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 the previous report, the result of eigenvalue analysis by this model includes some spurious values and zero natural frequencies. In this paper, a spurious mode removal model which is changed the distribution of masses is proposed to analyze natural frequencies without spurious values. Furthermore, this model can be reduced order to remove zero natural frequencies. To confirm the validity of proposed model, the numerical results by this model are compared with the theoretical values in time domain and frequency domain. All results agree with theoretical values. Furthermore, spurious values and zero natural frequencies are removed in eigenvalue analysis. Therefore, it is concluded that the proposed model is valid for two-dimensional acoustic analysis.
