Acoustic Characteristics of Sound Field in Cylindrical Enclosure with Exciting End Plates.

Abstract

This paper describes the coupling of the vibration of exciting circular end plates and the sound field in a cylindrical enclosure. Assuming that the lateral wall of the cylindrical structure is rigid, a theoretical analysis is carried out for the relative amplitude and the phase difference as to both exciting forces, which influence the coupling of the vibration of the end plates and the sound field. If the vibration modes of both end plates are coincide with the different acoustic modes of the sound field with respect to the circumferential order, the distribution of the sound field has the complex nature of some acoustic modes. The distribution depends on the relative amplitude of both exciting forces. Coupling with the same vibration mode of both end plates, the acoustic modes with the cylindrical length orders are restrained from dominating the odd orders by the exciting forces of the same phase, while the inverse phase makes the even orders restrained.