{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,28]],"date-time":"2026-09-28T18:44:06Z","timestamp":1790621046000,"version":"4.1.0"},"reference-count":18,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2024,12,4]],"date-time":"2024-12-04T00:00:00Z","timestamp":1733270400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"U.S. Department of Energy Funded Lab"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Ultrasound is an excellent way to acquire data that reveal useful information about systems operating in harsh environments, which may include elevated temperature, ionizing radiation, and aggressive chemicals. The effects of harsh environments on piezoelectric materials have been studied in much more depth than the other aspects of ultrasonic transducers used in pulse-echo mode. Therefore, finite element simulations and laboratory experiments are used to demonstrate the unique characteristics of pulse-echo immersion testing. Using an aluminum nitride piezoelectric element mounted on a vessel wall, characteristics associated with electrode thickness, couplant, backing material, and an acoustic matching layer are investigated. Considering a wave path through a vessel wall and into a fluid containing a target, when the travel distance in the fluid is relatively short, it can be difficult to discern the target echo from the reverberations in the vessel wall. When an acoustic matching layer between the vessel wall and the fluid does not suffice, a simple subtractive signal-processing method can minimize the reverberations, leaving just the target echoes of interest. Simulations and experiments demonstrate that sufficient target echoes are detected to determine the time of flight. Furthermore, a simple disc-like surface anomaly on the target is detectable.<\/jats:p>","DOI":"10.3390\/s24237748","type":"journal-article","created":{"date-parts":[[2024,12,4]],"date-time":"2024-12-04T10:07:10Z","timestamp":1733306830000},"page":"7748","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Unique Characteristics of Pulse-Echo Sensing Systems for Ultrasonic Immersion Testing in Harsh Environments"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7365-887X","authenticated-orcid":false,"given":"Gaofeng","family":"Sha","sequence":"first","affiliation":[{"name":"Department of Engineering Science and Mechanics, Penn State, University Park, PA 16802, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrew R.","family":"Bozek","sequence":"additional","affiliation":[{"name":"Department of Engineering Science and Mechanics, Penn State, University Park, PA 16802, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2136-6346","authenticated-orcid":false,"given":"Bernhard R.","family":"Tittmann","sequence":"additional","affiliation":[{"name":"Department of Engineering Science and Mechanics, Penn State, University Park, PA 16802, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3396-993X","authenticated-orcid":false,"given":"Cliff J.","family":"Lissenden","sequence":"additional","affiliation":[{"name":"Department of Engineering Science and Mechanics, Penn State, University Park, PA 16802, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,12,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"232901","DOI":"10.1063\/1.3524192","article-title":"High Temperature Ultrasonic Transducer up to 1000 C Using Lithium Niobate Single Crystal","volume":"97","author":"Baba","year":"2010","journal-title":"Appl. Phys. Lett."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"533","DOI":"10.1109\/TNS.2017.2775163","article-title":"Irradiation Testing of Piezoelectric (Aluminum Nitride, Zinc Oxide, and Bismuth Titanate) and Magnetostrictive Sensors (Remendur and Galfenol)","volume":"65","author":"Reinhardt","year":"2018","journal-title":"IEEE Trans. Nucl. Sci."},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Tittmann, B.R., Batista, C., Trivedi, Y., Lissenden, C., and Reinhardt, B. (2019). State-of-the-Art and Practical Guide to Ultrasonic Transducers for Harsh Environments Including Temperatures above 2120 \u00b0F (1000 \u00b0C) and Neutron Flux above 1013 n\/cm2. Sensors, 19.","DOI":"10.3390\/s19214755"},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Kazys, R., and Vaskeliene, V. (2021). High Temperature Ultrasonic Transducers: A Review. Sensors, 21.","DOI":"10.3390\/s21093200"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"35","DOI":"10.1016\/j.nimb.2020.08.018","article-title":"Impact of Nuclear Reactor Radiation on the Performance of AlN\/Sapphire Surface Acoustic Wave Devices","volume":"481","author":"Wang","year":"2020","journal-title":"Nucl. Instrum. Methods Phys. Res. Sect. B Beam Interact. Mater. At."