管道空腔流激线谱噪声及主动控制实验研究

Experimental study on flow-induced line spectrum noise and active control of pipe cavity

空腔流激噪声是通风管道的一种重要噪声源,亟需得到抑制.建立了空腔流激线谱噪声测试实验系统,开展主动控制实验,分析了流激线谱噪声的产生机理和影响因素,验证了有源噪声控制技术抑制流激线谱噪声的有效性.实验表明:线谱噪声的产生与来流速度有关,线谱噪声频率随空腔深度增大而减小;主动控制系统表现出一些非线性特性,能够同时抑制基频和谐频处线谱噪声,系统存在最优参考频率和收敛因子.所得结果可为空气或水下空腔流激线谱噪声的控制提供参考.

Cavity flow-induced noise is an serious source of noise in ventilation ducts and needs to be suppressed urgently.In this paper,an experimental system for testing line spectrum noise was established,and active control experiments were carried out to analyze the generation mechanism and influencing factors of line spectrum noise,and the effectiveness of active noise control technology in suppressing line spectrum noise was verified.The experimental results show that the generation of line spectrum noise is related to the incoming flow velocity,and the frequency of line spectrum noise decreases as the cavity depth increases;the active control system exhibits some nonlinear characteristics,which can simultaneously suppress line spectrum noise at the fundamental and harmonic frequencies.The system has an optimal reference frequency and convergence factor.The results obtained can provide reference for the control of the line spectrum noise of the air or underwater cavity.