含坑点腐蚀的深海耐压球壳有限元分析

摘要

对于含坑点腐蚀等局部缺陷的球壳结构,由于结构的不连续性以及缺陷部位应力状态的三维特性,因此很难用传统的连续介质理论及板壳理论进行求解.为了对含坑点腐蚀的球壳的强度、稳定性进行精确分析,文中分别采用坑点腐蚀壳体单元(Pitting Corrosive Shell Element,PCSE)、基于多点约束(Multipoint Constraint,MPC)的壳体单元一实体单元集成以及实体单元三种方法进行对比计算,对比结果表明,采用PCSE方法的计算效率最高,且计算结果的精度满足工程应用要求.最后,基于PCSE方法并通过方差分析,讨论了坑点腐蚀对球壳强度及稳定性的影响.%It is hard to analyse sphere shell with pitting corrosion by traditional continuous medium theory and shell mechanics theory because of structure discontinuous and 3D stress status. The strength and buckling analysis of sphere shell with pitting corrosion were carried out by Pitting Corrosive Shell Element,shell-solid assemble based on Multipoint Constraint and solid element respectively, and the computation efficiency and precision were also compared among the three FE analysis methods. The results show that PCSE is the most efficient and the results precision can meet the needs of engineering application. Finally, the influences of pitting corrosion on the strength and buckling of sphere shell was discussed via PCSE and variance analysis.