A reduction method for structure-acoustic and poroelastic-acoustic problems using interface-dependent Lanczos vectors

A reduction method is proposed for analysing structure-acoustic and poroelastic-acoustic problems within a finite element framework. This includes systems consisting of an acoustic fluid domain coupled to a flexible structural domain and/or a porous sound absorbing material domain. The studied problem is reduced by dividing the system into a number of physical subdomains. A set of basis vectors is derived for each of these subdomains, including both normal modes and interface-dependent vectors that take account of the influence of connecting subdomains.The method is verified in two numerical examples using the proposed method for both solving the structure-acoustic eigenvalue problem and performing a frequency response analysis in an acoustic cavity with one wall covered by porous material.