基于有限元理论,建立内壁含椭球形凹坑的厚壁圆筒有限元模型,模拟厚壁圆筒自增强过程的应力应变。采用三种不同的方法计算含凹坑缺陷的自增强厚壁圆筒的结构极限载荷,给出不同尺寸缺陷对极限载荷的影响规律。通过对比自增强与非增强条件下的极限载荷,表明自增强技术不能有效提高厚壁圆筒的极限承载能力,但在结构极限载荷下,含凹坑缺陷的自增强厚壁圆筒存在一个缺陷尺寸相对不敏感区,对提高结构的安全性是有利的。
Based on the finite element (FE) model of thick-wall cylinder with part-through slots, three high efficient methods were adopted to analyze the plastic limit load of autofrettaged thick-wall cylinder with slots and calculate the strain and stress under limit loading. According to the results of autofrettaged thick-wall cylinder plastic limit loads under different slots sizes, the autofrettage process has very little effect on increasing the limit load of the thick-wall cylinder. But the autofrettaged thick-wall cylinder has an insensitive zone of slots size and benefits the structural safety.