{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,8]],"date-time":"2026-06-08T14:10:22Z","timestamp":1780927822185,"version":"3.54.1"},"reference-count":36,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2022,7,1]],"date-time":"2022-07-01T00:00:00Z","timestamp":1656633600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Natural Science Foundation of China","award":["12002115"],"award-info":[{"award-number":["12002115"]}]},{"name":"National Natural Science Foundation of China","award":["F2020402005"],"award-info":[{"award-number":["F2020402005"]}]},{"name":"National Natural Science Foundation of China","award":["QN2020181"],"award-info":[{"award-number":["QN2020181"]}]},{"name":"National Natural Science Foundation of China","award":["19422101008-8"],"award-info":[{"award-number":["19422101008-8"]}]},{"name":"Natural Science Foundation of Hebei Province","award":["12002115"],"award-info":[{"award-number":["12002115"]}]},{"name":"Natural Science Foundation of Hebei Province","award":["F2020402005"],"award-info":[{"award-number":["F2020402005"]}]},{"name":"Natural Science Foundation of Hebei Province","award":["QN2020181"],"award-info":[{"award-number":["QN2020181"]}]},{"name":"Natural Science Foundation of Hebei Province","award":["19422101008-8"],"award-info":[{"award-number":["19422101008-8"]}]},{"name":"Scientific and Technological Research Projects of Universities in Hebei Province","award":["12002115"],"award-info":[{"award-number":["12002115"]}]},{"name":"Scientific and Technological Research Projects of Universities in Hebei Province","award":["F2020402005"],"award-info":[{"award-number":["F2020402005"]}]},{"name":"Scientific and Technological Research Projects of Universities in Hebei Province","award":["QN2020181"],"award-info":[{"award-number":["QN2020181"]}]},{"name":"Scientific and Technological Research Projects of Universities in Hebei Province","award":["19422101008-8"],"award-info":[{"award-number":["19422101008-8"]}]},{"name":"Science and Technology Research and Development Project of Handan City","award":["12002115"],"award-info":[{"award-number":["12002115"]}]},{"name":"Science and Technology Research and Development Project of Handan City","award":["F2020402005"],"award-info":[{"award-number":["F2020402005"]}]},{"name":"Science and Technology Research and Development Project of Handan City","award":["QN2020181"],"award-info":[{"award-number":["QN2020181"]}]},{"name":"Science and Technology Research and Development Project of Handan City","award":["19422101008-8"],"award-info":[{"award-number":["19422101008-8"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The low energy conversion efficiency of electromagnetic acoustic transducers (EMATs) is a critical issue in nondestructive testing applications. To overcome this shortcoming, a butterfly coil EMAT was developed and optimized by numerical simulation based on a 2\u2212D finite element model. First, the effect of the structural parameters of the butterfly coil EMAT was investigated by orthogonal test theory. Then, a modified butterfly coil EMAT was designed that consists of three\u2212square permanent magnets with opposite polarity (TSPM\u2212OP) to enhance the signal amplitude. Finally, the signal amplitude obtained from the three types of EMATs, that is, the traditional EMAT, the EMAT optimized by orthogonal test theory, and the modified EMAT with TSPM\u2212OP, were analyzed and compared. The results show that the signal amplitude achieved by the modified butterfly coil EMAT with TSPM\u2212OP can be increased by 4.97 times compared to the traditional butterfly coil EMAT.<\/jats:p>","DOI":"10.3390\/s22134985","type":"journal-article","created":{"date-parts":[[2022,7,4]],"date-time":"2022-07-04T20:59:18Z","timestamp":1656968358000},"page":"4985","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":30,"title":["Numerical Study and Optimal Design of the Butterfly Coil EMAT for Signal Amplitude Enhancement"],"prefix":"10.3390","volume":"22","author":[{"given":"Jingjun","family":"Zhang","sequence":"first","affiliation":[{"name":"College of Mechanical and Equipment Engineering, Hebei University of Engineering, Handan 056038, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Min","family":"Liu","sequence":"additional","affiliation":[{"name":"College of Mechanical and Equipment Engineering, Hebei University of Engineering, Handan 056038, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4653-5030","authenticated-orcid":false,"given":"Xiaojuan","family":"Jia","sequence":"additional","affiliation":[{"name":"College of Mechanical and Equipment Engineering, Hebei University of Engineering, Handan 056038, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ruizhen","family":"Gao","sequence":"additional","affiliation":[{"name":"College of Mechanical and Equipment Engineering, Hebei University of Engineering, Handan 056038, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,7,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Shaloo, M., Schnall, M., Klein, T., Huber, N., and Reitinger, B. 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