基于区域分解的环肋圆柱壳-圆锥壳组合结构振动分析  

Vibration analysis of ring stiffened cylindrical-conical shell structures based on a domain decomposition method

作　　者：瞿叶高[1] 谌勇[1] 龙新华[1] 华宏星[1] 孟光[1] 

机构地区：[1]上海交通大学机械系统与振动国家重点实验室,上海200240

出　　处：《计算力学学报》2013年第1期166-172,共7页Chinese Journal of Computational Mechanics

摘　　要：提出了一种区域分解法来分析不同边界条件下环肋骨圆柱壳-圆锥壳组合结构的振动特性。首先把组合壳体分解为自由的圆柱壳、圆锥壳段;视环肋骨为离散元件,根据肋骨与圆柱壳段之间的变形协调条件,将肋骨的动能和应变能附加于圆柱壳段能量泛函中。然后基于分区广义变分和最小二乘加权残值法将所有分区界面的位移协调方程引入到组合壳体的能量泛函中。圆柱壳段、圆锥壳段位移变量的周向和轴向分量分别采用Fourier级数和Chebyshev多项式展开。以自由-自由、自由-固支和固支-固支边界条件的环肋骨组合壳体为例,采用区域分解法分析了其自由振动及在不同激励下的振动响应。通过与有限元软件ANSYS结果进行对比,发现两种方法计算结果非常吻合,验证了区域分解方法的计算精度和高效性。A domain decomposition approach is proposed for vibration analysis of ring stiffened cylindri- cal-conical shell （CCS） structures subjected to various boundary conditions. A stiffened CCS is divided into some stiffened-cylindrical and conical shell segments along the locations of the junctions and the geometry boundaries. The ring stiffeners are treated as discrete elements. The energy functional of a stiffened-cylindrical shell segment is obtained by appending the kinetic energy and strain energy of the rings to that of the attached shell from geometrical continuity considerations. All interface continuity constraints are incorporated into the system potential functional by means of a subdomain generalized variational principle and least-squares weighted residual method. Double mixed series, i. e. the Fourier series and Chebyshev orthogonal polynomials,are adopted as assumed admissible displacement functions for each shell segment. Free and forced vibrations of stiffened CCSs are examined under free-free, freeclamped and clamped-clamped boundary conditions. The numerical results obtained from the present method show good agreement with those from the finite element program ANSYS. The present solution is very efficient, robust and accurate.

关 键 词：区域分解 分区广义变分 最小二乘加权残值 圆柱壳-圆锥壳组合壳体 自由振动 强迫振动 

分 类 号：TH113[机械工程—机械设计及理论] TU33[建筑科学—结构工程]