初始缺陷对深海载人潜水器耐压球壳塑性稳定性影响

载人深潜器耐压球壳是中厚度壳结构,当结构发生失稳时,球壳结构的局部部位因为材料达到屈服极限而发生了塑性变形.将有限元分析与经典理论相结合,研究弹性屈曲模态缺陷、局部缺陷以及球壳整体圆度和厚度偏差对中厚度球壳结构的塑性稳定性的影响.计算结果表明中厚度球壳结构对初始缺陷并不很敏感,对球壳结构当局部缺陷范围刚好达到临界弧长时结构的承载力最弱.通过缺陷结构和完善结构的极限承载力比较,提供了初始缺陷影响曲线.

Influence of initial deflection on plastic stability of manned deep-sea submersible's pressure sphere hull

The pressure sphere hulls of the manned deep-sea submersibles are mid-thick hulls. The material yields in the location of the hulls before the structures fail. Combining the finite element analysis with the typical theory, the article studies the influence of the eigenvalue-buck- ling-mode imperfection, local imperfection, and the deflection of thickness and radius. The results show that the structures are not sensitive to the initial imperfection. The critical loads are the worst when the range of the imperfection is the critical are-length. Comparing the imperfect structures with the perfect structures leads to the influencing curve.