A spatial coupling model to study dynamic performance of pantograph-catenary with vehicle-track excitation

The wind-induced vibration of the high-speed catenary and the dynamic behaviour of the pantograph–catenary under stochastic wind field are firstly analysed. The catenary model is established based on nonlinear cable and truss elements, which can fully describe the nonlinearity of each wire and the initial configuration. The model of the aerodynamic forces acting on the messenger/contact wire is deduced by considering the effect of the vertical and horizontal fluctuating winds. The vertical and horizontal fluctuating winds are simulated by employing the Davenport and Panofsky spectrums, respectively. The aerodynamic coefficients of the contact/messenger wire are calculated through computational fluid dynamics. The wind-induced vibration response of catenary is analysed with different wind speeds and angles. Its frequency-domain characteristics are discussed using Auto Regression model. Finally, a pantograph model is introduced and the contact force of the pantograph–catenary under stochastic wind i...

Nonlinear analysis of wind-induced vibration of high-speed railway catenary and its influence on pantograph–catenary interaction

Active control of contact force for high-speed railway pantograph-catenary based on multi-body pantograph model

Due to the intrinsic nonlinear characteristics and complex structure of the high-speed catenary system, a modelling method is proposed based on the analytical expressions of nonlinear cable and truss elements. The calculation procedure for solving the initial equilibrium state is proposed based on the Newton–Raphson iteration method. The deformed configuration of the catenary system as well as the initial length of each wire can be calculated. Its accuracy and validity of computing the initial equilibrium state are verified by comparison with the separate model method, absolute nodal coordinate formulation and other methods in the previous literatures. Then, the proposed model is combined with a lumped pantograph model and a dynamic simulation procedure is proposed. The accuracy is guaranteed by the multiple iterative calculations in each time step. The dynamic performance of the proposed model is validated by comparison with EN 50318, the results of the finite element method software and SIEMENS simulati...

Nonlinear modelling of high-speed catenary based on analytical expressions of cable and truss elements

Disc brake system is one of the most critical components in a vehicle, which is always exposed to nonlinear transient thermoelastic conditions. Optimal design of a brake system to suit the heat transfer, weight and packing requirements is an ongoing challenge. Substantial researches have been carried out and are underway, in order to address the diverse issues related to thermal, mechanical and structural performances of automobile disc brakes. With the extensive application of numerical tools and techniques, the analyses involved became easier and effective. The present article provides an exhaustive review of the numerical and experimental studies reported so far, on the analysis and design of solid and ventilated disc brakes. The directions for future works are also described. The review reveals that, there is enough scope for extended research for realizing optimal design of disc brake system by truly emulating all the relevant practical situations.

Thermo-Mechanical and Structural Performances of Automobile Disc Brakes: A Review of Numerical and Experimental Studies

Estimation of Dynamic Contact Force Between a Pantograph and Catenary Using the Finite Element Method

In this study, an analysis technique that can estimate the temperature rise and thermal deformation of the ventilated disc considering vehicle information, braking condition and properties of the disc and pad is developed. The analytical process of the braking power generation during braking is mathematically derived. The thermal energy that is applied to the surface of a disc as heat flux is calculated when a vehicle is decelerating from 130 km/h to 0 km/h with deceleration of 0.4 g. Then, the temperature rise and thermal deformation of a disc are calculated through the thermo-mechanical analysis by using SAMCEF code. The shape of the cross section of the disc is optimized according to the response surface analysis method in order to minimize the temperature rise and thermal deformation. As a result of optimization, it is concluded that the temperature rise and thermal deformation of the disc become minimum at the same condition. The hot judder analysis is carried out using the original and optimized disc to validate the optimization result.

Young Guk Kim

Papers

Estimation of Dynamic Contact Force Between a Pantograph and Catenary Using the Finite Element Method

A Study on Thermal Characteristic Analysis and Shape Optimization of a Ventilated Disc