基于声学虹吸效应的水下低频大宽带吸声机理研究  

A study on the mechanism of underwater low frequency and wide band sound absorption based on acoustic siphon effect

作　　者：马承志 王立博 吴晓 吴九汇[1,2] MA Chengzhi;WANG Libo;WU Xiao;WU Jiuhui(School of Mechanical Engineering,Xi’an Jiaotong University,Xi'an 710049,China;State Key Laboratory for Strength and Vibration of Mechanical Structures,Xi’an Jiaotong University,Xi'an 710049,China)

机构地区：[1]西安交通大学机械工程学院,西安710049 [2]西安交通大学机械结构强度与振动国家重点实验室,西安710049

出　　处：《振动与冲击》2022年第16期100-107,187,共9页Journal of Vibration and Shock

基　　金：国家自然科学基金(51675401)。

摘　　要：利用有限元软件COMSOL建立了薄板型超材料的仿真模型,在声学虹吸效应基础上研究了其低频大宽带吸声机理。通过探究在声学虹吸效应作用下压差声汇机理、声阻抗匹配机理及负动态等效密度机理,验证了该超材料的低频大宽带吸声性能;讨论了面积比、薄板厚度和质量块高度等参数变化对于薄板型超材料的吸声性能影响。结果表明:当一定频率的平面波入射该超材料时,会在元胞某一位置处发生共振,具有最大的吸声量,在不同面积比的情况下,该超材料仍然具有较为匹配的声阻抗,几乎所有入射能量可以被迫流向这种谐振元胞,增强元胞振动,使之仍然保持良好的吸声效果;当薄板厚度变小或者质量块高度变大时,吸声系数的峰值频率会向低频移动。最后,通过合理设计优化薄板型超材料的各项参数实现了水下100-500 Hz的低频大宽带吸声。A simulation model of thin plate metamaterial was established by using finite element software COMSOL,and its low frequency and wide band sound absorption mechanism was studied on the basis of acoustic siphon effect.By exploring the mechanism of differential pressure acoustic convergence,acoustic impedance matching and negative dynamic equivalent density under the action of acoustic siphon effect,the low frequency and wide band sound absorption performance of the metamaterial was verified.The effects of parameters such as area ratio,sheet thickness,and mass height on the sound absorption properties of thin plate metamaterials were discussed.Results show that when a plane wave of a certain frequency is incident on the metamaterial,the resonance will occur at a certain position of the cell and has the maximum sound absorption.In the case of different area ratio,the metamaterial still has a relatively matching acoustic impedance.Almost all the incident energy can be forced to flow to the resonant cell to enhance the cell vibration and still maintain a good sound absorption effect.When the thickness of the sheet becomes smaller or the height of the mass increases,the peak frequency of the sound absorption coefficient will shift to low frequency.Finally,the low frequency and wide band sound absorption of underwater 100-500 Hz is realized by reasonably designing and optimizing the parameters of thin plate metamaterials.

关 键 词：低频 大宽带 吸声 面积比 

分 类 号：TB56[交通运输工程—水声工程]