The coupled effects of bending and torsional flexural modes of a high-speed train car body on its vertical ride quality

Abstract

This study is focused on the effects of bending and torsional flexural modes of the car body on the ride quality index of a high-speed train vehicle. The Euler–Bernoulli beam model is used to extract an analytical model for a high-speed train vehicle car body in order to investigate its bending and torsional flexural vibrations. The rigid model includes a car body, two bogie frames, and four wheelsets such that, each mass has three degrees of freedom including vertical displacement, pitch motion, and roll motion. The results obtained with the proposed analytical model are compared with experimental measurements of the car body response of a Shinkansen high-speed train. Moreover, it is determined that the bending and torsional flexural modes have significant effects on the vertical acceleration of the car body, particularly in the 9–15 Hz frequency range. Furthermore, the ride quality index is calculated according to the EN 12299 standard and it is shown that the faster the train the more affected is the ride quality by the flexural modes. In addition, the effect of coherence between two rail irregularities (the right and the left rails) on the results of the simulation is investigated. The results conclude that if the irregularities are completely correlated the torsional flexural mode of the car body does not appear in the response. Also, the first bending flexural mode in such cases is more excited compared with the partially correlated or uncorrelated rail irregularities. Therefore, the ride quality index in completely correlated cases is higher than other cases.

A numerical and scaled experimental study on ride comfort enhancement of a high-speed rail vehicle through optimizing traction rod stiffness

“…At about 20 Hz, a peak in the acceleration of the carbody floor is observed, which is related to the longitudinal stiffness of the traction rod. Without the presence of the traction rod, such a peak does not appear at all (Bokaeian et al, 2019). This peak is an indicator of the existence of the bogiecarbody dynamic interaction.…”

“…The presence of some anti-peaks within the results for the vertical acceleration of the carbody is clear. These anti-peaks represent a phenomenon known as the bogie-base filtering effect (Bokaeian et al, 2019;Gong et al, 2012;Tomioka and Takigami, 2010). The agreement between the two sets of the results for the frequency range of 3 to 20 Hz is about 20%.…”

“…The ride quality index in the carbody walls worsens when compared with the centerline of the carbody. When moving away from the centerline of the carbody in the transversal direction, the acceleration associated with the roll of the carbody also affects its vertical acceleration (Bokaeian et al, 2019).…”

“…Several studies have focused on the effect of the carbody's flexural modes on the ride quality index of railway vehicles. Carlbom (2000), Zhou et al (2009), Younesian et al (2014), Shi and Wu (2016), Ling et al (2018), Akiyama et al (2019), and Bokaeian et al (2019) studied the effect of flexural modes of the carbody on passengers' ride comfort. Those researches demonstrated the significant influence of the first bending mode of the carbody on its ride quality.…”

Dynamic Analysis of a High-Speed Railway Train With the Defective Axle Bearing

“…Cantero and Karoumi 14 analyzed the effects of the train speed, track irregularity cases, and bridge characteristics on the vibrations from a train-trackbridge system. Bokaeian et al 15 used a Euler-Bernoulli beam model to study the torsional and bending vibrations of the HST body. Although some works considered the train vibrations including the axle bearings, they did not consider the local faults in the AXBs.…”