吊篮振动特性对压紧弹簧的参数敏感分析

Sensitivity Analysis of the Dynamical Characteristics of a Core Barrel to the Compressive Spring Parameters

采用ANSYS程序建立反应堆吊篮在空气中的有限元模型,计算其在空气中的振动特性。重点研究压紧弹簧刚度对反应堆吊篮的振动特性影响。计算结果表明压紧弹簧的弯曲刚度和扭转刚度对吊篮结构的一阶梁式和轴向振动频率有明显的影响,刚度的存在使得结构的这几阶频率明显增大,对结构振型出现的先后顺序没有变化。在一定区域范围内随着压紧弹簧弯曲刚度的增加,吊篮的一阶梁式和轴向振动频率明显增加而吊篮的壳式振动频率几乎不受压紧弹簧弯曲刚度的影响。

ANSYS was applied to establish the model of a core barrel of nuclear reactors in air, and dynamical characteristics were calculated. The influences of the compressive spring stiffness on the dynamical characteristics of the core barrel were mainly concerned. The results show that the bending stiff-ness and torsional stiffness of the compressive spring have obvious influence on the first-order beam and axial-deformation frequencies. These two types of frequencies increase when the stiffness of compressive spring is considered while the orders of the modal remain the same. During a certain area, with the increase of the compressive spring stiffness, the first-order beam and axi-al-deformation frequencies increase, and the changing of the compressive stiffness have little in-fluence on the shell frequencies of the structure.