基于数值积分的核截面在线生成方法研究  

On-the-fly nuclear cross section generation based on numerical integral method

作　　者：陈锐[1,2] 周书民[2] CHEN Rui;ZHOU Shumin(Jiangxi Engineering Research Center of Process and Equipment for New Energy East China University of Technology,Nanchang 330013,China;Engineering Research Center for Nuclear Technology Application,Ministry of Education East China University of Technology,Nanchang 330013,China)

机构地区：[1]东华理工大学江西省新能源工艺及装备工程技术研究中心,南昌330013 [2]东华理工大学核技术应用教育部工程研究中心,南昌330013

出　　处：《核技术》2018年第12期78-82,共5页Nuclear Techniques

基　　金：国家重大科学研究计划项目(No.2017YFF0104200);国家自然科学基金(No.11565002);江西省教育厅计划项目(No.GJJ150558);江西省新能源工艺与装备工程技术研究中心开放基金(No.JXNE2017-04);教育部工程研究中心开放基金(No.HJSJYB2017-2)资助~~

摘　　要：为准确模拟反应堆内不同温度下中子与各种材料间的相互作用,当反应堆堆芯温度变化时,需要在线生成不同温度下的反应截面。现有在线截面生成方法中,以MCNP6的曲线拟合法使用较为普遍,但该方法的截面生成效率偏低。为此,本文开展了基于数值积分的核截面在线生成方法研究,结合双指数变换与GaussHermite积分替代原有解析积分,提高展宽截面生成效率。典型核素与多普勒反应性系数基准例题结果显示,数值积分方法的曲线拟合计算效率比原始方法平均高10倍以上,且精度与原始方法相对偏差在1.54%以内,验证了本文方法的有效性,可用于反应堆多物理耦合计算。[Background]When the reactor core temperature changes,the reaction cross sections at different temperatures need to be generated with on-the-fly methods.Among the existing on-the-fly cross-section generation methods,the curve fitting method is becoming a common tool used in MCNP6,but the efficiency of this method is quite low.[Purpose]This study aims to accurately simulate the interaction between neutrons and various materials at different temperatures in the reactor by developing an on-the-fly generation method of nuclear cross sections. [Methods]In order to overcome the low efficiency of Doppler broadening in the parameter fitting method of MCNP6, double exponential method and Gauss-Hermite method are combined to replace the original analytical integral method to increase the width of the cross section generate efficiency.[Results]The typical nuclides test results showed that the curve fitting calculation efficiency of the numerical integration method is more than 10 times higher than the original one.Doppler reactivity coefficient benchmark example shows that the curve fitting of the numerical integration method is relative to the accuracy of the original method within 1.54%.[Conclusion]This method can beused for multi-physics coupling calculation of reactors.

关 键 词：中子截面 数值积分 在线 多普勒展宽 

分 类 号：TL329.2[核科学技术—核技术及应用]