The dynamic characteristics of the hydraulic damper on the high-frequency vibration transmission of the bogie

The dynamic characteristics of the damper, affected by the mode of compression deformation and the oil flow rate, has an influence on vibration transmission, and on structure-borne sound transmission. The vibration transmissibility of the damper will be smaller when the input force is big, which leads to a change in structure-borne sound transmission. To analyse the dynamic characteristics of the hydraulic damper, and its effect on structure-borne sound transmission to the bogie, a simplified structure-borne sound damper model is established. This is done by taking the vertical damper as an example, and using parameters obtained by FRF (frequency response function) tests and quasi-static tests. By introducing the damper model into the vehicle-track coupled dynamic model, the contribution of different components of the primary suspension to structure-borne sound transmission is simulated. The results show that the damper’s contribution is relatively large for frequencies between 32.5 Hz and 43.5 Hz, and at 650 Hz, 820 Hz and 870 Hz, while the damper’s contribution is nearly 0, between 410 Hz and 580 Hz. With the increase of wheel wear, the vibration transmission rate of the damper decreases gradually, and the damper’s contribution is increased by between 0.01 (1%) and 0.1 (10%), between 32.5 Hz and 259 Hz.