Changes in Coupled Vibration Frequencies and Modes of Wall-Cavity Systems Induced by Stiffness Variation in the Structure

作     者：Soraya Mendes de Souza Lineu Jose Pedroso Paulo Marcelo Vieira Ribeiro 

作者机构：College of Technology University of Brasilia Brasilia 70904-108 Brazil Civil Engineering Department University of Pernambuco Recife 50740-530 Brazil 

出 版 物：《Journal of Civil Engineering and Architecture》 (土木工程与建筑（英文版）)

年 卷 期：2013年第7卷第9期

页      面：1111-1117页

学科分类：08[工学] 080103[工学-流体力学] 081402[工学-结构工程] 080104[工学-工程力学] 081304[工学-建筑技术科学] 081502[工学-水力学及河流动力学] 0815[工学-水利工程] 0813[工学-建筑学] 0814[工学-土木工程] 0801[工学-力学（可授工学、理学学位）] 

主　　题：Fluid-structure finite element vibration modes acoustic cavities. 

摘      要：Problems of fluid structure interactions are governed by a set of fundamental parameters. This work aims at showing through simple examples the changes in natural vibration frequencies and mode shapes for wall-cavity systems when the structural rigidity is modified. Numerical results are constructed using ANSYS software with triangular finite elements for both the fluid （2D acoustic elements） and the solid （plane stress） domains. These former results are compared to proposed analytical expressions, showing an alternative benchmark tool for the analyst. Very rigid wall structures imply in frequencies and mode shapes almost identical to those achieved for an acoustic cavity with Neumann boundary condition at the interface. In this case, the wall behaves as rigid and fluid-structure system mode shapes are similar to those achieved for the uncoupled reservoir case.