关键词: 后视镜, 镂空镜柄, 气动噪声, 风洞试验

Abstract: To better reflect the styling of the rearview mirrors, a domestic brand adopts an unconventional hollow mirror handle design in its new vehicle development. This paper studies and optimizes the aerodynamic characteristics of the rearview mirror handle by simulation and wind tunnel test to reduce the acoustic response in the vehicle’s driver’s cockpit. Our simulation reveals a serious airflow separation in the original mirror handle molding, accompanied by serious swirling vortex, which create unfavorable wind noises. To address the problem, this paper proposes two optimized schemes which effectively improve the velocity distribution gradient and airflow separation at the mirror handle. Our experimental results show the two optimized schemes substantially enhance the sound pressure level and speech clarity. The interior sound pressure level is reduced by 0.18 dBA and 0.21 dBA respectively, and both articulation indexes are improved by 1.5%. Meanwhile, the acoustic microphone array imaging is employed to accurately locate the component in which the roar occurs and the corresponding frequency band. By optimizing the surface roughness scheme, the contribution of the second optimized scheme is further increased by 0.02 dBA and 0.6%. Our research results validate the credibility of the simulation method in the project development process and provide some references for the design and optimization of the hollow mirror handles of rearview mirrors.