深海钛合金压力容器在静水压力作用下的弹塑性分析

Elastic-plastic analysis for the deep-sea Ti-alloy pressure vessel subjected to external hydrostatic pressure

利用MSC.Marc Mentat 2005通用有限元软件对深海探测用压力容器受静水压力作用时的弹塑性失稳问题进行了计算与分析,弹性失稳数值计算的结果与用现有规范计算公式所得结果一致,均大于塑性失稳数值分析时的临界载荷。由此得出结论,对于厚壁且形状复杂的压力容器的失稳计算,用理论公式或仅用厚壳单元的弹性失稳分析是不够的,应该用3维立体单元的弹塑性失稳计算才能给出比较精确的强度预测。MSC.Marc Mentat2005强大的计算和仿真功能有效地模拟了深海精密探测容器受静水压力作用时的弹塑性失稳问题,为深海精密探测容器在材料、外观等方面做进一步的设计改进提供了可靠的工具。

By using the general FEM software of MSC.Marc Mentat 2005, the elastic-plastic buckling analysis of deep-sea submarine pressure vessel was conducted. The critical load obtained from elastic buckling analysis is consisted with those from classical theories,and they are much larger than those from plastic buckling analysis.It shows that structural plastic buckling due to the high external hydrostatic pressure is dominant risk factor for deep-sea pressure vessel,and plastic buckling with three-dimensional 8-nodes iso-parameter elements is necessary to give a precise buckling prediction. MSC. Marc Mentat 2005 is efficient for the analysis of the deep-sea pressure vessel, and it provides a reliable method to improve the design of deep-sea pressure vessel further.