{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,12]],"date-time":"2026-07-12T03:31:00Z","timestamp":1783827060065,"version":"3.55.0"},"reference-count":41,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2021,8,27]],"date-time":"2021-08-27T00:00:00Z","timestamp":1630022400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100010198","name":"Ministerio de Econom\u00eda, Industria y Competitividad, Gobierno de Espa\u00f1a","doi-asserted-by":"publisher","award":["FIS2016-77849-R"],"award-info":[{"award-number":["FIS2016-77849-R"]}],"id":[{"id":"10.13039\/501100010198","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100019945","name":"Direcci\u00f3 General de Recerca, Generalitat de Catalunya","doi-asserted-by":"publisher","award":["2017-SGR-00785"],"award-info":[{"award-number":["2017-SGR-00785"]}],"id":[{"id":"10.13039\/501100019945","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100006433","name":"Barcelona Supercomputing Center","doi-asserted-by":"publisher","award":["FI-2018-3-0036; FI-2019-1-0017"],"award-info":[{"award-number":["FI-2018-3-0036; FI-2019-1-0017"]}],"id":[{"id":"10.13039\/501100006433","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Fluidic oscillators are often used to modify the forces fluid generates on any given bluff body; they can also be used as flow, pressure or acoustic sensors, with each application requiring a particular oscillator configuration. Regarding the fluidic oscillators\u2019 main performance, a problem which is not yet clarified is the understanding of the feedback channel effect on the oscillator outlet mass flow frequency and amplitude, especially under compressible flow conditions. In order to bring light to this point, a set of three-dimensional Direct Numerical Simulations under compressible flow conditions are introduced in the present paper; four different feedback channel lengths and two inlet Reynolds numbers Re = 12,410 and Re = 18,617 are considered. From the results obtained, it is observed that as the inlet velocity increases, the fluidic oscillator outlet mass flow frequency and amplitude increase. An increase of the feedback channel length decreases the outlet mass flow oscillating frequency. At large feedback channel lengths, the former main oscillation tends to disappear, the jet inside the mixing chamber simply fluctuates at high frequencies. Once the Feedback Channel (FC) length exceeds a certain threshold, the oscillation stops. Under all conditions studied, pressure waves are observed to be traveling along the feedback channels, their origin and interaction with the jet entering the mixing chamber are thoroughly evaluated. The paper proves that jet oscillations are pressure-driven.<\/jats:p>","DOI":"10.3390\/s21175768","type":"journal-article","created":{"date-parts":[[2021,8,31]],"date-time":"2021-08-31T22:58:15Z","timestamp":1630450695000},"page":"5768","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":29,"title":["Fluidic Oscillators, Feedback Channel Effect under Compressible Flow Conditions"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1787-7960","authenticated-orcid":false,"given":"Josep M.","family":"Bergad\u00e0","sequence":"first","affiliation":[{"name":"Fluid Mechanics Department, Universitat Polit\u00e8cnica de Catalunya, 08034 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Masoud","family":"Baghaei","sequence":"additional","affiliation":[{"name":"Fluid Mechanics Department, Universitat Polit\u00e8cnica de Catalunya, 08034 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bhanu","family":"Prakash","sequence":"additional","affiliation":[{"name":"Applus IDIADA Group, Santa Oliva, L\u2019Albornar, 43710 Tarragona, Spain"},{"name":"Department of Physics, Aerospace Engineering Division, Universitat Polit\u00e8cnica de Catalunya, 08034 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0497-9052","authenticated-orcid":false,"given":"Fernando","family":"Mellibovsky","sequence":"additional","affiliation":[{"name":"Department of Physics, Aerospace Engineering Division, Universitat Polit\u00e8cnica de Catalunya, 08034 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,8,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"216","DOI":"10.1017\/jfm.2018.739","article-title":"Properties of a sweeping jet emitted from a fluidic oscillator","volume":"857","author":"Ostermann","year":"2018","journal-title":"J. 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