双开口Helmholtz局域共振周期结构低频带隙特性研究

发布时间：2018-03-14 18:42

本文选题：Helmholtz共振　切入点：周期结构　出处：《物理学报》2017年06期 　论文类型：期刊论文

【摘要】：设计了一种双开口Helmholtz周期结构,该周期结构单元采用双开口内外腔设计,基于多腔耦合局域共振机理,可大大增加局域共振区域,增加能得到较低的低频带隙特性.通过设计调节内腔弧长,可以使带隙移动,达到特定低频频段的隔声效果.在分析低频带隙形成机理和影响因素时,采用声电类比原理建立带隙起始频率和截止频率的计算数学模型并与有限元方法进行对比分析.研究表明:该结构具有良好的低频带隙特性,其最低带隙段为86.9—138.2 Hz.外径一定的条件下,低频带隙受内腔弧长、内外腔间隔以及周期单元结构间隔影响,内腔弧长越长,低频带隙越低;内外腔间距离越大,从而内腔体积变小,带隙向高频移动,其低频效果变差;减小结构间距对低频带隙起始频率无影响,但可以大大增加低频带隙截止频率,从而增加带隙宽度.该研究结论可以为低频降噪领域提供一定的实践和理论支持.
[Abstract]:Design of a double opening Helmholtz periodic structure, the periodic structure unit with double opening design inside and outside the cavity, multi cavity coupling mechanism based on local resonance, can greatly increase the local resonance region, have a low frequency low band gap characteristics can be increased. Through the design and adjustment of inner arc length, can make the band gap move, reach a certain low frequency band the sound insulation effect. In the analysis of low frequency band gap formation mechanism and influencing factors, using the acoustic electric analogy principle to establish the mathematical model for the calculation of band gap of the initial frequency and cut-off frequency are compared and analyzed with the finite element method. The results show that the structure has good low-frequency band gap characteristics, the lowest band gap is 86.9 - 138.2 the outer diameter of Hz. under certain conditions, the low frequency band gap by an arc length, and cavity interval and periodic unit interval structure, inner arc length is longer, the low frequency band gap is low; the greater the distance between the inside and outside the cavity, thereby The cavity volume becomes smaller, the band gap moves to high frequency, the low frequency variation effect; reduce the structural spacing had no effect on the low frequency band gap starting frequency, but can greatly increase the low-frequency band gap cutoff frequency, thereby increasing the width of the band gap. The conclusion of the study can provide some practical and theoretical support for the low frequency noise in the field.

【作者单位】：空军工程大学航空航天工程学院;空军工程大学理学院;西安飞行学院;
【基金】：国家自然科学基金(批准号:11504429)资助的课题~~
【分类号】：O735

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