乏燃料贮存格架流固耦合参数的数值模拟

摘要

乏燃料贮存格架是储存乏燃料组件的重要设备.在地震载荷下,其响应是非线性的,可能产生滑移、颠覆等.发生地震时,存在于格架间隙内的流体耗散了结构的能量,保证了格架的完整性.本文使用3/10缩比模型,利用CFD软件Fluent进行了乏燃料贮存格架2D瞬态分析.计算过程中利用动网格方法模拟格架强迫振动,并进行了参数不确定性分析.利用CFD瞬态流体力分别获得了双Ⅱ区、双Ⅰ区格架附加质量矩阵.利用同轴圆柱体附加质量的计算解与解析解进行对比验证,证明了本文计算方法的准确性.本文计算所得的附加质量矩阵可为乏燃料贮存格架结构动态软件提供流固耦合参数.%Spent fuel storage rack is an important equipment for storing spent fuel assembly.Under seismic conditions,the response of rack is nonlinear and may cause slippage,subversion,etc.,but fluid in these gaps dissipates racks' energy by fluid structure interaction,which ensures the structural integrity of the rack.In this paper,2D transient calculation on the 3/10 scale model of rack was conducted by using Fluent software.In the process of calculation,the dynamic mesh was used to simulate the forced vibration of the rack,and the parameter uncertainty was analyzed.By using CFD transient fluid force,the added mass matrices of double Ⅱ and double Ⅰ racks were obtained.Comparing the theoretical solution of the added mass with the analytical solution of the coaxial cylinder,the accuracy of the method in this paper was verified.The added mass matrices calculated in this paper can provide fluid structure interaction parameters for the dynamic software of spent fuel storage rack structure.