燃料组件弯曲的高保真全堆芯中子学计算方法及应用  

High-fidelity Full Core Neutronics Calculation Method for Fuel Assembly Bowing and Its Application

作　　者：李帆[1] 刘宙宇[1] 王习宁 曹良志[1] 吴宏春[1] Li Fan;Liu Zhouyu;Wang Xining;Cao Liangzhi;Wu Hongchun(Department of Nuclear Science and Technology,Xi'an Jiaotong University,Xi’an,710049,China)

机构地区：[1]西安交通大学核科学与技术系,西安710049

出　　处：《核动力工程》2023年第4期9-16,共8页Nuclear Power Engineering

基　　金：中国核工业集团有限公司领创科研项目;国家自然科学基金项目(11753011,U2167205)。

摘　　要：为了研究燃料组件弯曲变形对堆芯功率分布的影响,提出了一种等效模拟压水堆堆芯内燃料组件弯曲的方法,即根据弯曲前后燃料组件四周的水隙材料的原子数目守恒原则,通过保持弯曲前后的水隙宽度不变,改变弯曲后水隙内所有核素的原子核密度,近似等效燃料组件弯曲后四周水隙的变化。通过蒙特卡罗程序NECP-MCX和确定论数值反应堆程序NECP-X对其正确性进行验证,并基于NECP-X程序对欧洲先进压水堆(EPR)全堆芯的燃料组件弯曲工况进行了模拟分析,计算结果表明:由于局部慢化效应变化,燃料组件小幅弯曲对堆芯功率分布影响相对较大,全堆芯问题中最大的偏移量在2 mm左右时可使组件功率的相对变化达到5%左右。In order to study the influence of bowing deformation of fuel assemblies on core power distribution,this paper proposes an equivalent method for simulating the bowing of fuel assemblies in PWR Core.That is,according to the principle of conservation of atomic number of the water gap material around the fuel assembly before and after bowing,the nuclear density of all nuclides in the water gap after bowing is changed by keeping the width of the water gap unchanged before and after bowing,which approximates the change of the water gap around the equivalent fuel assembly after bowing.Its correctness is verified by Monte-Carlo code NECP-MCX and deterministic numerical code NECP-X.Based on the deterministic numerical code NECP-X,the fuel assembly bowing condition of the EPR core is simulated and analyzed.The calculation results show that due to the change of local moderating effect,the small bending of fuel assembly has a relatively great influence on the core power distribution.When the maximum offset in the whole core problem is about 2mm,the relative change of the assembly power can reach about 5%.

关 键 词：组件弯曲 功率分布 蒙特卡罗程序 确定论程序 欧洲先进压水堆(EPR) 

分 类 号：TL327[核科学技术—核技术及应用]