外压柱壳有限元计算的探讨

DISCUSSION ON THE FEA OF CYLINDRICAL SHELL UNDER EXTERNAL PRESSURE

为了利用有限元分析方法解决特殊结构的外压稳定计算问题,对一般外压圆筒的稳定问题,分别以有限元分析方法与经典解及GB150图算法进行对比分析,结果发现外压有限元计算结果在定性上与经典理论公式吻合较好,数值上外压有限元法结果偏大,特别是针对短圆筒的外压计算。通过对非线性屈曲和特征值屈曲的对比,发现非线性屈曲计算结果和特征值屈曲计算相差不大,考虑到工程计算,采用特征值屈曲即可满足需求。

In order to use FEA method to solve the problems in the stability calculation of special structures under external pressure, FEA method is used to calculate cylindrical shell under external pressure with Eigen value buckling analysis and nonlinear buckling analysis. The Eigen value buckling analysis results are in good agreement with the theoretical results qualitatively,and the value calculated by Eigen value buckling analysis is 10% bigger than the theoretical results while the cylindrical shell is long and 30%~40% bigger while the cylindrical shell is short.The Eigen value buckling analysis results are a little bigger than the nonlinear buckling analysis results,and the difference can be neglected in engineering cases.