3A22 Modelling of seated passenger on high speed railway vehicle by multi-body dynamics(Customer Environment)

This paper deals with the issue of dynamic effects of a high-speed railway vehicle on the track. Some aspects of vehicle/track interaction at higher speeds are described. In this context, a multi-body model of high-speed railway vehicle was created and several simulation scenarios were performed with this model. Furthermore, the simulations were evaluated with a focus on selected characteristics of the vehicle/track interaction.

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Dynamic Performance of High-Speed Electric Multiple Unit within Multi-Body System Simulation

Recent Patents on Mechanical Engineering ◽

10.2174/2666145412666190923104415 ◽

2019 ◽

Vol 12 (4) ◽

pp. 339-349

Author(s):

Junguo Wang ◽

Daoping Gong ◽

Rui Sun ◽

Yongxiang Zhao

Keyword(s):

High Speed ◽

Rapid Development ◽

Dynamic Performance ◽

Body System ◽

High Speed Railway ◽

Evaluation Indexes ◽

Actual Operation ◽

Multiple Unit ◽

The Stability ◽

Multi Body

Background: With the rapid development of the high-speed railway, the dynamic performance such as running stability and safety of the high-speed train is increasingly important. This paper focuses on the dynamic performance of high-speed Electric Multiple Unit (EMU), especially the dynamic characteristics of the bogie frame and car body. Various patents have been discussed in this article. Objective: To develop the Multi-Body System (MBS) model of EMU, verify whether the dynamic performance meets the actual operation requirements, and provide some useful information for dynamics and structural design of the proposed EMU. Methods: According to the technical characteristics of a typical EMU, a MBS model is established via SIMPACK, and the measured data of China high-speed railway is taken as the excitation of track random irregularity. To test the dynamic performance of the EMU, including the stability and safety, some evaluation indexes such as wheel-axle lateral forces, wheel-axle lateral vertical forces, derailment coefficients and wheel unloading rates are also calculated and analyzed in detail. Results: The MBS model of EMU has better dynamic performance especially curving performance, and some evaluation indexes of the stability and safety have also reached China’s high-speed railway standards. Conclusion: The effectiveness of the proposed MBS model is verified, and the dynamic performance of the MBS model can meet the design requirements of high-speed EMU.

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Research on Bogie Frame Lateral Instability of High-Speed Railway Vehicle

Shock and Vibration ◽

10.1155/2018/8469143 ◽

2018 ◽

Vol 2018 ◽

pp. 1-13

Author(s):

Chen Wang ◽

Shihui Luo ◽

Ziqiang Xu ◽

Chang Gao ◽

Weihua Ma

Keyword(s):

High Speed ◽

Dynamics Simulation ◽

Lateral Acceleration ◽

Railway Vehicle ◽

Lateral Instability ◽

Bogie Frame ◽

High Speed Railway ◽

Long Time ◽

Line Test ◽

Equivalent Conicity

In order to find out the reason for the bogie frame instability alarm in the high-speed railway vehicle, the influence of wheel tread profile of the unstable vehicle was investigated. By means of wheel-rail contact analysis and dynamics simulation, the effect of tread wear on the bogie frame lateral stability was studied. The result indicates that the concave wear of tread is gradually aggravated with the increase of operation mileage; meanwhile the wheel-rail equivalent conicity also increases. For the rail which has not been grinded for a long time, the wear of gauge corner and wide-worn zone is relatively severe; the matching equivalent conicity is 0.31-0.4 between the worn rail and the concave-worn-tread wheel set. The equivalent conicity between the grinded rail and the concave-worn tread is below 0.25; the equivalent conicities are always below 0.1 between the reprofiled wheel set and various rails. The result of the line test indicates that the lateral acceleration of bogie frame corresponding to the worn wheel-rail can reach 8.5m/s2, and the acceleration after the grinding is reduced below 4.5m/s2. By dynamics simulation, it turns out that the unreasonable wheel-rail matching relationship is the major cause of the bogie frame lateral alarm. With the tread-concave wear being aggravated, the equivalent conicity of wheel-rail matching constantly increases, which leads to the bogie frame lateral instability and then the frame instability alarm.

