抄録
We have proposed a concentrated mass model to perform a two-dimensional acoustic analysis. This model consists of masses, connecting springs, connecting dampers and based support dampers. In our previous report, we proposed a concentrated mass model for a coupled system which consists of acoustic space and a membrane and verified the validity of the model. However, the result of eigenvalue analysis by this model includes some modes which are physically inappropriate, such as spurious modes or zero frequencies. In this paper, a spurious mode removal model for a coupled system is proposed. The result of eigenvalue analysis agrees with modes calculated by FEM model and doesn't contain those inappropriate modes. Furthermore, the degree of freedom of this model can be reduced keeping its matrix symmetrical and its calculation time is faster than FEM's which has asymmetrical matrices. Therefore, it is concluded that the proposed model is valid for the coupled analysis of acoustic and vibration.
