{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T11:16:22Z","timestamp":1787829382270,"version":"build-2784847793"},"reference-count":31,"publisher":"Public Library of Science (PLoS)","issue":"6","license":[{"start":{"date-parts":[[2025,6,25]],"date-time":"2025-06-25T00:00:00Z","timestamp":1750809600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"China State Railway Group Co., Ltd.","award":["K2024X013(JB)"],"award-info":[{"award-number":["K2024X013(JB)"]}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:p>Numerical simulations of railway air brake systems are becoming increasingly computationally demanding due to the growing complexity and length of trains. This study introduces a parallel computing-enhanced model for simulating pressure dynamics in heavy-haul trains. The proposed approach assigns dedicated threads to each vehicle, with additional threads managing the interface fluxes of brake pipe connections, and is implemented in C# using the ThreadPool and Parallel libraries. A train configuration consisting of one locomotive and 116 vehicles was simulated under various brake pipe pressure reduction conditions. The validity of the air braking system simulation model was confirmed through comparisons with experimental data. Furthermore, the impact of parallel computing on simulation efficiency was investigated. The results indicate that the efficiency of serial computing is primarily influenced by the CPU Boost Clock frequency. Parallel computing consistently outperforms serial computing, with speedup ratios increasing as the number of CPU threads grows. Although the simulation partitions tasks by vehicle units, the computations remain sufficiently fine-grained that the ThreadPool implementation outperforms the Parallel library, as it eliminates the dynamic scheduling overhead inherent to Parallel\u2019s workload distribution mechanism. Additionally, parallel computing efficiency improves as the number of vehicles increases; however, beyond a certain threshold, efficiency stabilizes as workload distribution becomes fully optimized.<\/jats:p>","DOI":"10.1371\/journal.pone.0326844","type":"journal-article","created":{"date-parts":[[2025,6,25]],"date-time":"2025-06-25T17:51:07Z","timestamp":1750873867000},"page":"e0326844","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":1,"title":["Numerical simulation and parallel implementation of freight train air brake system"],"prefix":"10.1371","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0009-0003-5914-2361","authenticated-orcid":true,"given":"Zongze","family":"Yu","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7563-150X","authenticated-orcid":true,"given":"Yuguang","family":"Wei","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chuxuan","family":"Hu","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2025,6,25]]},"reference":[{"issue":"1","key":"pone.0326844.ref001","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1080\/23248378.2021.2006808","article-title":"Freight train air brake models","volume":"11","author":"Q Wu","year":"2021","journal-title":"Int J Rail Transportation"},{"issue":"4","key":"pone.0326844.ref002","doi-asserted-by":"crossref","first-page":"480","DOI":"10.1080\/00423114.2016.1251599","article-title":"Braking induced impact for train to train rescue","volume":"55","author":"L Wei","year":"2016","journal-title":"Vehicle System Dynamics"},{"issue":"8","key":"pone.0326844.ref003","article-title":"The Effect of a Variable Disc Pad Friction Coefficient for the Mechanical Brake System of a Railway Vehicle","volume":"10","author":"N-J Lee","year":"2015","journal-title":"PLoS One"},{"issue":"1","key":"pone.0326844.ref004","doi-asserted-by":"crossref","first-page":"154","DOI":"10.2174\/1874447802014010154","article-title":"Comparisons Between Braking Experiments and Longitudinal Train Dynamics Using Friction Coefficient and Braking Pressure Modeling in a Freight Train","volume":"14","author":"DB Choi","year":"2020","journal-title":"TOTJ"},{"key":"pone.0326844.ref005","doi-asserted-by":"crossref","first-page":"176","DOI":"10.1504\/IJVSMT.2010.037125","article-title":"Effects of the power unit location on in-train longitudinal forces during brake application","volume":"5","author":"S Mohammadi","year":"2010","journal-title":"IJVSMT"},{"issue":"2","key":"pone.0326844.ref006","doi-asserted-by":"crossref","first-page":"192","DOI":"10.1080\/00423114.2018.1456667","article-title":"Influence of train length on in-train longitudinal forces during brake application","volume":"57","author":"R Serajian","year":"2018","journal-title":"Vehicle System Dynamics"},{"issue":"6","key":"pone.0326844.ref007","doi-asserted-by":"crossref","first-page":"523","DOI":"10.1243\/09544097JRRT306","article-title":"The Effects of Train Brake Delay Time on In-Train Forces","volume":"224","author":"A Nasr","year":"2010","journal-title":"Proceedings of the Institution of Mechanical Engineers, Part F: J Rail and Rapid Transit"},{"key":"pone.0326844.ref008","article-title":"Modelling and analysis of thermal and stress loads in train disc brakes - braking from 250 km\/h to standstill","volume":"55","author":"G Oder","year":"2009","journal-title":"Strojniski Vestn"},{"issue":"21","key":"pone.0326844.ref009","doi-asserted-by":"crossref","first-page":"4846","DOI":"10.3390\/ma13214846","article-title":"A Comparison of 3D and 2D FE Frictional Heating Models for Long and Variable Applications of Railway Tread Brake","volume":"13","author":"M Kuciej","year":"2020","journal-title":"Materials (Basel)"},{"key":"pone.0326844.ref010","doi-asserted-by":"crossref","unstructured":"Cantone L, M\u00fcller L, Negretti D, Vullo V. 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