典型结构的高频响应研究

HIGH-FREQUENCY RESPONSE RESEARCH OF CLASSICAL STRUCTURE

利用 NASTRAN软件得到一简支梁从低频到高频的频响特性 ,研究了不同有限元网格划分对结构高频特性的影响 ,并通过 SEA法、有法元法以及解析解的对比揭示了 SEA法在高频响应预示中的有效性。然后以耦合梁为例 ,通过有限元法得到两个梁之间的能量传递 ,并进而得到 SEA所需的耦合损耗因子 ;将有限元计算结果和 SEA结果对比验证了该方法的有效性 ,以期建立一种用有限元法获得 SEA参数的新途径。此外 。

The high frequency response characters of a simple supported beam is obtained by NASTRAN.The result is strongly influenced by the mesh size.The comparison based on FEM,SEA and the closed form solution reveals the effectiveness of SEA in the prediction of high frequency response.Next,the energy transmission between two coupled beams is obtained through FEM,and then the CLF used by SEA is built.The method is verified through the comparison between FEM and SEA in order to establish a new method which get the SEA parameter by FEM.Last,the effects of concentrated mass and boundary condition are considered.