Research on Development of Burnup Library for PWR

燃耗数据库的精准性是影响燃耗计算结果精准性的主要因素。本文开发了燃耗库加工程序PSTL，并基于评价核数据库ENDF/B-VIII.0、EAF-2010和TENDL-2019制作了一个用于ORIGEN-S程序的压水堆燃耗数据库。该数据库包含两个子库：中子截面-裂变产额库和衰变库。中子截面数据首先应用NJOY2016程序将ENDF/B-VIII.0等评价库中的点连续截面处理为172群截面，然后采用指定燃耗深度下的组件或栅元中子能谱将172群截面并为三群截面；裂变产额数据取自MF8/MT454和MT459；衰变数据取自MF8/MT457。最后采用OECD/NEA机构的压水堆核素积存量基准题进行验证分析，结果表明：中子能谱对燃耗库以及核素积存量有显著影响，对于238Pu、237Np和147Sm等核素，由组件中子能谱所加工的燃耗库的计算结果更接近实验值，提高了ORIGEN-S的计算精度。The accuracy of burnup library is the main factor affecting the accuracy of burnup calculation results. In this paper, the library processing program PSTL is developed, and a PWR burnup library for ORIGEN-S program is made based on the evaluated nuclear libraries ENDF/B-VIII.0, EAF-2010 and TENDL-2019. The library contains two sublibraries, namely neutron cross section-fission yield library and decay library. First, the point continuous cross sections in ENDF/B-VIII.0 evaluated library and so on are processed into 172-group cross sections by NJOY2016 program. Then the 172-group cross section is further merged into three-group cross sections by using the neutron spectrum of the assembly or cell at the specified burnup depth. Fission yield data are taken from MF8/MT454 and MT459. Decay data are taken from MF8/MT457. Finally, the benchmark of nuclide inventory in PWR of OECD/NEA is used to verify and analyze. The results show that the neutron energy spectrum has a significant effect on burnup library and nuclide inventory. For such nuclides as 238Pu, 237Np and 147Sm, the calculated results of the burnup library processed by the assembly neutron spectrum are closer to the experimental values, which improves the calculation accuracy of ORIGEN-S.