{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,15]],"date-time":"2026-01-15T14:49:20Z","timestamp":1768488560026,"version":"3.49.0"},"reference-count":44,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2025,11,10]],"date-time":"2025-11-10T00:00:00Z","timestamp":1762732800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>To address challenges in holistic real-time condition monitoring of conventional wind tunnels\u2014caused by large structural dimensions and complex parameter monitoring\u2014this study proposes a wind tunnel condition monitoring surrogate model (POD-BPNN) integrating Proper Orthogonal Decomposition (POD) for data dimensionality reduction with Back Propagation Neural Networks (BPNNs). By implementing POD-based order reduction, the computational load for neural network training is significantly reduced while maintaining predictive accuracy through reduced-order data utilization. When applied to reconstruct stress\/displacement fields in a wind tunnel test section and the flow field in its fan section, the POD-BPNN model demonstrated prediction errors below 5% when validated against finite element and computational fluid dynamics simulations, with three orders of magnitude improvement in computational efficiency. This methodology satisfies precision and real-time requirements for structural\/fluid field monitoring in wind tunnels. When deployed with an existing health management system, online monitoring and predictive maintenance of the digital twin for the wind tunnel will be achievable.<\/jats:p>","DOI":"10.3390\/sym17111923","type":"journal-article","created":{"date-parts":[[2025,11,10]],"date-time":"2025-11-10T13:51:08Z","timestamp":1762782668000},"page":"1923","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["A Study on Real-Time Condition Monitoring Methods for Wind Tunnels Based on POD and BPNN"],"prefix":"10.3390","volume":"17","author":[{"given":"Yisheng","family":"Yang","sequence":"first","affiliation":[{"name":"State Key Lab of Digital Manufacturing Equipment and Technology, Huazhong University of Science and Technology, Wuhan 430070, China"},{"name":"Facility Design and Instrument Institute, China Aerodynamics Research and Development Center, Mianyang 621003, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Cheng","family":"Zhang","sequence":"additional","affiliation":[{"name":"Facility Design and Instrument Institute, China Aerodynamics Research and Development Center, Mianyang 621003, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ming","family":"Li","sequence":"additional","affiliation":[{"name":"Facility Design and Instrument Institute, China Aerodynamics Research and Development Center, Mianyang 621003, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hanwei","family":"Wang","sequence":"additional","affiliation":[{"name":"Suzhou Tongyuan Software & Control Technology Co., Ltd., Suzhou 215123, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiqiang","family":"Yan","sequence":"additional","affiliation":[{"name":"Facility Design and Instrument Institute, China Aerodynamics Research and Development Center, Mianyang 621003, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Miao","family":"Xian","sequence":"additional","affiliation":[{"name":"Suzhou Tongyuan Software & Control Technology Co., Ltd., Suzhou 215123, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hongqiang","family":"Xiong","sequence":"additional","affiliation":[{"name":"Suzhou Tongyuan Software & Control Technology Co., Ltd., Suzhou 215123, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sijie","family":"Yan","sequence":"additional","affiliation":[{"name":"State Key Lab of Digital Manufacturing Equipment and Technology, Huazhong University of Science and Technology, Wuhan 430070, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,11,10]]},"reference":[{"key":"ref_1","first-page":"19","article-title":"Key technology for mechanical design in large-scale cryogenic wind tunnel","volume":"36","author":"Lai","year":"2022","journal-title":"J. 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