Journal of Fluids and Structures 18 (2003) 227–250
Reduced-order models for nonlinear vibrations of cylindrical
shells via the proper orthogonal decomposition method
Abstract
The nonlinear (large-amplitude) response of perfect and imperfect, simplysupported circular cylindrical shells to harmonic excitation in the spectral neighbourhood of some of their lowest natural frequencies is investigated. The shell is assumed to be completelyfilled with an incompressible and inviscid fluid at rest. Donnell’s nonlinear shallow-shell theoryis used, and the solution is obtained bythe Galerkin method. The proper orthogonal decomposition (POD) method is used to extract proper orthogonal modes that describe the system behaviour from time-series esponse data. These time series have been obtained via the conventional Galerkin approach (using normal modes as a projection basis) with an accurate model involving 16 degrees of freedom, validated in previous studies. The POD method, in conjunction with the Galerkin approach, permits a lower-dimensional model as compared to those obt ainable via the conventional Galerkin pproach. Different proper orthogonal modes computed from time series at different excitation frequencies are used and solutions are compared. Some of these sets of modes are capable of describing the system behaviour over the whole frequencyrange around the fundamental resonance with good accuracy and with only3 degrees of freedom. Theyallow a drastic reduction in the computational effort, as compared to using the 16 degree-offreedom model necessarywhen the conventional Galerkin approach is used. r 2003 Elsevier Ltd. All rights reserved.
发表于 2006-6-2 08:08
提升卡
变色卡
显身卡
发表于 2006-6-21 08:06
