基于频谱分析的挖掘机噪声特性研究

本文通过采集挖掘机柴油机排气噪声、消声器排气噪声、柴油机壳体辐射噪声和操作室内噪声的声压信号，分析了空载条件下噪声声压信号的频谱特性，给出了各噪声信号在不同柴油机转速下的A声级噪声值。得出结论：柴油机排出噪声覆盖高、中、低频段；各噪声频谱特征比较类似；共振导致怠速时的柴油机振动比较大；各噪声强度均随柴油机转速的提高而增大；噪声源以及消声器排出噪声的低频段声压比较大的频率均是柴油机转速基频的倍数。

Noise Character Study of Excavator Based on Spectrum Analysis

The spectrums of noise discharged out of excavator diesel, noise exhausted through resistance muffler, noise well radiation of the diesel and the noise in manipulator cell has been analyzed with the corresponding noise signal collected, and the A sound pressure levels have been measured with different diesel rotation respectively. Conclusions have been obtained as following: the noise signal discharged out of excavator diesel covers high, middle and low band widely; all the kinds noise signal have similar spectrum with different amplitude; the vibration is much bigger at idle speed is than the others; the noise strength increases with the diesel rotation rising. Low band frequencies with big spectrum amplitude of noise resource and the other noise signal collected are multiples of diesel rotation.