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The equipment cabins of high‐speed trains encountered alternating pressure loads during operation. A fatigue evaluation methodology based on sub‐zone aerodynamic loading was proposed. Theoretical model was given between pressure load at each zone and the accompanying six structural stress components. Stress recovery matrix was formulated by finite element analysis (FEA) in sub‐zone loading cases to relate the stress to the measured pressure loads. Vehicle test gathered the pressure time‐history data of cabin sub‐zones at the head car in different ambient conditions, from which the two‐dimensional stress spectrum was derived by rain‐flow counting. The fatigue damage of welds was then assessed utilizing the Miner's and Corten Dolan's rules, yielding maximum equivalent damages of 0.72 and 0.23, respectively. The structural fatigue damage under high environmental wind conditions was 1–3 times greater than in calm weather. Nonetheless, the fatigue damage incurred by the metal matrix was significantly lower, demonstrating a substantial safety margin. Highlights: Proposed a sub‐zone aerodynamic load‐stress conversion model.Welds exhibit higher aerodynamic fatigue damage than metal matrix.Strong winds heighten fatigue damage in the equipment cabin of high‐speed trains. [ABSTRACT FROM AUTHOR]

With the increase in train speed, the aerodynamics in tunnels is emerging. In recent years, we have carried out a few full-scale tests about tunnel aerodynamics, and the law of influence of train speed on pressure change, airflow velocity, and micropressure wave are obtained, and a passenger comfort survey was conducted. When a high-speed train enters a tunnel at 200 km/h, the pressure change amplitude and pressure change per second inside the vehicle are 1,036 Pa and 273 Pa/s, respectively, and 88.9% people experienced no obvious discomfort; the airflow velocity in the tunnel is 14.8 m/s, which exceeds the criterion, 14 m/s. Therefore, it is suggested that workers should not work in the tunnel when a train passes; because the micropressure wave is only 9.7 Pa at the measured point, 20 m from the exit port of tunnel, the tunnel has a cross section enlarged hood with windows, and the passing train does not impact the environment near the tunnel. DOI: 10.1061/(ASCE)TE.1943-5436.0000146 CE Database subject headings: Railroad trains; Tunnels: Aerodynamics; Air flow. Author keywords: Train: Tunnel; Aerodynamics; Pressure change; Air flow; Micropressure wave.

In this study, based on the shear-stress transport κ–ω turbulent model, the improved delayed detached eddy simulation method has been used to simulate the unsteady aerodynamic performance of trains with different obstacle deflectors at two yaw angles (0° and 15°). The numerical algorithm is used and some of the numerical results are verified through wind tunnel tests. By comparing and analysing the obtained results, the effects of the obstacle deflectors on the force of the trains as well as the pressure and flow structure around the trains are elucidated. The results show that the obstacle deflectors primarily affect the flow field at the bottom of the head car as well as the wake flow, and that the internal oblique-type obstacle deflector (IOOD) markedly improves the aerodynamic performance of the trains, by decreasing most of the aerodynamic forces of the train cars and minimising their fluctuations. Further, a nonzero yaw angle weakens or even changes the effect of the IOOD on the aerodynamic forces of the train cars. However, the effect of the IOOD is more on the tail car. [ABSTRACT FROM AUTHOR]

By using numerical calculation method, 2-car high-speed train going through the station or intersecting at the station at the different speed was simulated. The bow lift change, influence of pantograph state and barrier door on pantograph lift change was researched. Results indicate that, during the train coming into the platform or going out of it, the fluctuation of pantograph lift is significant. When the train going through the platform, lift change of pantograph bow and upper frame is the biggest. There is a linear relationship between pantograph bow and the power of speed, and the law is not changed by pantograph state. Lift change of pantograph bow in the state of adverse pantograph is greater than it in the state of favorable pantograph, and influence of barrier door on the pantograph lift change is limited. When two trains are passing each other through the platform, distribution of lift change of pantograph components and law of lift change with train speed are changed significantly by pantograph state. Influence of barrier door on the pantograph lift change is more obvious than one of the train going through platform. The meeting position in the station has no effect on the lift change of pantograph. Lift change of pantograph is affected obviously by non-uniformity of train passing. [ABSTRACT FROM AUTHOR]

Aerodynamic noise of high-speed train connection section with different parameters were simulated numerically adopting LES model companied with acoustic analogy and reduction improvement project was proposed. The aerodynamic noise distribution of high-speed train connection section at speed of 300km/h was obtained from the research, the results show that aerodynamic noise is a kind of wide frequency noise which exits in wide frequency band. The acoustic pressure amplitude of every test point is bigger at low frequency, increasing firstly then decreasing with the increase of frequency, and acoustic pressure level within 1/3 octave band frequency concentrates in the rage of 315~1000Hz; Among different parameters of train connection section, the acoustic pressure level amplitude increases with the increase of groove length and height; Compared with the project without windshield, the noise reduction effect of full windshield project is apparent, avoiding severe disturbance flow effectively, the average acoustic pressure level reductive amplitude is 9.4% and the average total acoustic pressure level reductive amplitude is 4.27dBA. All these researches provide scientific foundation to the initial design of high-speed train with low noise. [ABSTRACT FROM AUTHOR]