高速铁路声屏障宽频穿孔吸声降噪结构

Multi-Layer Micro-Perforated Panels with Broadband Absorption for Reduction of High-Speed Railway Noise

摘要:

采用传递矩阵法对高铁声屏障的多层微穿孔结构的吸声进行计算。对给定空腔深度，适当增加具有不同声阻抗的微穿孔板可改善吸声性能。经遗传算法得到具有优化参数的4层和5层微穿孔结构可显著拓宽吸声频带，提高整个频带的吸声系数，在200~3 150 Hz频率范围内的平均吸声系数分别为0.70和0.80，吸声频带涵盖250~350 km?h^-1高速铁路主要噪声频率范围。5层结构在400~4 000 Hz频率范围内吸声系数可达0.8。

Abstract:

Based on the transfer matrix method， the calculation of absorption of multi-layer micro-perforated panels（MPP） is conducted. Properly increasing the number of layers with different impedance in given cavity depths can improve sound absorption performance. The 4-layer and 5-layer micro-perforated panels with optimized parameters obtained by genetic algorithm can significantly broaden the sound absorption frequency bandwidth and improve the absorption coefficient of the whole frequency range， with an average absorption of 0.7 and 0.8 respectively in the range of 200–3 150 Hz which covers the main noise frequency range of high-speed train at 250–350 km?h^-1 . For 5-layer absorbers， absorption coefficients can be higher than 0.8 at 400–4 000 Hz.