自适应消声系统的设计与性能研究

Research on design and performance of adaptive muffler system

为了有效控制低频宽带噪声,结构简单的声衬被广泛应用。传统声衬只能消除固定频率的噪声,即当环境噪声频率发生改变时,传统声衬消声性能明显下降。为此,提出了一种自适应消声系统,利用压电声衬工作原理,通过LabVIEW串口通信技术传输与控制数据程序,驱动压电声衬使它能根据噪声频率的变化自适应控制信号;通过调节电源输出电压,改变压电声衬共振腔体积,从而及时有效地调节压电声衬消声频率,拓宽压电声衬的消声频带。分析结果表明,压电声衬共振腔体积减小时,消声频带向低频方向偏移,反之向高频方向偏移;当输出电压为-100~200 V时,自适应消声系统可在噪声频率为1 364~1 420 Hz的环境中一直保持最佳的消声效果,实现了自适应消噪。研究结果表明,对声衬施加直流电源可以对其消声频率进行调节,使其消声频带随着噪声频率的变化而偏移,拓宽其消声频带。设计的消声系统可以实现噪声的自适应控制,可为声衬的主动控制及优化提供参考。

In order to effectively control low-frequency broadband noise, the sound lining is widely used due to its simple structure. However, the traditional sound lining can only eliminate the noise of a fixed frequency, that is, when the frequency of the environmental noise changes, the muffling performance is significantly reduced. To this end, this paper proposed an adaptive muffler system, which used the principle of piezoelectric sound lining to transmit and control data programs through LabVIEW serial communication technology, and drove the piezoelectric sound lining to adaptively control according to the variation of different noise frequencies. The signal, by adjusting the output voltage of the power supply, changed the volume of the piezoelectric sound lining resonant cavity, thereby timely and effectively adjusting muffling frequency of the piezoelectric sound lining, and broadening the noise anechoic band of the sound lining. The research showed that when the volume of the piezoelectric sound lining resonant cavity was reduced, the muffling frequency band was shifted to the low frequency direction, and vice versa. The output voltage was-100-200 V, and the system could always achieve the best muffling effect in the environment where the main noise frequency was 1364-1420 Hz, and achieved adaptive noise elimination. Therefore, applying a direct-current power supply to the sound lining could adjust the muffling frequency, so that the muffling frequency band of the sound lining shifted with the change of the noise frequency, widening the muffling frequency range of the sound lining. The designed muffler system can realize the adaptive control of noise, and provide a reference for the active control and optimization of sound liner.