{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,16]],"date-time":"2026-04-16T16:28:47Z","timestamp":1776356927599,"version":"3.51.2"},"reference-count":39,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2019,5,15]],"date-time":"2019-05-15T00:00:00Z","timestamp":1557878400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003086","name":"Eusko Jaurlaritza","doi-asserted-by":"publisher","award":["TEC2015-638263-C03-1-R"],"award-info":[{"award-number":["TEC2015-638263-C03-1-R"]}],"id":[{"id":"10.13039\/501100003086","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003086","name":"Eusko Jaurlaritza","doi-asserted-by":"publisher","award":["IT933-16"],"award-info":[{"award-number":["IT933-16"]}],"id":[{"id":"10.13039\/501100003086","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003086","name":"Eusko Jaurlaritza","doi-asserted-by":"publisher","award":["KK-2017\/00033"],"award-info":[{"award-number":["KK-2017\/00033"]}],"id":[{"id":"10.13039\/501100003086","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003086","name":"Eusko Jaurlaritza","doi-asserted-by":"publisher","award":["KK-2017\/00089"],"award-info":[{"award-number":["KK-2017\/00089"]}],"id":[{"id":"10.13039\/501100003086","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003086","name":"Eusko Jaurlaritza","doi-asserted-by":"publisher","award":["KK-2018\/00078"],"award-info":[{"award-number":["KK-2018\/00078"]}],"id":[{"id":"10.13039\/501100003086","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Among the different available optical technologies, fibre bundle-based reflective optical sensors represent an interesting alternative for parameter monitorization in aero engines. Tip clearance is one of the parameters of great concern for engine designers and engineers. In the framework of this optical technology, three fibre-based reflective optical sensors have been compared. Two of them are custom designed and based on the same geometrical fibre arrangement, whereas the third one is commercially available and relies on a different geometrical arrangement of the fibres. Their performance has been compared in clearance measurements carried out during an experimental program followed at a transonic wind tunnel for aero turbines. The custom-designed solution that operates in the most sensitive part of its response curve proved to be by far the most reliable tool for clearance measurements. Its high resolution opens up the possibility to detect small blade features such as cracks, reflectivity changes, etc. that otherwise could not be tracked. These results show that the detection of unexpected features on blade tips may have an important effect on how the clearance is calculated, ultimately giving rise to corrective actions.<\/jats:p>","DOI":"10.3390\/s19102244","type":"journal-article","created":{"date-parts":[[2019,5,15]],"date-time":"2019-05-15T11:37:40Z","timestamp":1557920260000},"page":"2244","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Performance Comparison of Three Fibre-Based Reflective Optical Sensors for Aero Engine Monitorization"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8681-2776","authenticated-orcid":false,"given":"Rub\u00e9n","family":"Fern\u00e1ndez-Bello","sequence":"first","affiliation":[{"name":"Communications Engineering Department, University of the Basque Country UPV\/EHU, Ingeniero Torres Quevedo Plaza 1, E-48013 Bilbao, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0349-3037","authenticated-orcid":false,"given":"Josu","family":"Amorebieta","sequence":"additional","affiliation":[{"name":"Communications Engineering Department, University of the Basque Country UPV\/EHU, Ingeniero Torres Quevedo Plaza 1, E-48013 Bilbao, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Josu","family":"Beloki","sequence":"additional","affiliation":[{"name":"Fundaci\u00f3n Centro de Tecnolog\u00edas Aeron\u00e1uticas (CTA), Bizkaia Technological Park, E-48170 Zamudio, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6217-6229","authenticated-orcid":false,"given":"Gotzon","family":"Aldabaldetreku","sequence":"additional","affiliation":[{"name":"Communications Engineering Department, University of the Basque Country UPV\/EHU, Ingeniero Torres Quevedo Plaza 1, E-48013 Bilbao, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Iker","family":"Garc\u00eda","sequence":"additional","affiliation":[{"name":"AOTECH, Advanced Optical Technologies S.L., E-48002 Bilbao, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9137-1733","authenticated-orcid":false,"given":"Joseba","family":"Zubia","sequence":"additional","affiliation":[{"name":"Communications Engineering Department, University of the Basque Country UPV\/EHU, Ingeniero Torres Quevedo Plaza 1, E-48013 Bilbao, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1107-2400","authenticated-orcid":false,"given":"Gaizka","family":"Durana","sequence":"additional","affiliation":[{"name":"Communications Engineering Department, University of the Basque Country UPV\/EHU, Ingeniero Torres Quevedo Plaza 1, E-48013 Bilbao, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,5,15]]},"reference":[{"key":"ref_1","unstructured":"Holeski, D.E., and Futral, S.M. 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