中文摘要：

利用有限元模拟方法建立了U O2弥散型燃料颗粒受内部多个气泡内压作用的模型，计算得到了燃料颗粒内部存在多个气泡时的应力分布结果。结果表明，当气泡沿 x轴均匀排列时，y方向的最大正应力随气泡数量的增多而增大，且增大幅度逐渐减小，气泡对燃料颗粒内部最大正应力的影响存在极限；当存在多行气泡时，燃料颗粒内部 x方向的最大正应力随气泡行数的增加而增大，y方向的最大正应力随气泡行数的增加而减小；气泡造成的燃料颗粒内部的应力集中效应随距径比的增大而减小。

英文摘要：

The finite element model was proposed to simulate the process of the UO 2 dis‐persion fuel particle sustaining the internal pressure of multi‐bubbles ,and the stress distribution of fuel particle with intra‐bubbles was calculated .The results show that when the bubbles line equidistantly along x axis ,the max normal stress along y axis increases with the number of bubbles ,meanwhile ,the increment of the normal stress gradually decreases .There is a limit that the effect of bubble’s number imposes on the max normal stress in the fuel particle .When multi‐column of bubbles exist ,the max normal stress along x axis in the fuel particle increases ,and the max normal stress along y axis decreases with the increase of the number of bubble column .The stress concen‐tration in the fuel particle decreases with the spacing radius ratio increasing .