Xiulong Yao¹, Mengge Yu^1,*, Jiali Liu², Qian Zhang¹

FDMP-Fluid Dynamics & Materials Processing, Vol.21, No.11, pp. 2795-2814, 2025, DOI:10.32604/fdmp.2025.072708 - 01 December 2025

Abstract High-speed trains operating in freezing rain are highly susceptible to severe ice accretion in the pantograph region, which compromises both power transmission efficiency and dynamic performance. To elucidate the underlying mechanisms of this phenomenon, an Euler–Euler multiphase flow model was employed to simulate droplet impingement and collection on the pantograph surface, while a glaze-ice formation model incorporating wall film dynamics was used to capture the subsequent growth of ice. The effects of key parameters—including liquid water content, ambient temperature, train velocity, and droplet diameter—on the amount and morphology of ice were systematically investigated. The results More >

Zheda Zhao, Tao Xu, Tong Yang, Yunpeng Wu^*, Fengxiang Guo^*

Structural Durability & Health Monitoring, Vol.19, No.6, pp. 1457-1472, 2025, DOI:10.32604/sdhm.2025.069611 - 17 November 2025

Abstract Utilizing unmanned aerial vehicle (UAV) photography to timely detect and evaluate potential safety hazards (PSHs) around high-speed rail has great potential to complement and reform the existing manual inspections by providing better overhead views and mitigating safety issues. However, UAV inspections based on manual interpretation, which heavily rely on the experience, attention, and judgment of human inspectors, still inevitably suffer from subjectivity and inaccuracy. To address this issue, this study proposes a lightweight hybrid learning algorithm named HDTA (hybrid dual tasks architecture) to automatically and efficiently detect the PSHs of UAV imagery. First, this HDTA… More >

Yang Lei^1,*, Bo Jiang¹, Yucai Zhao², Gaofeng Fu³, Falin Qi¹, Tian Tian¹, Qiankuan Feng¹, Qiming Qu¹

Structural Durability & Health Monitoring, Vol.19, No.6, pp. 1657-1679, 2025, DOI:10.32604/sdhm.2025.069415 - 17 November 2025

Abstract Detecting internal defects, particularly voids behind linings, is critical for ensuring the structural integrity of aging high-speed rail (HSR) tunnel networks. While ground-penetrating radar (GPR) is widely employed, systematic quantification of performance boundaries for air-coupled (A-CGPR) and ground-coupled (G-CGPR) systems within the complex electromagnetic environment of multilayer reinforced HSR tunnels remains limited. This study establishes physics-based quantitative performance limits for A-CGPR and G-CGPR through rigorously validated GPRMax finite-difference time-domain (FDTD) simulations and comprehensive field validation over a 300 m operational HSR tunnel section. Key performance metrics were quantified as functions of: (a) detection distance (A-CGPR:… More >

Xiaoyang Wu¹, Wenchao Han², Min Kuang^2,*, Xinqi Wang², Wenhao Xie²

FDMP-Fluid Dynamics & Materials Processing, Vol.21, No.9, pp. 2201-2223, 2025, DOI:10.32604/fdmp.2025.067081 - 30 September 2025

Abstract The dynamic behavior of high-speed craft navigating through variable sea states plays a pivotal role in ensuring maritime safety. However, many existing simulation approaches rely on linear or overly simplified representations of the marine environment, thereby limiting the fidelity of motion predictions. This study explores the motion characteristics of a 4.5-t high-speed vessel by conducting fully coupled numerical simulations using the STAR-CCM+ software. The analysis considers both calm and varying sea conditions, incorporating fluctuations in wave height, wavelength, and wind speed to reflect more realistic operating scenarios. Simulation results reveal that the vessel’s hydrodynamic response… More >

Yan Li¹, Bailong Sun², Tian Li^2,*, Weihua Zhang²

CMES-Computer Modeling in Engineering & Sciences, Vol.144, No.2, pp. 1957-1970, 2025, DOI:10.32604/cmes.2025.069159 - 31 August 2025

Abstract High-speed maglev trains represent a key direction for the future development of rail transportation. As operating speeds increase, they face increasingly severe aerodynamic challenges. The streamlined aerodynamic shape of a maglev train is a critical factor influencing its aerodynamic performance, and optimizing its length plays a significant role in improving the overall aerodynamic characteristics of the train. In this study, a numerical simulation model of a high-speed maglev train was established based on computational fluid dynamics (CFD) to investigate the effects of streamline length on the aerodynamic performance of the train operating on an open… More >

