Department of Mechanical Engineering, University of Bristol, Bristol BS8 1TR, United Kingdom.
J Acoust Soc Am. 2010 Sep;128(3):1004-14. doi: 10.1121/1.3467775.
A robust and efficient technique for predicting the far-field scattering behavior for an arbitrarily-shaped defect in a generally anisotropic medium is presented that can be implemented in a commercial FE package. The spatial size of the modeling domain around the defect is as small as possible to minimize computational expense and a minimum number of models are executed. The method is based on an integral representation of a wave field in a homogeneous anisotropic medium. A plane incident mode is excited by applying suitable forces at nodes on a surface that encloses the scatterer. The scattered wave field is measured at monitoring nodes on a concentric surface and then decomposed into far-field scattering amplitudes of different modes in different directions. Example results for 2D and 3D bulk wave scattering in isotropic material and guided wave scattering are presented. Modeling accuracy is examined in various ways, including a comparison with the analytical solutions and calculation of the energy balance.
本文提出了一种稳健高效的方法，用于预测各向异性介质中任意形状缺陷的远场散射行为，该方法可在商业有限元软件包中实现。建模域中缺陷周围的空间尺寸尽可能小，以最小化计算成本和执行的模型数量。该方法基于各向异性均匀介质中波场的积分表示。通过在包围散射体的表面节点上施加适当的力来激励平面入射模式。在同心表面上的监测节点测量散射波场，然后将其分解为不同方向不同模式的远场散射幅度。给出了各向同性材料中二维和三维体波散射以及导波散射的示例结果。通过多种方式检查建模精度，包括与解析解的比较和能量平衡的计算。
