摘要
为了量化评估两种功能型材料的声振性能,基于结构有限元(FEM)法和声学边界元(BEM)法,计算出典型环肋圆柱壳的振动声辐射,结果与文献试验值的一致性较好。进行动态热力学实验并基于温频等效原理,得到了黏弹性吸声芯材的动态力学参数;采用流体有限元法模拟水和圆柱壳的耦合作用,最后采用间接边界元法计算了点激励作用下不同功能材料夹芯壳辐射声场。结果表明:周向模态对浮力材料夹芯壳和吸声材料夹芯壳模态阻尼比均有重要的影响,轴向模态仅对吸声材料的夹芯壳模态阻尼比有显著影响;与等质量的钢壳相比,浮体材料夹芯壳的最大声功率降低21.38 d B,吸声材料夹芯壳的最大声功率降低56.55 d B;将两种功能材料按比例组合作为夹芯材料,壳体的辐射声功率随着吸声材料占比的增加而降低,但是降低的幅度不断减小。
In order to evaluate the acoustic-radiation performance of two functional materials, the vibro-acoustic radiation of a typical cylindrical shell with stiffened ring ribs is calculated based on FEM and BEM method, and the results agree well with the experimental results. According to the equivalent principle of temperature and frequency, the dynamic mechanical parameters of viscoelastic core material for acoustic absorption were acquired from the results of dynamic thermodynamic experiments. The coupling effect of water and the shell was simulated by finite element method. Finally, the acoustic radiation field of sandwich-shells with different core materials excited by a point source was calculated by means of indirect boundary method. The results show that the circumferential mode has an important influence on the modal damping ratio of both the sandwich shell with buoyancy core and sandwich shell with sound-absorption core, whilst axial mode just has a significant effect on the modal damping ratio of the sandwich shell with sound-absorption core. The peak value of the acoustic power of the sandwich shell with buoyancy core and sandwich shell with sound-absorption core is 21.38 d B and 56.55 d B lower than that of the steel shell respectively. When the combination of the above two functional materials in different proportion were used as the core material, the radiation acoustic power decreases with the increasing proportion of the sound-absorption material, but the decrease amount diminishes gradually.
出处
《材料研究学报》
EI
CAS
CSCD
北大核心
2017年第6期458-464,共7页
Chinese Journal of Materials Research
基金
国家部委基金(9140A14080914JB11044)~~
关键词
复合材料
夹芯壳
有限元
边界元
振动声辐射
composite
sandwich shell
finite element method
boundary element method
vibroacoustic
