{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,24]],"date-time":"2026-03-24T06:58:09Z","timestamp":1774335489178,"version":"3.50.1"},"reference-count":28,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2024,9,23]],"date-time":"2024-09-23T00:00:00Z","timestamp":1727049600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Nature Science of China","award":["52205581"],"award-info":[{"award-number":["52205581"]}]},{"name":"National Nature Science of China","award":["2023M734285"],"award-info":[{"award-number":["2023M734285"]}]},{"name":"China Postdoctoral Science Foundation","award":["52205581"],"award-info":[{"award-number":["52205581"]}]},{"name":"China Postdoctoral Science Foundation","award":["2023M734285"],"award-info":[{"award-number":["2023M734285"]}]},{"name":"China Academy of Aero-engine","award":["52205581"],"award-info":[{"award-number":["52205581"]}]},{"name":"China Academy of Aero-engine","award":["2023M734285"],"award-info":[{"award-number":["2023M734285"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Given the increasing application of eddy current sensors for measuring turbine tip clearance in aero engines, enhancing the performance of these sensors is essential for improving measurement accuracy. This study investigates the influence of coil shape on the measurement performance of planar eddy current sensors and identifies an optimal coil shape to enhance sensing capabilities. To achieve this, various coil shapes\u2014specifically circular, square, rectangular wave, and triangular wave\u2014were designed and fabricated, featuring different numbers of turns for the experiment at room temperature. By employing a method for calculating coil inductance, the performance of each sensor was evaluated based on key metrics: measurement range, sensitivity, and linearity. Experimental results reveal that the square coil configuration outperforms other shapes in overall measurement performance. Notably, the square coil demonstrated a measurement range of 0 mm to 8 mm, a sensitivity of 0.115685 \u03bcH\/mm, and an impressive linearity of 98.41% within the range of 0 mm to 2 mm. These findings indicate that the square coil configuration enhances measurement capabilities. The conclusions drawn from this study provide valuable insights for selecting coil shapes and optimizing the performance of planar eddy current sensors, thereby contributing to the advancement of turbine tip clearance measurement techniques in aero engines.<\/jats:p>","DOI":"10.3390\/s24186133","type":"journal-article","created":{"date-parts":[[2024,9,24]],"date-time":"2024-09-24T08:56:06Z","timestamp":1727168166000},"page":"6133","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Experimental Investigation on the Effect of Coil Shape on Planar Eddy Current Sensor Characteristic for Blade Tip Clearance"],"prefix":"10.3390","volume":"24","author":[{"given":"Lingqiang","family":"Zhao","sequence":"first","affiliation":[{"name":"School of Power and Energy, Northwestern Polytechnical University, Youyi West Road 127#, Xi\u2019an 710054, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2336-0503","authenticated-orcid":false,"given":"Yaguo","family":"Lyu","sequence":"additional","affiliation":[{"name":"School of Power and Energy, Northwestern Polytechnical University, Youyi West Road 127#, Xi\u2019an 710054, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fulin","family":"Liu","sequence":"additional","affiliation":[{"name":"School of Power and Energy, Northwestern Polytechnical University, Youyi West Road 127#, Xi\u2019an 710054, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhenxia","family":"Liu","sequence":"additional","affiliation":[{"name":"School of Power and Energy, Northwestern Polytechnical University, Youyi West Road 127#, Xi\u2019an 710054, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5239-3323","authenticated-orcid":false,"given":"Ziyu","family":"Zhao","sequence":"additional","affiliation":[{"name":"Xi\u2019an Research Institute of High-Tech, Xi\u2019an 710054, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,9,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"154","DOI":"10.1115\/1.3227244","article-title":"Rotor-tip Leakage: Part I\u2014Basic Methodology","volume":"104","author":"Booth","year":"1982","journal-title":"J. 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