Research On The Influence Of Tire Ground Characteristic On Vibration Noise

Tires as the only contact part between the vehicle and the road surface,the vibration noise generated by the interaction between the tire and the road surface has a great influence on the NVH performance of the vehicle.The European Union has issued new regulations on vehicle noise,which includes new test methods and limits of automobile noise.Tire / road noise is the main source of automobile noise.Tire structure has great effect on the tire vibration noise,different structures corresponding to the different tire ground characteristics and vibration noise,because the tire vibration noise is mainly caused by the road excitation of the vibration of the tires.Therefore,it is necessary to further study the characteristics of the tire/road contact area parameters on the influence law of vibration noise of tires,it is for the tire vibration noise generation mechanism and structural optimization has important theoretical significance and engineering application value.Based on the 295/80R22.5 and 215/75R17.5 type of TBR tire as the research object,using the static ground pressure distribution test,stiffness test,modal test and Doppler laser vibrometer measuring sidewall vibration dynamic test to verify the accuracy of the finite element model the vibration noise.The results show that the static pressure distribution and three stiffness of the tire is consistent with the simulation results;under the dynamic test,the experimental and simulated value in the frequency domain of vibration velocity of sidewall have good consistency,which proves that the vibration noise can use the existing finite element model based on the numerical simulation of tire vibration noise.Using modal acoustic transfer vector technology and theory of acoustic boundary element numerical simulation analysis of the tyre vibration noise,to obtain the sound pressure directivity of different sites and the sound pressure spectrum curve.It is obtained that the sound pressure spectrum curve of tire noise is the same in different acoustic pressure field,but the pressure level is different.In the 400 Hz ~ 500 Hz frequency range,the acoustic pressure spectral curve of the tire noise has a largefluctuation,and the peak of sound pressure is apparent at 440 Hz and 488 Hz.The sound pressure level at the back of the tire ground is greater than the sound pressure level at the ground front.The effects of the tire ground pressure distribution geometrical and mechanical parameters on the vibration noise are studied.In order to eliminate the structural change caused by the inherent characteristics of the tire caused by the noise changes,the structural design of the modal analysis,selecting the natural frequency of the smaller changes in the structural design.Calculating alternative actual value of the vibration noise and ground pressure geometric parameters and mechanical characteristics,summarized the influence law.The orthogonal test was used to obtain the minimum noise tire structure design,analysis of the tire and the original structure design tire tread radial deformation of skewness and stiffness,excitation power spectral density tire/road ground area physical quantities on the influence law of vibration noise.The results show that the vibration noise and tread radial deformation of skewness values were positively correlated relationship,negatively related with tread deformation stiffness;the structure optimized tire size and quantity of peak exciting force power density significantly reduced,especially in the sensitive frequency of 440 Hz and 488 Hz reduced obviously.Finally,the universality of the characteristic parameters are verified.