title: Numerical analysis of eigenproblem for cavities by a particular integral method with a low frequency approximation of surface admittance.
abstract: In this paper, a three-dimensional boundary element method for the eigenanalysis of complex-shaped cavity is presented. A particular integral method is proposed with general absorbing boundary conditions, well suited for determination of the lower modes. In this approach, a polynomial approximation of surface admittance is used with a recent class of compactly supported radial basis function. Two common absorbent models are employed in order to demonstrate the relevance of high-order approximation of the admittance. Resulting eigenproblems of several orders (linear to cubic) are thus performed on basic geometries and a car interior. Results show significant improvements for the computed damped eigenfrequencies and the associated modal reverberation time while using an approximation polynomial matching the surface admittance variation order.
authors.affiliation: UArtois, LGCgE, F-62400 Béthune, France. alexandre.leblanc@univ-artois.fr
authors.forename: Alexandre
authors.initials: A
authors.lastname: Leblanc
authors.forename: Antoine
authors.initials: A
authors.lastname: Lavie