"ITEAM, Universitat Politecnica de Valencia, 46022 Valencia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Salvador","family":"Sales","sequence":"additional","affiliation":[{"name":"ITEAM, Universitat Politecnica de Valencia, 46022 Valencia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9374-7749","authenticated-orcid":false,"given":"Xavier","family":"Escaler","sequence":"additional","affiliation":[{"name":"Barcelona Fluids & Energy Lab, Universitat Polit\u00e9cnica de Catalunya, 08028 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,6,22]]},"reference":[{"key":"ref_1","unstructured":"(2021, January 18). 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