{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,16]],"date-time":"2026-02-16T19:34:37Z","timestamp":1771270477015,"version":"3.50.1"},"reference-count":34,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2019,11,4]],"date-time":"2019-11-04T00:00:00Z","timestamp":1572825600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000266","name":"Engineering and Physical Sciences Research Council","doi-asserted-by":"publisher","award":["EP\/N025393\/1"],"award-info":[{"award-number":["EP\/N025393\/1"]}],"id":[{"id":"10.13039\/501100000266","id-type":"DOI","asserted-by":"publisher"}]},{"name":"EU SACUT Project through the Marie Curie Industry-Academia Pathways &amp; Partnership (IAPP) action","award":["612118"],"award-info":[{"award-number":["612118"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Accurate average flow velocity determination is essential for flow measurement in many industries, including automotive, chemical, and oil and gas. The ultrasonic transit-time method is common for average flow velocity measurement, but current limitations restrict measurement accuracy, including fluid dynamic effects from unavoidable phenomena such as turbulence, swirls or vortices, and systematic flow meter errors in calibration or configuration. A new spatial averaging method is proposed, based on flexural ultrasonic array transducer technology, to improve measurement accuracy and reduce the uncertainty of the measurement results. A novel two-dimensional flexural ultrasonic array transducer is developed to validate this measurement method, comprising eight individual elements, each forming distinct paths to a single ultrasonic transducer. These paths are distributed in two chordal planes, symmetric and adjacent to a diametral plane. It is demonstrated that the root-mean-square deviation of the average flow velocity, computed using the spatial averaging method with the array transducer is 2.94%, which is lower compared to that of the individual paths ranging from 3.65% to 8.87% with an average of 6.90%. This is advantageous for improving the accuracy and reducing the uncertainty of classical single-path ultrasonic flow meters, and also for conventional multi-path ultrasonic flow meters through the measurement via each flow plane with reduced uncertainty. This research will drive new developments in ultrasonic flow measurement in a wide range of industrial applications.<\/jats:p>","DOI":"10.3390\/s19214786","type":"journal-article","created":{"date-parts":[[2019,11,4]],"date-time":"2019-11-04T04:13:08Z","timestamp":1572840788000},"page":"4786","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Flow Velocity Measurement Using a Spatial Averaging Method with Two-Dimensional Flexural Ultrasonic Array Technology"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2485-8039","authenticated-orcid":false,"given":"Lei","family":"Kang","sequence":"first","affiliation":[{"name":"Department of Physics, University of Warwick, Coventry CV4 7AL, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7170-1830","authenticated-orcid":false,"given":"Andrew","family":"Feeney","sequence":"additional","affiliation":[{"name":"Department of Physics, University of Warwick, Coventry CV4 7AL, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Riliang","family":"Su","sequence":"additional","affiliation":[{"name":"Department of Electronic and Electrical Engineering, University of Strathclyde, Glasgow G1 1XW, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8538-2914","authenticated-orcid":false,"given":"David","family":"Lines","sequence":"additional","affiliation":[{"name":"Department of Electronic and Electrical Engineering, University of Strathclyde, Glasgow G1 1XW, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sivaram Nishal","family":"Ramadas","sequence":"additional","affiliation":[{"name":"Honeywell, Reddidtch B98 9ND, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"George","family":"Rowlands","sequence":"additional","affiliation":[{"name":"Department of Physics, University of Warwick, Coventry CV4 7AL, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Steve","family":"Dixon","sequence":"additional","affiliation":[{"name":"Department of Physics, University of Warwick, Coventry CV4 7AL, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,11,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Lynnworth, L.C. 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