SCALED BOUNDARY FINITE ELEMENT METHOD FOR ACOUSTICS

Abstract

When studying unbounded wave propagation phenomena, the Sommerfeld radiation condition has to be fulfilled. The artificial boundary of a domain discretized using standard finite elements produces errors. It reflects spurious energy back into the domain. The scaled boundary finite element method (SBFEM) overcomes this problem. It unites the concept of geometric similarity with the standard approach of finite elements assembly. Here, the SBFEM for acoustical problems and its coupling with the finite element method for an elastic structure is presented. The achieved numerical algorithm is best suited to study the sound propagation in an unbounded domain or interaction phenomena of a vibrating structure and an unbounded acoustical domain. The SBFEM is applied to study the sound transmission through a separating component, and for the determination of the sound field around a sound insulating wall. The results are compared with a hybrid algorithm of Finite and Boundary Elements or with the Boundary Element Method, respectively.