【作者】 朱旭铿； 周毅；

【Author】 Zhu Xukeng;Zhou Yi;Clean Energy Automotive Engineering Center,Tongji University;

【机构】 同济大学新能源汽车工程中心；

【摘要】 首先对近场声全息技术(Near-field Acoustic Holography,NAH)进行了概述,并根据其原理建立了基本数理模型,得到声场的空间变换公式;随后对某B级车的右侧面进行了稳态工况下的近场声全息试验,使用LMS Test.Lab软件的稳态声源识别模块进行声场重建,并对结果进行了验证;根据重建所得数据进行了噪声源识别,得到噪声频率分布的1/3倍频程带为中心频率63Hz(集中于前轮)、630Hz及1250Hz(分布于前后轮)处;结合参考点的噪声峰值频率,分析其低频噪声来源为发动机二阶振动,中高频噪声来源为轮胎噪声即喇叭效应与赫尔姆兹共振。更多还原

【Abstract】 Near-field acoustic holography is introduced firstly,then the basic mathematical model is established through the NAH theory,and the space transform formula for sound field is gained.With the help of Stationary Array-based Acoustic Source Identification module of LMS Test.Lab,the NAH test which is under steady conditions for the right side of a B car is designed and the result is validated.According to the noise source mapping established by test data,problem frequencies which are distributed over the 1/3 octave band by center frequency of 63 Hz,630Hz and 1250 Hz are confirmed,and the conclusion is gained that low frequency noise is caused by the second order vibration of the engine,while medium- high frequency noise by tire noise.更多还原