# Flow-Induced Vibration Analysis by Simulating a High-Speed Train Pantograph
###### 1 Introduction
[28] developed a dynamic coupling model for double-pantograph-catenary systems, validated with field tests, revealing the impact of speed, span, and wind on contact force fluctuations. [PERSON] and [PERSON] [29] created a 17-DOF model to analyze the time-varying characteristics of guide roller-rail contact stiffness in super high-speed elevators, showing significant influence on horizontal vibration. [PERSON] et al. [30] evaluated crosswind effects on pantograph-catenary interaction, finding acceptable performance at 20 m/s crosswind, but safety issues at 30 m/s, emphasizing the importance of aerodynamic forces. [PERSON] et al. [31] analyzed aerodynamic forces on HSIx pantograph components, showing the impact of configuration on drag forces and emphasizing the importance of aerodynamic modeling. [PERSON] et al. [32] developed an aerodynamic shape design method for pantograph monitoring devices, including numerical simulation and shape optimization, applicable to other small devices. [PERSON] et al. [33] explained how higher train speeds can improve pantograph-catenary performance in certain ranges, establishing a model, defining critical speeds, and proposing an indicator to predict optimal speeds. [PERSON] et al. [34] reviewed the pantograph-catenary electrical contact system in high-speed railways, discussing progress, challenges in harsh environments, and outlooks for ultra-high-speed trains. [PERSON] et al. [35] studied fluctuating loads on pantograph-catenary systems, conducting experiments to measure stability and offline rate, and using support vector machines to predict electrical contact failures. [PERSON] et al. [36] developed a spatial coupling model for pantograph-catenary dynamics under vehicle-track excitation, considering rail irregularities' impact on contact reliability. [PERSON] et al. [37] conducted an experimental study on pantograph-catenary discharge, showing that voltage, gap distance, and electrode motion affect discharge characteristics, with the vertical motion causing larger pulse current peaks and stronger radiation. In summary, as trains continue to increase in speed and as pantograph structures evolve towards lightweight designs, the impact of local deformation of pantograph components on the dynamics of the pantograph-catenary interaction becomes increasingly significant. In order to study further the coupling mechanism between the high-speed operation of the pantograph and the high-speed flow field, the equivalent mass, spring stiffness, and damping parameters in the multi-mass model are artificially assumed to be relatively large, without considering the flexible deformation of the pantograph components, resulting in low accuracy; Moreover, the multi-rigid body model and the rigid-flexible coupling model treat all or part of the pantograph structure as a rigid body, ignoring the flexible deformation of the members, resulting in significant errors under high-speed working conditions. This article adopts a new calculation method to establish a fully flexible simulation model of the pantograph coupled with high-speed flow field aerodynamic simulation results. This article studies the flow-induced vibration of pantographs under different working conditions, analyzes the effects of operating speed, knuckle-upstream and knuckle-downstream operating condition of pantographs, and structural parameters on flow-induced vibration, and proposes optimization suggestions for pantographs. Figure 1 illustrates the research scope and technical roadmap of this paper. This article is structured as follows: Section 2 introduces the aerodynamic simulation analysis and surface aerodynamic load extraction of high-speed pantographs. Section 3 briefly summarizes the modal simulation analysis of high-speed pantographs. Section 4 discusses the flow-induced vibration simulation method for high-speed pantographs.