インピーダンス境界面に接するダクト内の高周波音波伝搬

概要

論文の詳細を見る
A high-frequency sound field in a duct with a monotonically increasing velocity profile over an impedance boundary is investigated by four methods:1)boundary wave mode, continuous spectrum, and surface wave mode(surface trapped mode)representation, 2)geometrical acoustical ray, interference wave expressed in integral form, and surface wave mode representation, 3)geometrical acoustical ray, lower order boundary wave mode, and surface wave mode representation, and 4)near field perturbation representation. Numerical evaluations and physical interpretations of these alternative methods are performed for a specific example with a slowly increasing exponential velocity profile. As for planar impedance boundary problems, the total sound field is enhanced and an interference effect appears due to the existence of a surface trapped mode for a highly inductive impedance boundary. Most interesting from a physical view point is a field representation consisting of a few geometrical acoustical rays, lower order boundary wave modes, and a surface wave mode
社団法人日本音響学会の論文
1985-07-01