摘要
设计了具有小尺寸的中低频宽带旁支管消声器。首先,应用传递矩阵法,建立了单旁支管消声器的声波传递损失数学模型;然后,以预设的共振频率为目标,计算单旁支管消声器的结构参数,并在分析结构参数对传递损失影响的基础上,择优建立旁支管消声单元;接着,将消声单元进行轴向和周向阵列,形成周期结构,研究周期性对消声性能的影响;最后,通过周期阵列具有不同共振频率的消声单元,设计了有效消声频带为493~3 033 Hz的消声结构,同时借助旁支管侧支的弯曲,实现了结构的小尺寸设计。研究结果表明,轴向分支周期数不影响共振频率,但随着周向分支周期数的增加,结构共振频率会向高频滑动,且滑动幅度会逐渐减缓;轴向分支周期数和周向分支周期数的增加,都能显著提高旁支管消声器的有效消声带宽;通过采取侧支弯曲的设计,能减小消声器的结构尺寸,且对消声性能影响不大;综合利用轴向周期和周向分支周期阵列,以及采用组合具有不同共振频率旁支管单元的方法,能获得性能优异的中低频宽带消声器。
A mid-and low-frequency broadband side branch pipe muffler with small size is designed.At first,a mathematical model is established to describe acoustic transmission losses of a side branch pipe muffler by using the transfer matrix method,and the side branch pipe mufflers with preset resonance frequencies are designed;then the influences of structural parameters of the mufflers on transmission loss are analyzed,and a side branch pipe unit is subsequently determined based on the analyses.Next,periodic structures are formed by arraying the units along the axial or circumferential directions of the main propagation path of acoustic wave,and the influence of periodicity on noise reduction is studied.Finally,side branch pipe units with different resonant frequencies are combined to build a periodic structure with an effective bandwidth of 493-3033 Hz,meanwhile,side branch pipes are bended to reduce structural sizes.The results show that,the number of axial branching period does not affect the resonant frequency of the structure,but,with the increase of the number of circumferential branching period,the resonant frequency will shift to high frequencies,and the shift amplitude will gradually slow down;the increase of the numbers of axial branching and circumferential branching periods can significantly extend the effective bandwidth;bending side branch pipes can reduce structural sizes and has little influence on structural acoustic characteristics;a mid-and low-frequency broadband muffler can be obtained by the integrated utilization of the structures with different axial branching and circumferential branching periods,as well as by combining the side branch pipe units with different resonance frequencies.
作者
王超
梅玉林
王晓明
WANG Chao;MEI Yulin;WANG Xiaoming(School of Automotive Engineering,Dalian University of Technology,Dalian 116024,Liaoning,China;School of Mechanical Engineering,Dalian University of Technology,Dalian 116024,Liaoning,China)
出处
《声学技术》
CSCD
北大核心
2024年第6期876-886,共11页
Technical Acoustics
基金
国家自然科学基金(51975083、51775080)。
关键词
旁支管消声器
传递损失
共振频率
中低频
宽带
side branch pipe muffler
transmission loss
resonance frequency
middle and low frequency
broadband
