Research And Optimization Of Buffeting Suppression Measures For Passenger Cars

In recent years,with the increasing number of highways in China,the speed of the passenger car is becoming faster and faster invisibly.As a result of the noise generated by the traditional passenger car engine,by the mechanical parts,and by the road surface has been improved and the sudden emergence of the energy automotive industry,the impact of aerodynamic noise has emerged.And buffeting noise is one of the more popular objects of aerodynamic noise in recent years.With the continuous improvement of the airtightness of passenger cars in recent years,people often choose to open the sunroof or side window to open the air in the car after driving for a long time,which is satisfying the conditions of the buffeting noise of the passenger car.The buffeting noise of the passenger car is generating when the sunroof or the side window is opened within a certain speed range,and the pressure wave generated by the unstable shear layer at the front end of the opening shed to the rear end of the opening is transmitted to the passenger compartment.The noise generated by the gas interaction in the cabin has the characteristics of low frequency and high intensity.In such a noisy environment for a long time,the occupants in the passenger compartment may feel fatigue and irritability,which seriously affects the safety of driving and the comfort of the ride.Therefore,it is of great practical significance to take measures that can better suppress the buffeting noise generated when the sunroof and side windows of the passenger car are opened.Based on the vehicle road test of passenger car and the numerical simulation method of three-dimensional buffeting noise of passenger car,several measures for suppressing buffeting noise of passenger car are proposed and verified by simulation.At the same time,some other simulation methods of buffeting noise of passenger cars are also explored.The main research contents are as follows:1.Based on a passenger car,the vehicle road test and the simulation method of three-dimensional buffeting noise are carried out.And the results are compared,which verifies the accuracy of the simulation results.At the same time,based on the simulation method of three-dimensional buffeting noise,the mechanism of the sunroof buffeting noise is explained;2.Based on the original model of a passenger car,the simulation of the two-dimensional buffeting noise is carried out when the sunroof is opening.And the simulation results are compared with the simulation results of the three-dimensional buffeting noise to verify the feasibility of two-dimensional simulation.3.The optimal design of the spoiler at the leading edge of the sunroof is proposed and several measures of suppressing the buffeting noise of the sunroof and side windows are proposed.The mechanism of suppressing buffeting is explained by analyzing the vorticity cloud diagram at the opening.4.The porous media model is used to study the popular sunroof mesh spoiler,and the law of suppressing sunroof buffeting is found.