Study on Geometry Filtering Phenomenon and Flexible Car Body Resonant Vibration of Articulated Trains

A vertical rigid-flexible coupling dynamic model of three articulated vehicles with car body flexibility is established, Green functions are utilized to solve the partial differential equation of each car body, and the mechanism of car body flexible resonance is analyzed. Results show that geometry filtering phenomenon exists in articulated train, when the car body first vertical bending frequency coincides with the frequencies which have the peak values of car body bounce acceleration transmissibility, resonant vibration of flexible car body will happen; The energy of track irregularity decreases rapidly with the increasing frequency, so it is important to avoid the car body resonance at low frequency; If the first vertical bending frequency of car body is greater than a certain value, the flexible resonance will have little effect on the ride quality.