テーパ管付空洞形消音器の消音性能 : 挿入損失の理論と実験

概要

論文の詳細を見る
In ventilation systems, expansion-chamber silencers with tapered connectors at either end or both ends of the chambers are widely used to minimize the aerodynamic noise and the pressure drop of an air flow with the objective of reducing blower noise. The insertion-loss equations for the several types of these silencers were derived by using the four terminal constants of the equivalent electrical networks of the whole duct systems, with the aim of obtaining a method for predicting their acoustical performance by taking the duct effects into consideration. The results of the calculations by the derived equations agreed fairly well with the results of the experiments made at room temperature and without a flow, so far as the sound wave in the chamber can be regarded as a plane wave. The levels of the respective maximum values of the insertion loss for the individual tested silencers are similar to those for the cases of the transmission loss characteristics previously investigated, regardless of the change of the duct length and the setting position of the silencers.
東海大学の論文