title: Surface contributions to radiated sound power.
abstract: This paper presents a method to identify the surface areas of a vibrating structure that contribute to the radiated sound power. The surface contributions of the structure are based on the acoustic radiation modes and are computed for all boundaries of the acoustic domain. The surface contributions are compared to the acoustic intensity, which is a common measure for near-field acoustic energy. Sound intensity usually has positive and negative values that correspond to energy sources and sinks on the surface of the radiating structure. Sound from source and sink areas partially cancel each other and only a fraction of the near-field acoustic energy reaches the far-field. In contrast to the sound intensity, the surface contributions are always positive and no cancelation effects exist. The technique presented here provides a method to localize the relevant radiating surface areas on a vibrating structure. To illustrate the method, the radiated sound power from a baffled square plate is presented.
authors.affiliation: LRT4-Institute of Mechanics, Universität der Bundeswehr München, D-85579 Neubiberg, Germany. steffen.marburg@unibw.de
authors.forename: Steffen
authors.initials: S
authors.lastname: Marburg
authors.forename: Eric
authors.initials: E
authors.lastname: Lösche
authors.forename: Herwig
authors.initials: H
authors.lastname: Peters
authors.forename: Nicole
authors.initials: N
authors.lastname: Kessissoglou