一种耦合算法的三维弹性空腔声振特性分析

针对三角形单元边界适应性强、位移插值简单、自由度低的特点，利用面积坐标构造了平板三角形单元位移插值函数，以对平板进行了动力学建模分析。此后，为了对三维弹性空腔声振问题进行较高精度的数值分析，弹性板采用三角形单元进行离散处理，而声腔域使用了在声学问题上具有精度高的光滑有限元方法建模。充分考虑结构和声场的耦合作用，建立了该类结构声振分析的一种新模型，并分析了弹性空腔声振特性。通过数值计算对比表明，这种耦合模型计算规模较小、计算结果精确，可进一步应用于形状更复杂的三维弹性空腔声振特性分析中。

Analysis of Vibro-acoustic Characteristics of Three-dimensional Elastic Cavity Based on a Coupling Algorithm

According to the characteristics of the triangular plate element with fine boundary adaptability, simple interpolation displacement function, and low freedom degrees, the area coordinate of the element is adapted to obtain the displacement interpolation function of the plate, so that the dynamic modal of the plate is achieved and analyzed. Then, in order to discuss the vibro-acoustic problem of the three-dimensional elastic cavity with high precision, the triangular plate element is used to discretize the elastic plate domain, whereas the smooth finite element method with high accuracy is applied in the acoustic cavity domain. Considering the coupling interaction between the plate and acoustic cavity, a new model for the three-dimensional elastic cavity is obtained, and the vibro-acoustic characteristics for it is demonstrated. Numerical results with comparison show that the calculation scope is smaller with accurate precision. Furthermore, it can be applied to the analysis on the vibro-acoustic characteristics of more complex three-dimensional elastic cavities.