Study On Aerodynamic Noise Control Of The SUV A-pillar

The aerodynamic noise generated during high-speed driving of the car has a great influence on the comfort of the car.Therefore,reducing the aerodynamic noise plays an important role in improving the comfort of the passengers.The A-pillar-and front windshield,A-pillar-and rear-view mirrors,and A-pillar-side window areas are the main aerodynamic noise source areas that affect the comfort of the car.A combination of experimental and simulation methods is used to generate aerodynamic noise.The mechanism and laws of the study.The Realizable K-? turbulence model was used to study the design parameters of the size difference between the A-pillar and the front windshield of an SUV,the position of the A-column ridgeline and the ridgeline curvature radius of the A-pillar.The main results are as follows:(1)The difference between the design parameters of the A-pillar and the front windshield has an important influence on the surface pressure and the turbulent energy of the front windshield,the side window and the rearview mirror area.As the size difference between the A-pillar and the front windshield increases,The less the flow field in the area is,the easier it is to improve.(2)The design parameters of the A-pillar ridge line have a great influence on the surface pressure and turbulent kinetic energy of the front windshield,side window and rearview mirror area,and the surface pressure pulsation and turbulent kinetic energy of the third working condition are small.(3)The design parameters of the radius of curvature of the A-pillar have a great influence on the pressure pulsation and turbulent kinetic energy of the rear view mirror and the side window region.The larger the radius of curvature,the better the flow field improvement in the region.The LES turbulence model is used to calculate the transient flow field of the A-pillar region of a SUV.The results of the simulation calculation are compared with those obtained by the wind tunnel experiment,and the correctness of the simulation calculation method is verified.Using this method combined with the Curle surface sound source model and the Proundman bulk sound source model to simulate the aerodynamic noise source in the A-pillar region,the results are as follows:(1)The size difference between the A-pillar and the front windshield design parameters has an important influence on the surface sound source of the A-pillar windward surface and the body sound source of the side window area.The difference between the A-pillar and the front windshield section is reduced,and the surface of the A-pillar windward side is reduced.The sound source of the sound source and side window areas is improved,and the sound pressure level of the monitoring points on the side windows gradually decreases with the step.(2)The design parameters of the A-pillar ridge line have a great influence on the A-pillar wind surface sound source and the side window mirror area sound source.Changing the ridge line position can significantly improve the aerodynamic noise near the A-pillar.The most significant improvement is obtained for the A-cylinder sound source and the body sound source in the side window area.(3)The design parameters of the curvature radius of the A-pillar have a significant influence on the sound source of the A-pillar windward surface and the body sound source of the side window area.The radius of curvature of the A-pillar ridge line is larger in the working condition range,for the A-pillar area.The improvement in aerodynamic noise is more obvious.