123 コニカル型多孔群を通過する微小噴流と相互作用する音波の吸音特性(吸音・遮音構造)

Abstract

This paper describes the experimental investigation on the acoustic absorption caused by interaction of sound waves with fine-scale jets through conical holes. The experiments were carried out on three types of perforated plate: one has the straight holes, another have semi-conical and conical. The experimental results showed that the absorption was enhanced by not only the fine-scale jets through the perforated plate but also the effect of cross sectional area of the holes. The fine-scale jets through the conical holes provided a better absorption coefficient over a wide frequency range.