},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Griffin, J.W., Peters, T.J., Posakony, G.J., Chien, H.-T., Bond, L.J., Denslow, K.M., Sheen, S.-H., and Raptis, P. (2009). Under-Sodium Viewing: A Review of Ultrasonic Imaging Technology for Liquid Metal Fast Reactors, Pacific Northwest National Lab.. PNNL-18292.","DOI":"10.2172\/1010482"},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Korsah, K., Ramuhalli, P., Vlim, R., Kisner, R.A., Britton, C.L., Wootan, D.W., Anheier, N.C., Diaz, A.A., Hirt, E.H., and Chien, H.T. (2016). Assessment of Sensor Technologies for Advanced Reactors, Oak Ridge National Laboratory. ORNL\/TM--2016\/337.","DOI":"10.2172\/1345781"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1880","DOI":"10.1109\/TUFFC.2015.007252","article-title":"High-Temperature Electromechanical Characterization of AlN Single Crystals","volume":"62","author":"Kim","year":"2015","journal-title":"IEEE Trans. Ultrason. Ferroelectr. Freq. Control"},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Giurgiutiu, V. (2007). Structural Health Monitoring with Piezoelectric Wafer Active Sensors, Academic Press.","DOI":"10.1016\/B978-012088760-6.50008-8"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"060008","DOI":"10.1063\/1.5099798","article-title":"Field Deployable Spray-on Ultrasonic Coatings for High-Temperature Applications","volume":"2102","author":"Trivedi","year":"2019","journal-title":"AIP Conf. Proc."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"225","DOI":"10.1016\/S0963-8695(98)00045-0","article-title":"Modeling Elastic Wave Propagation in Waveguides with the Finite Element Method","volume":"32","author":"Moser","year":"1999","journal-title":"NDT E Int."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"045014","DOI":"10.1088\/1361-665X\/aab162","article-title":"Modeling Guided Wave Excitation in Plates with Surface Mounted Piezoelectric Elements: Coupled Physics and Normal Mode Expansion","volume":"27","author":"Ren","year":"2018","journal-title":"Smart Mater. Struct."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"269","DOI":"10.1134\/S1061830921040094","article-title":"Investigation of the Performance of a Piezoelectric Ultrasonic Transducer by Finite Element Modeling","volume":"57","author":"Honarvar","year":"2021","journal-title":"Russ. J. Nondestruct. Test."},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Twiefel, J., Glukhovkoy, A., de Wall, S., Wurz, M.C., Sehlmeyer, M., Hitzemann, M., and Zimmermann, S. (2021). Towards a Highly Sensitive Piezoelectric Nano-Mass Detection\u2014A Model-Based Concept Study. Sensors, 21.","DOI":"10.3390\/s21072533"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"23","DOI":"10.1080\/09349847.2014.934575","article-title":"Bonding Piezoelectric Wafers for Application in Structural Health Monitoring-Adhesive Selection","volume":"26","author":"Mustapha","year":"2015","journal-title":"Res. Nondestruct. Eval."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"55","DOI":"10.1016\/0022-5096(90)90021-U","article-title":"Diffusivity of Ultrasound in Polycrystals","volume":"38","author":"Weaver","year":"1990","journal-title":"J. Mech. Phys. Solids"},{"key":"ref_17","doi-asserted-by":"crossref","unstructured":"Rathod, V.T. (2020). A Review of Acoustic Impedance Matching Techniques for Piezoelectric Sensors and Transducers. Sensors, 20.","DOI":"10.3390\/s20144051"},{"key":"ref_18","first-page":"041012","article-title":"A Development Strategy for Structural Health Monitoring Applications","volume":"4","author":"Cawley","year":"2021","journal-title":"J. Nondestruct. Eval. Diagn. Progn. Eng. Syst."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/24\/23\/7748\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T16:46:32Z","timestamp":1760114792000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/24\/23\/7748"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,12,4]]},"references-count":18,"journal-issue":{"issue":"23","published-online":{"date-parts":[[2024,12]]}},"alternative-id":["s24237748"],"URL":"https:\/\/doi.org\/10.3390\/s24237748","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2024,12,4]]}}}