两种识别复杂噪声源的多输入频域模型

本文按多输入/单输出(MISO)频域模型对一台疲劳试验机工作状态下的噪声进行了测量与计算,获得了各部件振动辐射噪声的动态特性和有关数据,同时论述了用多输入/二输出(MITO)频域模型对双麦克风声强法的改进,以解决在机器中同时存在的非结构振动噪声源(如空气动力噪声、电磁噪声)以及互相耦合的多个声源的定量识别问题。

Two Multiple-Input Frequency Domain Models for Noise Source Identification

This paper deals with the procedure of application of the multiple-input frequency domain models in identifying the noise source in a complex structure. The structure is modelled as a multiple-input with a single or a two output one, where the signals from the accelerometer gives the sound radiation characteristics of each member are the inputs and the sound pressure signals from the microphones are the outputs. The corresponding frequency response function for each of the input and output signals can be found through a least square approximation. The contributions associated with each individual source to the measured sound pressure or intensity can then be estimated. To demonstrate the practical implementation of the method, an analysis was performed with success on a fatigue testing machine with type HP5423A Dynamic Structural Analyzer and a type HP1000 computer. The identification of the aerodynamic noise source in the machine is discussed.