Abstract
This paper describes the prediction on attenuation of a silencer tower with many resonators by using FEM. The purpose of this study is to realize the reduction of infra-sound which generates in various plants. The attenuation is firstly predicted by a conventional method and secondary calculated by FEM. In modeling of FEM, optimal mesh number is determined so that the variation of the natural acoustic frequency becomes within 10% of the detail model by calculating of various mesh models. Because the fine mesh model consumes much time to calculate. Finally, the experiment is performed and the calculated result is compared with the experimental one. As a result, it was clarified that the attenuation of a complex silencer with many resonators could be predicted by FEM. And the conventional method could also be predicted by taking into account of 70% the value of the calculated result.