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Modelling and evaluation of the hunting behaviour of a high-speed railway vehicle on curved track

Proceedings of the Institution of Mechanical Engineers Part F Journal of Rail and Rapid Transit ◽

10.1177/0954409718789531 ◽

2018 ◽

Vol 233 (2) ◽

pp. 220-236 ◽

Cited By ~ 3

Author(s):

Vivek Kumar ◽

Vikas Rastogi ◽

PM Pathak

Keyword(s):

High Speed ◽

Degrees Of Freedom ◽

Critical Speed ◽

Transportation Network ◽

Graph Model ◽

Railway Vehicle ◽

Physical Damage ◽

Creep Theory ◽

High Speed Railway ◽

Hunting Behaviour

Nowadays, rail transport is a very important part of the transportation network for any countries. The demand for high operational speed makes hunting a very common instability problem in railway vehicles. Hunting leads to discomfort and causes physical damage to carriage components, such as wheels, rails, etc. The causes of instability and derailment should be identified and eliminated at the designing stage of a train to ensure its safe operation. In most of the earlier studies on hunting behaviour, a simplified model with a lower degree of freedom were considered, which resulted in incorrect results in some instances. In this study, a complete bond graph model of a railway vehicle with 31 degrees of freedom is presented to determine the response of a high-speed railway vehicle. For this purpose, two wheel–rail contacts grounded on a flange contact and Kalker’s linear creep theory are implemented. The model is simulated to observe the effects of suspension elements on the vehicle’s critical hunting velocity. It is observed that the critical hunting speed is extremely sensitive to the primary longitudinal and lateral springs. Other primary and secondary springs and dampers also affect the critical speed to some extent. However, the critical hunting velocity is insensitive to vertical suspension elements for both the primary and secondary suspensions. Also, the critical speed is found to be inversely related to the conicity of the wheel.

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Improved backward fatigue statistical inference to the high-speed railway vehicle components

Procedia Structural Integrity ◽

10.1016/j.prostr.2020.01.027 ◽

2019 ◽

Vol 22 ◽

pp. 211-218

Author(s):

S.C. Wu ◽

C.H. Li ◽

G.Z. Kang ◽

L.Y. Xie ◽

W.H. Zhang

Keyword(s):

Statistical Inference ◽

High Speed ◽

Railway Vehicle ◽

High Speed Railway ◽

Vehicle Components

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Analysis on Impact Loading at Rail Welds at High Speed

Volume 2: Automotive Systems; Bioengineering and Biomedical Technology; Computational Mechanics; Controls; Dynamical Systems ◽

10.1115/esda2008-59383 ◽

2008 ◽

Cited By ~ 1

Author(s):

Guangwen Xiao ◽

Xinbiao Xiao ◽

Zefeng Wen ◽

Xuesong Jin

Keyword(s):

Impact Loading ◽

High Speed ◽

Hertzian Contact ◽

Railway Vehicle ◽

Vehicle Speed ◽

Explicit Integration ◽

Normal Forces ◽

Rail Irregularity ◽

Multi Body ◽

The Impact

When a railway vehicle passes through a track with different weld irregularities at high speed, the impact loading of the vehicle coupled with the track is investigated in detail using a coupled vehicle/track model. In this model, a half vehicle is considered and modeled as a multi-body system. In the track model, a Timoshenko beam resting on discrete sleepers is applied to model each rail. Each sleeper is modeled as a rigid body accounting for its vertical, lateral, roll motions. A moving sleeper support model is used to simulate the interaction of the vehicle and the track. The ballast bed is replaced with equivalent masses. The equivalent dampers and springs are used to replace the connections between the parts of the vehicle and track. In calculating the coupled vehicle and track dynamics, Hertzian contact theory and the creep force theory by Shen et al. are, respectively, used to calculate the normal forces and the creep forces between the wheels and the rails. The motion equations of the vehicle-track are solved by means of an explicit integration method. The weld rail irregularity is modeled by setting a local track vertical deviation at a rail weld joint, which is described with a simplified cosine function. In the numerical analysis the effect of the different wavelength, depth, the position of the welded joint in a sleeper span, and vehicle speed is taken into account. The numerical results obtained are greatly useful in the tolerance design of welded rail profile irregularity caused by damage and hand-grinding after rail welding.

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