Numerical studies on aerodynamics of high-speed railway train subjected to strong crosswind

Xu Wang,Zengshun Chen,Huaqiang Li,Yuanhao Qian,Xiao Zhou,Hailin Huang

doi:10.1177/1687814019887270

Abstract

Under the action of strong crosswind, the aerodynamic behavior of a rail vehicle at high speed will be changed significantly, which could directly affect the safe operation of the vehicle. With the help of the shape of train used in China, the aerodynamic characteristics of trains with scale of 1:1 is investigated using computational fluid dynamics numerical simulation method, which consists of the variation of aerodynamics force and moment with wind yaw angle, wind speed, train speed, and nose shape. After an initial validation against Baker’s results from wind tunnel test, the numerical model is then used to investigate the aerodynamic characteristics of the trains. The numerical results indicate that lift coefficient of the M train is slightly higher than TMC1 and TMC2 trains. Regardless of aerodynamics force coefficients, TMC1 reaches the maximum at a yaw angle of 75°. Aerodynamics force coefficient increases with both wind speed and train speed, but the change of which is not linear. Comparing aerodynamic force with different geometric dimensions of train nose, it is shown that height–width ratio is insensitive to side force and rolling moment, but sensitive to lift force from the yaw angle 0°–90°. The side force coefficient, as we most concern, is less than other results, when the length–width ratio is 1 and height–width is 0.87.

Highlights

With the increase of train speed, the interaction between train and air becomes very strong
Due to the complexity of air flow around trains, especially in high-speed motion, it is hard to obtain the analytical solution of aerodynamic characteristics which consists of wind pressure distribution on the train surface, wind field around the train, force and moment coefficients, and so on
The results show that the lift force, side force, and rolling moment increase with wind speed, and the ratio gradually increased

Summary

Introduction

With the increase of train speed, the interaction between train and air becomes very strong. Aerodynamic force generated by strong crosswind can cause derailment and overturning of trains, which would seriously affect the safety operation of high-speed trains.[1,2,3] due to the complexity of air flow around trains, especially in high-speed motion, it is hard to obtain the analytical solution of aerodynamic characteristics which consists of wind pressure distribution on the train surface, wind field around the train, force and moment coefficients, and so on. Reynolds-averaged Navier–Stokes (RANS),[20,21,22] detached eddy simulation (DES),[23] and large eddy simulation (LES)[19,24,25,26,27] have been employed to measure different parameters and investigate the flow around train subjected to side winds.[28,29]

Objectives

Findings

Conclusion