Analysis on Geometric Filtering Phenomenon and Flexible Car Body Resonant Vibration of Railway Vehicles

Abstract:

The geometry filter phenomenon is analyzed with a simplified vertical railway vehicle.Then the relationship between geometry filter phenomenon and the resonant vibration of flexible carbody is studied with a full vehicle model.It is found that geometry filter phenomenon consists of “wheelbase filter” effects and “bogie center filter” effects.It is called wheelbase filter effect when there is neither car body bounce nor pitch responses at some wavelengths.And it is called bogie center filter effects when there is no car body bounce or pitch response at some track wavelengths.Near the null pitch response frequencies,the acceleration transmissibility from track unevenness to carbody bounce will reach local maximum.So if the carbody first bending frequency coincides with the frequencies which have the peak values of acceleration transmissibility,resonant vibration of flexible carbody will happen.

Key words:railway vehicle; geometry filter; carbody flexibility; ride quality