Study On Tire Acoustic Modal Test And Influence Range Of Different Noise Sources On Low Frequence Band

It has always been a research hotspot to study the vibration and noise characteristics of tires and improve the NVH performance of tires.When the tire speed reaches a certain value,the sound pressure level in the car is high,the buzz is obvious,and the subjective evaluation is unacceptable.It is necessary to establish a standard for the influence range of different noise sources on the frequency band,so as to quickly locate the problem points and solve the problem of excessive tire noise.You can conduct noise test on the tire first,find out the frequency band of excessive noise,and then quickly find out the reason according to the classification standard.It is concluded that the tire modal,tire pattern and tire cavity are the main factors that affect the tire noise.In order to get the dividing standard of frequency band,it is necessary to get the tire modal,tire pattern and tire cavity,according to a large number of tire tests and theoretical formula calculation,to get their influence on the frequency band range.First study of tire modal,develop a new type of tire modal vibration signal acquisition method,the acoustic modal test,through the finite element modal analysis results of acoustic modal test results were analyzed to verify the feasibility of acoustic vibration modal method,the acoustic vibration modal test and the traditional modal test for the same tire modal acquisition,by comparison with the results verify the accuracy of acoustic vibration modal,The influence range of the mode on the low frequency band is obtained.In the study of tire pattern,several tires were selected for testing,mainly to study the influence range of different specifications with different patterns and the same specifications with different patterns on frequency band;In the study of tire cavity,theoretical formula is used to directly calculate the cavity frequency of different tires,and finally the influence range of different noise sources on the low frequency band is obtained.In the modal research,it is found that the frequencies of 0-200 Hz are mainly affected by the modes.The acoustic and vibration modal testing method can identify the double root mode and cavity mode more easily.In the study of tire cavity,it is concluded that the cavity mainly affects the frequency band of 200-250 Hz.In the study of tire pattern,it is found that the pattern mainly affects the frequency band of 300-800 Hz.The noise value of multi-pitch pattern arrangement is lower than that of single pitch,and the noise value of asymmetrical pattern tire is lower than that of symmetrical pattern.In this paper,a new modal signal acquisition method has been developed,and the influence range of different noise sources on the frequency band has been obtained,which successfully solves the problem of excessive tire noise.It has certain guiding significance for tire optimization design and tire industry development in the future.