反应堆结构三维非线性抗冲击分析

建立三维非线性有限元模型，对反应堆结构进行抗冲击动力响应分析，克服了结构的间隙、接触、摩擦、阻尼、预紧、碰撞、流固耦合、连接刚度等非线性因素；对于吊篮与压力容器间的流固耦合作用，建立水动力质量矩阵，并采用ANSYS声单元验证其准确性；设置了三维的堆芯上下板，并建立了多组燃料组件模型，考虑其预紧、跳起、与围板的间隙及碰撞，并考虑水平与竖直方向的耦合，更加精确地模拟了反应堆结构动力响应；以3个方向的冲击加速度时程作为计算输入，得到了各部件的响应，为各部件应力分析及控制棒驱动线抗冲击试验提供输入。该方法为反应堆结构的三维动力响应分析提供借鉴。 

Analysis of Three-Dimensional Nonlinear Impact on Reactor Structure

In order to analyze the dynamic response of the reactor structure, a three-dimensional nonlinear was established. The model overcame many nonlinear factors such as clearance, contact, friction, damping, pretension, impact, fluid-structure coupling and connection stiffness. Considering the fluid-structure coupling between the core barrel and the RPV, the hydrodynamic mass matrix was modeled and verified by ANSYS acoustic element. Three-dimensional upper core plate, lower core support plate was set up. Multi-group fuel assembly was built, which considered the preload and bounce with the core plate, the clearance and impact with the core shroud. The model accurately simulated the dynamic response of the reactor structure because of the coupling of horizontal and vertical directions. Finally, the response of each component was obtained by inputting the time history of the impact acceleration in three directions, which provided the input for the stress analysis of the components and the impact experiment of the control rod drive line. The method in this paper can offer a reference for the three-dimensional nonlinear dynamic analysis of the reactor structure.