POLYNOMIAL CHAOS EXPANSION SENSITIVITY ANALYSIS FOR ELECTROMECHANICAL IMPEDANCE OF PLATE

摘要

Piezoelectric wafer active sensors (PWAS) have been the widely used in impedance based damage detection applications. A most important matter in impedance method is applied voltage to PWAS and measuring current in PWAS. In this paper, for modeling of impedance based structural health monitoring, a 3D spectral finite element method (SFEM) is developed for plate structure with PWAS. Because of high frequency application of impedance method, high degree of freedom (DOF) is needed for modeling of impedance of PWAS attached on the plate. Uncertainty of plate and PWAS parameters could be effect on the natural frequencies of structure. So, impedance signal of modeling would be different based on uncertainty parameters. Polynomial chaos expansion (PC) is a probabilistic method consisting in the projection of the model output on a basis of orthogonal stochastic polynomials in the random inputs. In this paper, PCE is used for sensitivity analysis of the electromechanical impedance of plate structure with PWAS.