某SUV车内气动噪声特性风洞试验研究

A Study on Wind Tunnel Test of Interior Aerodynamic Noise Characteristics of a SUV

为研究乘用车内部气动噪声的空间分布规律、频率特性和车内噪声水平的影响因素,以便进行改进设计,对某款SUV在吉林大学汽车风洞内进行了噪声测试试验。结果表明,车内气动噪声主要由泄漏噪声与外形噪声组成,空间上车内噪声左右对称分布,但发现了前排泄漏噪声高于后排、而后排外形噪声高于前排这一典型现象。车内噪声水平随风速增加呈线性递增,且随着偏航角度增加,处于背风侧的位置,由于气流分离变甚,噪声明显恶化,而迎风侧的噪声变化很小。根据试验结果提出对A柱附近的衬条进行局部补强,采用泡棉封堵后视镜与车身连接处线束穿孔,采用喇叭口造型和减薄镜柄的新造型后视镜,以及在顶棚和四门钣金件加贴阻尼片等一系列车内噪声改进方案,有效降低了车内气动噪声。

In order to study the spatial distribution pattern, fi＇equeney characteristics and influencing factors of interior aerodynamic noise of a passenger ear for modifying design and lowering noise, a noise test is conducted on a SUV in the wind tunnel of Jilin University. The results show that aerodynamic noise is mainly composed of leakage noise and shape noise, and exhibits spatially symmetric distribution between left and right, but a typical phenomenon is found that the leakage noise at front row is higher than that at rear row, while the shape noise at rear row is higher than that at front row. The sound pressure level of interior noise increases linearly with the increase of wind speed and also goes up with the rise of yaw angle. In the locality on the leeside, the noise obviously deteriorates due to airflow separation becoming severer, while the noise on windward side has just little changes. According to test resuits, a series of modification schemes for reducing interior noise are adopted, including locally upsizing the sealing belt near A-pillar, plugging the harness hole for rearview mirror with sound insulation foam, using a new-style rear- view mirror with a flared shape and a thinner bracket, and pasting damping pieces on door and roof panels. As a resuit, the interior aerodynamic noise of vehicle is effectively attenuated.