摘要
提出了一种新型的宽频带共振吸声结构,该结构基于赫姆霍兹共振吸声机理,并充分利用了软管在长度上的优势,易于实现对低频噪声的控制。论文通过分域处理并建立不同区域声学边界条件的方法,考虑了软管的管壁特性,从理论上给出了这种结构的吸声特性。实验证明本文提出的新型宽带共振吸声机理正确,利用本文提供的分析方法可以精确计算系列共振频率及其吸声系数,利用本文提出的增加软管长度和系列软管组合的方法可有效拓宽吸声频带。这种新型吸声结构的提出,为低频宽带噪声控制提供了新的途径,为对次声和极低频噪声的防护提供了技术基础。
A new structure for the broadband sound absorption is proposed in this paper. Based on the sound absorption mechanism of Helmholtz Resonator, the advantage of soft tube length is fully used in the new structure, and thus the low-- frequency noise can be controled easily. The acoustic boundary conditions in different areas are set up based on a consideration of the wall characteristics of soft tubes, and then the theoretic sound absorption characteristics of this new structure are given. The proposed mechanism for the new broadband resonance structure is confirmed by experiments. By using the analytic method proposed, the resonance frequency and the sound absorption coefficient are accurately calculated. Via increasing the soft tube length and combining a series of soft tubes, the frequency band of sound absorption is effectively widen. A new approach to reduce low-frequency and broadband noise is provided by using this structure, which lays a technical foundation for infrasound and very low-frequency noise control.
出处
《振动工程学报》
EI
CSCD
北大核心
2007年第2期145-148,共4页
Journal of Vibration Engineering
基金
教育部新世纪人才计划(NCET-04-0959)
国家自然科学基金资助项目
关键词
宽带
共振
吸声
赫姆霍兹
broadband
resonance
sound absorption
Helmholtz
