基于快谱基准题的TULIP程序适用性研究与验证  

Applicability and validation of TULIP code based on fast spectrum benchmarks

作　　者：陈文杰 杜夏楠 王茸 郑友琦[1] 王永平[1] 吴宏春[1] CHEN Wenjie;DU Xianan;WANG Rong;ZHENG Youqi;WANG Yongping;WU Hongchun(School 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学院,西安710049

出　　处：《核技术》2023年第12期141-150,共10页Nuclear Techniques

基　　金：国家自然科学基金(No.12005160)资助。

摘　　要：NECP-SARAX是西安交通大学核工程计算物理实验室开发的先进反应堆中子学分析系统,近些年基于CEFR、PHENIX、SUPERPHENIX、JOYO MK-I、ZPR和ZPPR等反应堆开展了程序的验证与确认工作,计算结果表明:NECP-SARAX在快堆堆芯物理特性分析具有良好的性能。同时,利用上述反应堆中的燃料组件和控制棒组件,初步展现了截面计算程序TULIP在快谱问题计算分析上的精确性,但是仍然缺乏系统性地验证与确认。为了确认TULIP程序对于不同类型快谱问题的适用性,从国际临界安全基准评估项目中选取了147组临界实验装置进行计算分析,发现对于带有厚反射层的实验装置,TULIP程序计算k_(eff)和蒙特卡罗程序计算值的偏差超过10^(-2)。以HMF021-002实验装置构造均匀两核素问题展开研究,中等质量核素在非共振区表现出类似共振波动状的散射截面,对于使用大量结构材料的快谱系统,其非共振区类似共振波动截面的自屏效应变得不可忽略。针对此现象,对TULIP程序的共振计算策略和非共振区计算方法进行优化,采用超细群(Ultra Fine Group,UFG)的共振计算方法,对中等质量核素高装载量情况下非共振区类似共振波动状截面的自屏效应进行处理,改进程序后相应实验装置计算偏差降低到3×10^(-3)内,数值结果表明,改进后的TULIP程序对于快谱系统具有良好的计算分析能力。[Background]NECP-SARAX is a neutronics analysis code system for advanced reactors developed by the Nuclear Engineering Computational Physics Laboratory team of Xi'an Jiaotong University.In the past few years,a considerable amount of verification and validation work has been done based on CEFR,PHENIX,SUPERPHENIX,JOYO MK-I,ZPR,and ZPPR reactors.The results indicate that NECP-SARAX offers high performance for fast spectrum reactor analysis.Meanwhile,the fuel and control rod assemblies of these reactors are used for verification of the cross-section generation code TULIP.While TULIP has demonstrated promising preliminary results in fast spectrum system analysis,a comprehensive systematic verification and validation process remains essential.[Purpose]This study aims to validate the applicability of TULIP code for various fast spectrum systems.[Method]Firstly,a total of 147 critical experiment benchmarks were selected from ICSBEP and used for analysis.The initial results demonstrated that the keff bias between TULIP and Monte Carlo codes exceeded 10^(-2) for an experimental benchmark with a thick reflector.Then,a homogeneous two-nuclide problem simplified from the HMF021-002 benchmark was subsequently used to analyze this phenomenon,and the intermediate-weight nuclides had resonance-like fluctuating scattering cross sections above the resonance energy.Finally,to address this phenomenon,the TULIP code was undergone enhancements,mainly focusing on optimizing the resonance calculation strategy and method using ultra fine group to deal with thee self-shielding effect of resonance-like cross sections in the non resonant region under high loading of intermediate-weight nuclides.[Results]In a fast spectrum system with a large amount of structural material,the self-shielding effect of the resonance-like cross section of the intermediate-weight nuclides above the resonance range becomes non-negligible.The optimized TULIP method reduces the keff bias to within 3×10^(-3) for these benchmarks with a thick reflector.[Conclusions]N

关 键 词：TULIP程序 ICSBEP基准题 中等质量核素 非共振区 类似共振状的截面 

分 类 号：TL942[核科学技术—辐射防护及环境保护]