工业辐照放射源运输货包事故条件下冲击试验的数值模拟

Numerical Simulation on Impacting Test of Industrial Irradiation Transport Package for Radioactive Material Under the Accident Condition

为验证放射性物质运输货包结构设计的安全性,建立了事故条件下货包自由下落冲击刚性靶面的全尺寸有限元模型。采用非线性动力显式算法,对货包在事故条件下以顶角、侧面和顶面3种姿态冲击刚性靶的力学试验进行了数值模拟,重点分析了货包冲击后的整体变形和应力分布,以及连接螺栓的强度;在3种跌落姿态下,容器内壳应力最大值为154.9MPa,容器外壳等效塑性应变最大值为0.24。依据货包安全设计准则,容器内壳与外壳的应力应变强度均未超出许用值。研究获得了货包结构的冲击强度和变形,预测了货包最危险的下落姿态,为后续验证性试验提供科学的依据。

Mechanical test for the free drop of transport package of radioactive material is one of the significant tests for verifying package structure design. The full-scale finite element models of package impacting on the rigid target were established under accident conditions. The impacting tests of package on the rigid target with three different types of postures such as top corner, lateral plane and top plane were simulated by nonlinear dynamic explicit algorithm. The general deformation and stress distribution of package,and the bolt strength were emphatically analyzed. In the three postures,the maximum stress of inner container is 154.9 MPa, the maximum equivalent plastic strain of outer container is 0.24. According to the package design criteria,the package inner and outer shell stress and strain did not exceed allowable values. The impact strength and deformation of package structure were obtained and the most dangerous drop postures was esti-mated. It is a basis of the subsequent drop test.