Suppression of the flexible carbody resonance due to bogie instability by using a DVA suspended on the bogie frame
Caihong Huang, Jing Zeng
Abstract
A novel method is proposed to suppress the flexible carbody resonance due to bogie instability by hanging a dynamic vibration absorber (DVA) to the bogie frame. The aim is to design the DVA to change the frequency of the bogie hunting motions, which can ensure the bogie does not operate at the resonant frequency of the objective mode of the flexible carbody. Firstly, the resonance phenomenon of the flexible carbody is introduced. The reason is revealed that the unstable frequency of the bogie hunting motions matches the resonance frequency of the carbody diamond mode, which is identified experimentally by modal testing. Then the unstable behaviour of the bogie with a suspended DVA is studied theoretically by building a simple lateral dynamics model of a bogie system. The basic mechanism of the effect of a DVA on the hunting frequency jump characteristic is explored. It is then adopted to suppress the carbody resonance due to bogie instability in the rigid-flexible multi-body dynamics model of a high-speed railway vehicle. The optimum parameters of the DVA suspension are determined numerically by deigning the unstable frequencies away from the objective natural frequency of the flexible carbody, and its effect on resonance suppression is confirmed.