Abstract:
When the external excitation frequency approaches the natural frequency of the system, resonance occurs, significantly affecting vehicle operational safety and causing structural fatigue in key components. To address this, an in-depth analysis of the relationship between these frequencies and their influence on vehicle system vibrations is required. This study constructs a dynamic model of the vehicle system, including the car body, bogie frame, and wheelset, and obtains the system’s natural frequencies and primary mode shapes using the complex modal analysis method. Harmonic excitations with different wavelengths are designed as input disturbances for the model, and numerical methods are employed to calculate the system’s vibration response under various parameter conditions. The variation patterns of resonance peaks and frequency ratios under different damping and stiffness parameters are explored. The reasons for peak vibration acceleration when the excitation frequency exceeds the natural frequency are also explained. Results show that when the primary and secondary damping increase from 60 kN
.s
.m
−1 to 100 kN
.s
.m
−1, the vibration amplitude decreases by 39%, and the resonance bandwidth expands from 2.42 Hz to 5.69 Hz. The resonance frequency ratio of bogie frame acceleration increases from 1.04 to 1.13 with increasing damping and decreases from 1.13 to 1.06 with increasing stiffness. It is recommended that the frequency ratio be maintained below 0.87 or above 1.42 to suppress bogie frame resonance. The ratio of mode shape magnitudes between components can be used to evaluate changes in relative vibration peaks under different system parameters. These findings provide significant insights for the design of high-speed train suspension parameters and the development of structural resonance suppression methods.