Research On Prediction Method Of Wheel/Rail Rolling Noise On Ballasted Track

With the high-speed development of railway,people’s demand for quality of life has alsogradually improved,but the railway noise problem has not gotten widespread attention,so sol-ve the noise question effectively caused by train and rail while the train is in motion is desper-ately needed.Thence,being the main source of railway noise,the study on the generation mech-anism of wheel-rail rolling noise is the work to be completed urgently in course of railway’srapid development.The wheel-rail rolling noise is mainly caused by the vibration of wheel-rail system,whichis excited by the wheel and rail surface roughness spectrum,that is why we need to know thecharacteristics of wheel and rail mobility firstly,if we want to predict rolling noise radiated bythe wheel and rail system.Establish the three-dimensional finite element model of the wheel,and then discuss spinning wheel’s vibration characteristics considering the wheel rotationeffect,in addition,analyze the effects of different train running speed on the mobility characte-ristics.In addition,the numerical result display that the result of wheel mobility getting by fin-ite element method is more accurate than using classical modal ansysis method.Similarly,esta-blish ballasted track system’s finite element model and research its vertical mobility using thefull method,then analyze its attenuation law of vibration along the length of the rail.Secondly,study wheel-rail vibration average response spectrums which are results ofwheel and rail surface irregularity excitations in the frequency domain on the base of thewheel-rail linear contact model of Remington,combined with the wheel-rail surface roughnessspectrum proposed by Sato.Finally,to predict the sound pressure level(SPL) of roadside rolling noise on the premisethat noise is free radiate while the train is passing,wheels are considered as a series of movingpoint source,and the rail is regarded as a finite length (through the observation point) linesource.The results show that wheel noise is higher in high frequency,and rail noise is higherthan wheel noise in low-mid frequency,and the wayside total rolling noise is prominent in lowfrequency.In addition,the result of rolling noise obtained by using finite element method aremore in line with the actual noise level than the result by using the classical modal ansysismethod again.Besides,the noise increase about4dB if the nuber of axles in the train increaseone times,and4.8dB of the distance far away from the track decrease10meters.