Abstract
A method for measuring an oblique incidence absorption coefficient is proposed in this paper. Time streched method is generally used to measure it. But this method needs large specimen and wide area to separate direct acoustic wave and reflex wave. We tried to study the applicability of short acoustic tube to measure it through experiment, one dimensional theoretical analysis and three-dimensional numerical analysis. We found that proposed method is applicable under the incident angle 45 degree, if the surface of the material is locally reactive.