Ya Li^1,*, Min Deng², Shanyi Hao³, Yucong Lin¹, Yu Lu¹

FDMP-Fluid Dynamics & Materials Processing, Vol.21, No.7, pp. 1611-1622, 2025, DOI:10.32604/fdmp.2025.067497 - 31 July 2025

Abstract The noise generated by high-speed hair dryers significantly affects user experience, with aerodynamic design playing a crucial role in controlling sound emissions. This study investigates the aerodynamic noise characteristics of a commercial high-speed hair dryer through Computational Fluid Dynamics (CFD) analysis. The velocity field, streamline patterns, and vector distribution within the primary flow path and internal cavity were systematically examined. Results indicate that strong interactions between the wake flow generated by the guide vanes and the straight baffle in the rear flow path induce vortex structures near the outlet, which are primarily responsible for high-frequency More >

Yangyang Cao, Jiye Zhang^*, Jiawei Shi, Yao Zhang

FDMP-Fluid Dynamics & Materials Processing, Vol.21, No.5, pp. 1079-1098, 2025, DOI:10.32604/fdmp.2025.060429 - 30 May 2025

Abstract The pantograph area is a critical source of aerodynamic noise in high-speed trains, generating noise both directly and through its cavity, a factor that warrants considerable attention. One effective method for reducing aerodynamic noise within the pantograph cavity involves the introduction of a jet at the leading edge of the cavity. This study investigates the mechanisms driving cavity aerodynamic noise under varying jet velocities, using Improved Delayed Detached Eddy Simulation (IDDES) and Ffowcs Williams-Hawkings (FW-H) equations. The numerical simulations reveal that an increase in jet velocity results in a higher elevation of the shear layer… More >

Yingyong Zou^*, Xingkui Zhang, Tao Liu, Yu Zhang, Long Li, Wenzhuo Zhao

CMC-Computers, Materials & Continua, Vol.83, No.3, pp. 4699-4723, 2025, DOI:10.32604/cmc.2025.062625 - 19 May 2025

Abstract High-speed train engine rolling bearings play a crucial role in maintaining engine health and minimizing operational losses during train operation. To solve the problems of low accuracy of the diagnostic model and unstable model due to the influence of noise during fault detection, a rolling bearing fault diagnosis model based on cross-attention fusion of WDCNN and BILSTM is proposed. The first layer of the wide convolutional kernel deep convolutional neural network (WDCNN) is used to extract the local features of the signal and suppress the high-frequency noise. A Bidirectional Long Short-Term Memory Network (BILSTM) is… More >

Lanxi Zhang¹, Yuming Peng¹, Yudong Wu^2,*

FDMP-Fluid Dynamics & Materials Processing, Vol.21, No.1, pp. 205-220, 2025, DOI:10.32604/fdmp.2024.056516 - 24 January 2025

Abstract The challenge of aerodynamic noise is a key obstacle in the advancement of low-pressure tube ultra-high-speed maglev transportation, demanding urgent resolution. This study utilizes a broadband noise source model to perform a quantitative analysis of the aerodynamic noise produced by ultra-high-speed maglev trains operating in low-pressure environments. Initially, an external flow field calculation model for the ultra-high-speed maglev train is presented. Subsequently, numerical simulations based on the broadband noise source model are used to examine the noise characteristics. The impact of the train speed and pressure level on noise generation is investigated accordingly. Subsequently, a… More >

Linlin Sun^1,2, Zihui Wang³, Shukun Cui^1,2, Ziquan Yan^1,2,*, Weiping Hu³, Qingchun Meng³

CMES-Computer Modeling in Engineering & Sciences, Vol.142, No.1, pp. 555-577, 2025, DOI:10.32604/cmes.2024.056023 - 17 December 2024

Abstract Rail weld irregularities are one of the primary excitation sources for vehicle-track interaction dynamics in modern high-speed railways. They can cause significant wheel-rail dynamic interactions, leading to wheel-rail noise, component damage, and deterioration. Few researchers have employed the vehicle-track interaction dynamic model to study the dynamic interactions between wheel and rail induced by rail weld geometry irregularities. However, the cosine wave model used to simulate rail weld irregularities mainly focuses on the maximum value and neglects the geometric shape. In this study, novel theoretical models were developed for three categories of rail weld irregularities, based… More >