CAJ | 학술논문

基于分层理论，建立了四边简支约束条件下薄板声辐射特性有限元分析模型，计算了其固有频率、辐射声功率及振动均方速度，并与 Comsol 软件计算结果进行对比，证明了该方法的有效性。其次，将分层理论用于贴敷阻尼薄板的声辐射特性研究中，分析了单/多层阻尼对结构声辐射特性的影响。最后，通过分析贴敷阻尼薄板在轻/重流体、不同流速条件下的声辐射特性，研究了流体对贴敷阻尼薄板声辐射特性的影响。结果表明，贴敷多层阻尼的薄板结构声辐射特性对阻尼材料贴敷顺序较为敏感，将弹性模量较大的阻尼材料贴敷在靠外侧能够增大约束阻尼层的剪切变形，有利于提高结构整体的损耗因子，降低结构的振动和声辐射；流体流动时，结构声振特性将发生非线性变化，当流速较低时，结构声振特性变化明显，随着流速增大，变化趋势趋于平稳。
기우분층이론，건립료사변간지약속조건하박판성복사특성유한원분석모형，계산료기고유빈솔、복사성공솔급진동균방속도，병여 Comsol 연건계산결과진행대비，증명료해방법적유효성。기차，장분층이론용우첩부조니박판적성복사특성연구중，분석료단/다층조니대결구성복사특성적영향。최후，통과분석첩부조니박판재경/중류체、불동류속조건하적성복사특성，연구료류체대첩부조니박판성복사특성적영향。결과표명，첩부다층조니적박판결구성복사특성대조니재료첩부순서교위민감，장탄성모량교대적조니재료첩부재고외측능구증대약속조니층적전절변형，유리우제고결구정체적손모인자，강저결구적진동화성복사；류체류동시，결구성진특성장발생비선성변화，당류속교저시，결구성진특성변화명현，수착류속증대，변화추세추우평은。
The finite element method based on the layerwise theory was employed to model a thin simply supported plate.Its natural frequencies,sound radiation power and the mean square vibration velocity calculated agreed well with those using Comsol software.The layerwise theory was then used to analyze the influence of single /multi-layer viscoelastic material on the vibro-acoustic properties of the thin plate.The influences of fluid mass density and flow velocity on the characters of fluid were investigated as well.The results showed that the sound radiation is sensitive to the stacking sequence of damping layers;it is better to stack the layer with higher young’s modulus on the out board,it can increase the structural acoustic radiation loss factor and reduce the sound radiation power;in addition,the vibro-acoustic characteristics of the thin plate in a fluid have a nonlinear change when fluid flows,they vary obviously when flow velocity is slow and they tend to be stable with increase in flow velocity.