Joint Study on Reactor Physics of Next Generation Reactors

根据法国原子能能源委员会和代表日本大学协会的京都大学研究反应堆研究所之间的协议，1993年开始了一项合作研究，以促进下一代轻水反应堆的物理学研究和发展。请注意，该协定于1996年延长至1999年。选取了混合氧化物（MOX）燃料电池反应性的空隙系数、重叠共振存在时的自屏蔽效应、混合燃料（MOX和UO_2）组件的引脚功率分布、MOX和UO_2燃料电池反应性的慢化温度系数以及燃料消耗（包括钚燃烧和少量锕系元素（MAs）的变化）等基准计算作为待解决的问题。CEA与大学协会的联合研讨会每年轮流在法国和日本举行，讨论双方的计算结果。计算结果的差异主要来自于包括钚同位素在内的一些核数据的差异。对于第1项和第4项，将向科学期刊提交共同论文，并决定增加有关MOX燃料电池敏感性分析的新项目。对于项目2)，将通过基准计算强调各自开发的方法之间的差异。项目(3)推迟审议。项目5)采用本研究中MOX燃料的耗竭基准作为OECD/NEA基准。双方将对日本压水堆燃料辐照后实验进行分析，并在法国辐照实验的基础上制定新的MAs耗尽基准。此外，还将研究中子泄漏效应在电池计算中的处理。

Under the agreement between the Commissarial l'Energie Atomique (CEA) of France and Kyoto University Research Reactor Institute (KURRI) on behalf of the University Association in Japan, a cooperative study has been initiated in 1993 to promote the research and development on the physics of light-water reactors of next generation. Note that this agreement was extended in 1996 until 1999.Benchmark calculations on 1) the void coefficient of reactivity in mixed-oxide (MOX) fueled cells, 2) the self-shielding effect in the presence of overlapping resonances, 3) the pin power distribution in a mixed fuel (MOX and UO_2) assembly, 4) the moderator temperature coefficient of reactivity in MOX and UO_2 fueled cells, and 5) the fuel depletion which includes plutonium burning and minor actinides (MAs) transmutation were selected as problems to be solved. The joint seminar between CEA and the University Association was held alternately in France and Japan every year to discuss the calculated results of the both sides.It was found that differences between the calculated results mainly came from differences in some nuclear data including plutonium isotopes. For the items 1) and 4), common papers will be submitted to a scientific journal, and it was agreed to move in a new item concerning the sensitivity analysis on MOX fueled cells. For the item 2), differences between the methodologies individually developed will be underlined through benchmark calculations. The item 3) was postponed. For the item 5), the depletion benchmark of MOX fuel in this study was adopted as an OECD/NEA benchmark. The both parties will perform analyzes on the post irradiation experiment of Japanese PWR fuel, and a new depletion benchmark of MAs will be prepared on the basis of the French irradiation experiments. In addition, the treatment of the neutron leakage effect in cell calculation will be investigated.