Influence Analysis On Structural Parameters Of High-Speed Train Wheelset Based On Its Dynamic Characteristics

In the running process of high speed train, the wheel-set bears the vibration caused by the wheel-rail force. The vibration characteristics of the wheel-set are the foundation of the first suspension parameter matching and wheel-set parts fatigue analysis, also has an important influence on security and stability of the train. According to the study of the dynamic characteristics of the wheel, the vehicle multi-body dynamics analysis method is unable to guide wheel structure design, due to too much abstract of the wheel-set, meanwhile, accuracy problems in the current wheel-set dynamics modeling lead to some simulation errors. To solve these problems, it is essential to establish a complete wheel-set structure dynamics analysis model. Based on the model, the influence of structure parameters on the wheel-set dynamic characteristics are studied systematically to provide efficient advice to designers.Through a detailed analysis of the wheel-set actual constraints state, in the light of vehicle multi-body dynamics modeling method and wheel dynamics modeling method, finite element model and physical model of wheel-set structure dynamics are established. By analyzing three different vibration forms of wheel-set, three mathematical models (pendulum angle vibration model, bending beam model and horizontal swing model) are bulit, the effects of wheel structure parameters (wheel radius, the position of the gear box, the length of the rotating arm) on the main vibration frequency are analyzed qualitatively. To get the exact solution, by means of finite element method, constrained modal analysis, harmonic response analysis and transient dynamic analysis, the influence of the structural parameters on the vertical vibration modal frequency, vibration mode, and vertical acceleration amplitude frequency characteristics are analyzed systematically; then, the advice of wheel structure design is developed. The main research results of this paper are as follows.(1) To solve the problem of the existing vehicle multi-body dynamics analysis is unable to establish the relationship between structure parameters and performance parameters, wheel-set structure dynamic complete analysis model is established, which includes detailed structure parameters and complete constraints.(2) The existing wheel-set modal analysis technologies focused on free modal analysis, lacked systematic study on the actual constrained modal analysis. Through comparison the results of free modal analysis and constraint modal analysis, it turns out that the latter is more useful. the anfluence of the structural parameters (wheel radius, the position of the gear box, the length of the rotating arm)on front six constraint modes and frequencies It is further explored to instruct wheel-set structure design from the view of changing main vibration frequency and modes maximum deformation.(3) The actual wheel rail force contains a variety of periodic components load, according to the principle that any cycle load can be fitted by harmonic, trough the harmonic response analysis of wheel component, the wheel-set vibration modes superposition results under the periodic component of wheel-rail force are determined, the frequency ranges which may cause wheel-set vertical vibration resonance are recognized.(4) By the transient structural dynamics analysis of wheel-set, the dynamic stress concentration condition under actual load is identified.the whole structure dynamic analysis process from the modal analysis, harmonic response analysis to the transient dynamics analysis arediscussed systemically.