254 差分法による流体音の数値解析(G05-4 流体騒音,G05 流体工学)  [in Japanese] 254 Numerical Analysis for Aeroacoustics by using of a Finite Difference Method  [in Japanese]

Finite difference model is proposed to predict sounds induced by vortex in the wake of a body located in free stream in duct. Flow field around the body is calculated by applying a conventional scheme for incompressible fluid such as MAC scheme. To predict the aerodynamic sound, Lighthill's aeroacoustic analogy is applied. Extended Lighthill's wave equations introduced by Curie which takes into account the effect of the solid body are solved by Hancock scheme. In this study, we caluclated the flow around a elliptic cylinder in a duct to apply our scheme in a compact condition. The calculation can reproduce the propagation of dipole sound generated from the body and the reflection of one from the wall.