点阵夹芯圆柱壳自由振动分析的波有限元方法OACSTPCD

A wave finite element method was developed for the free vibration analysis of lattice core sandwich cylindrical shells.Firstly,based on the propagation law of free waves,governing equations for a core element of the lattice core sandwich cylindrical shell was established.Compared with the full-scale finite element mod-el,degrees of freedom of the governing equations for a core element are significantly reduced.Secondly,an ex-plicit expression for the inverse of the constrained dynamic stiffness matrix was derived based on the Neumann series,which not only improves computation efficiency but also separates the natural frequency from the gover-ning equations,thereby transforming the natural frequency solution of the lattice core sandwich cylindrical shell into a quadratic eigenvalue problem of a core element.Finally,according to the relationship between the struc-tural vibration mode and the free wave,the expressions of the axial and circumferential wave propagation pa-rameters of the cylindrical shell were given,and the natural frequencies and modes of the lattice core sandwich cylindrical shell were obtained.Numerical examples of the free vibration analysis on a lattice core sandwich cy-lindrical shell under different boundary conditions verify the validity and efficiency of the proposed method.