新型变截面双空腔吸声结构设计探讨

为改变高速公路交通噪声的严重污染现状,设计一种新型变截面双空腔吸声结构,其是由金属吸声板、前部变截面空腔、中间吸声隔层、后部空腔、背部隔声板5大部分构成。由混响室吸声系数的测定试验可知,该吸声结构在250～1 000 Hz中低频段的吸声系数均在0.65以上,总体降噪系数均大于0.60,较传统吸声结构,其吸声降噪效果有显著提升。

Probe into Design of Novel Variable Cross-section Double Cavity Noise Absorption Structure

In order to change current situations of serious pollution of traffic noise,this paper deigns a novel variable cross-section double cavity noise absorption structure,which is composed of five parts,i.e.metal acoustic panel,front variable cross-section cavity,middle absorption insulating layer,rear cavity and back sound insulating board.Based on measurement test for acoustic absorption factors in reverberation room,all acoustic absorption factors of this noise absorption structure at medium and low frequency range of 250～1 000 Hz are over 0.65,and overall noise reduction coefficients are more than 0.60 with remarkable improvement in comparison with conventional noise absorption structure.