摘要
基于三维有限元的时域仿真法,探讨了建立声学结构单元传递函数模型的一般方法。所建立的声学单元传递函数由结构参数高精度表达,能简化一般声学结构设计问题的流程。首先,建立了两种声学结构单元,仿真其幅频特性,并结合试验测量,验证幅频特性曲线的准确性,而后基于幅频特性曲线拟合传递函数,选择精度最高的零极点匹配方案,确定拟合传递函数的最优型式。结果表明,匹配7个极点和无零点来拟合膨胀腔单元的传递函数,匹配2个极点和2个零点来拟合亥姆霍兹共振腔单元的传递函数,拟合精度最高。然后,分析声学单元的结构参数对幅频特性的影响,并基于拟合传递函数的最优型式,通过数值仿真和拟合计算,建立由结构参数表达的声学结构单元传递函数模型。最后,构造了由膨胀腔和亥姆霍兹共振腔构成的复合声学结构,通过单元传递函数的组合计算,获得声学结构的总传递函数,并与COMSOL仿真结果比较,验证所建立声学单元传递函数模型的正确性,它能准确描述声学结构的传递损失特性。
The transfer function model of an acoustic structural unit was established through the time-domain simulation by using three-dimensional finite element analysis,and was accurately expressed as a function of structural parameters.The transfer function representation can simplify the design process of acoustic structures.First,two acoustic structural units were designed,and their amplitude-frequency characteristics were simulated.Meanwhile,the simulated amplitude-frequency characteristics were verified byexperimental measurements.Next,based on the amplitude-frequency characteristics,the transfer functions of the two structural units were fitted by adopting different zero-pole matching schemes.The results show that the fitting accuracy is the highest when matching 7 poles and no zero to fit the transfer function of the expansion chamber unit,and matching 2 poles and 2 zeros to fit the transfer function of the Helmholtz resonator unit.Then,the influences of the structural parameters of the acoustic unit on the amplitude-frequency characteristics were analyzed.Subsequently,based on the high accuracy form of the fitted function,the transfer function model of the acoustic structural unit is established by numerical simulation and fitting calculation.Finally,a composite acoustic structure composed of an expansion chamber and a Helmholtz resonator was constructed,and its transfer function was calculated based on the transfer function models of the units.The results of COMSOL and the transfer function model were compared to verify the accuracy of the established unit transfer function models.
作者
张本熙
王晓明
梅玉林
ZHANG Benxi;WANG Xiaoming;MEI Yulin(School of Mechanical Engineering,Dalian University of Technology,Dalian 116024,China;School of Automotive Engineering,Dalian University of Technology,Dalian 116024,China)
出处
《振动与冲击》
EI
CSCD
北大核心
2024年第10期174-184,196,共12页
Journal of Vibration and Shock
基金
国家自然科学基金(51975083,51775080,11372059,11272073)。
关键词
时域
声学结构
膨胀腔
亥姆霍兹共振腔
传递函数
time domain
acoustic structure
expansion chamber
Helmholtz resonator
transfer function
