Study On The Influence Of Road Excitation Transmission Path On Interior Noise And Its Optimization

The performance of automobile NVH(Noise,Vibration and Harshness)is an important index in the development of passenger vehicle.According to the current situation of domestic vehicles,passenger cars are mainly driven by medium speed.The excitation from the uneven pavement is transmitted to the body by suspension system,which causes the vibration and noise of the body to become the main factor affecting the ride comfort.Therefore,the research on the influence of pavement excitation on the noise of the car has a great theoretical significance and high practical value.At present,there is no complete technical system to solve the problem of pavement noise,and the problem of pavement noise is more unpredictability.In this study,an SUV model was used to study the effects of road excitation transmission path on the noise of the vehicle.The research contents are as follows:Based on the mechanism of pavement noise,this paper puts forward the pavement noise performance is mainly for the car in low frequency noise,TPA to Transfer Path Analysis(Transfer Path Analysis)theory as the basis,establish the wheel heart to the vehicle response(MTPA of driver's right ear location),multiple reference Transfer Path)model;Using LMS test.The Lab of Transfer Path Analysis test system for the SUV models the TPA test,through the inverse matrix method of the wheel load force identification,and the uniform conditions predict main road excitation noise peak,development to provide important reference for vehicle suspension frequency;The acoustic pressure in the vehicle is compared with the measured sound pressure,the load value and the excitation peak value are verified.By comparing the modal simulation and test results of the decoration body,the correctness of the model is verified,and the modal analysis of the sound field in the car is obtained,and the front row pressure is large and the focus needs to be adjusted.Based on wheel heart load force spectrum identification,combining spoke model with the finite element model for vehicle constitutes a solid coupling model,as an acoustic excitation input to the vehicle fluid-solid coupling finite element model of acoustic sensitivity analysis,verified the former the TPA incentive main value;Based on the analysis of the transmission path contribution of the target point peak of the vehicle,the noise control strategy of the vehicle was proposed based on the modal participation factor.Compared with the original state through CAE method,the effectiveness of the scheme was verified,and the peak sound pressure value of the noise in the car was reduced by about 5dB,so that the noise value in the car reached the standard,the TPA test is combined with the sound pressure simulation to achieve the feasibility of prediction analysis.