变参数分空腔单层微穿孔板低频降噪性能研究

Research on Low-Frequency Noise Reduction Performance of Single-Layer Microperforated Panel Structure with Variable Parameters and Separated Cavities

由于微穿孔板结构在低频噪声下无法实现高效宽带的吸声效果,为了提高低频吸声性能,需要优化吸声器的结构参数以达到需要的降噪水平。本研究优化和测试了变参数分空腔单层微穿孔板结构,该结构在低频的吸声系数高且吸声频带宽。首先,通过声电类比法建立变参数分空腔单层微穿孔板结构理论模型,分析吸声系数与结构参数之间的关系;其次,确定优化变量和约束条件,利用布谷鸟算法优化理论模型,得到最佳吸声系数的结构参数;最后,对微穿孔板结构的吸声系数进行有限元仿真,加工微穿孔板结构样品,在驻波管中进行了吸声性能测试。结果表明,3组结构参数分空腔单层微穿孔板结构和4组结构参数分空腔单层微穿孔板结构能够在400~2000 Hz的频率范围内保证高吸收(恒定超过80%)。

Because the microperforated panel structure cannot achieve high-bandwidth absorption under low-frequency noise,it is necessary to optimize the structural parameters of the sound absorber to achieve the required absorption level in order to improve the low-frequency sound absorption performance.In this research,the single-layer microperforated panel structure with the variable parameters and separated cavities is optimized and tested.This structure has a high sound absorption coefficient at low frequencies and a sound absorption bandwidth.Theoretical model of the single-layer microperforated panel structure with variable parameters and separated cavities is established by the acoustoelectric analogy method,and the relationship between the sound absorption coefficient and the structural parameters is analyzed.Through determining the optimization variables and constraints and using the cuckoo search algorithm to optimize the theoretical model,the optimal structural parameters are obtained to achieve the best sound absorption performance.The sound absorption coefficients of the microperforated panel structure are subjected to finite element simulation,and samples of the microperforated panel structures are processed and tested in a standing wave tube measurement.The results show that the single-layer microperforated panel structure with three or four sets of structural parameters and separated cavities can ensure high sound absorption(constantly more than 80%)in the frequency range of 400~2000 Hz.