【摘要】 为对核废物进行嬗变,最近提出了加速器驱动的次临界系统(Accelerator Driven System,简称ADS)。由于外中子源的存在及中子通量的各向异性,ADS的核计算与通常反应堆有较大的差别,原则上需要应用中子输运理论的方法,目前尚无成熟的计算方法与程序。为此,IAEA提出了ADS基准题。基准题分为几个阶段,第一阶段主要致力于ADS的中子性能分析、检验现有核数据库、计算方法和程序的可靠性及不确定性。该文开发了MCNP-ORIGEN2程序系统,并对该基准题进行了给定次临界度下的富集度、零燃耗下的径向与轴向的功率分布、反应性空泡效应、外源价值和燃耗的计算等,取得了满意的结果。更多还原

【Abstract】 Recently for transmutation of spent nuclear fuel, the Accelerator Driven System is introduced. Because of anisotropic flux distribution caused by source, the nuclear calculation of ADS is significantly different from the normal nuclear reactor. It is necessary to apply the transport theory method. IAEA issued an ADS benchmark. It is divided into several stages, and the 1st stage devoted to analyzing neutron performances of ADS and validating the nuclear databases and the codes used for computation of ADS. In this paper, a transport and depletion code system MCNP-ORIGEN2 is developed. Initial enrichment of 233U which corresponds to given initial (BOL)Keffvalues are calculated. And then,the spatial distributions of power density (BOL), the void reactivity effects, the spallation source effectiveness ψ* , and the evolution curves of Keff and sourceas Sanction of time are also calculated for every given Keff(BOL). The numerical results are in a good agreement with those of various countries.更多还原