High precision interval analysis of the frequency response of structural-acoustic systems with uncertain-but-bounded parameters

The recently developed edge-based smoothed finite element method (ES-FEM) is an efficiency method for solving frequency response of structural-acoustic systems with nominally deterministic parameters. In order to further dealing with the unavoidable uncertainties, both the interval perturbation techniques and the subinterval perturbation techniques are introduced and embedded into the hybrid edge-based smoothed finite element method for structural-acoustic systems with uncertain-but-bounded uncertainties in this work. Firstly, the structural subsystems are described by using 2D edge-based smoothed finite element method; meanwhile, the acoustic subsystems are established by using 3D edge-based finite element method. Then the interval perturbation technique is introduced to establish the interval perturbation equations of structural-acoustic coupled system with small uncertain level. For parameters with large uncertain level, the subinterval perturbation technique is further embedded to improve the computational accuracy (named SIPES-FEM/ES-FEM). The results obtained by IPES-FEM/ES-FEM and SIPES-FEM/ES-FEM are compared with results obtained by Monte-Carlo method. The higher computational accuracy and efficiency of the proposed IPES-FEM/ES-FEM and SIPES-FEM/ES-FEM are verified by two numerical examples.