A coupled BEM and energy flow method for mid-high frequency internal acoustic

Sébastien Besset (1) , Mohamed Ichchou (1) , Louis Jezequel (1)

1 LTDS - Laboratoire de Tribologie et Dynamique des Systèmes

This paper deals with the behavior of acoustic cavities in the mid-high frequency range. The method proposed here is based on an energy flow method named Simplified Energy Method (MES). MES method is quite efficient in the mid-high frequency range but the directivity of the boundary sources is not well estimated. We propose a hybrid method which couples MES and the Boundary Element Method (BEM). Thus, the BEM method is used to estimate the direct field, considering a "correct" directivity. As a complete calculation is not adapted to BEM in mid-high frequency range because of the calculation costs, we only apply BEM on the domains including boundary sources. Other parts of the system and the reverberated field are estimated by the mean of MES method. This hybrid method leads to a consistent prediction of injected power densities. Numerical comparisons prove the efficiency of the proposed reformulation.

Mots clés: Energy flow; BEM; energy method; injected power density; energy density; intensity

Domaines: Mécanique des structures [physics.class-ph]; Mécanique des structures [physics.class-ph]; Vibrations [physics.class-ph]; Vibrations [physics.class-ph]; Acoustique [physics.class-ph]; Acoustique [physics.class-ph]

Sébastien Besset, Mohamed Ichchou, Louis Jezequel. A coupled BEM and energy flow method for mid-high frequency internal acoustic. Journal of Computational Acoustics, 2010, 18 (1), pp.69-85. ⟨10.1142/S0218396X10004073⟩. ⟨hal-00625137⟩