超临界水堆燃料组件内的排列研究  

Study on the layout of the SCWR fuel assembly

作　　者：秦冬[1] 常华健[1] 

机构地区：[1]清华大学核能与新能源技术研究院,北京100084

出　　处：《核科学与工程》2009年第1期56-61,共6页Nuclear Science and Engineering

摘　　要：超临界水冷反应堆(SCWR)是第四代核能系统国际论坛(GIF)推荐的六种堆型中唯一的轻水堆型。SCWR和现有的轻水堆相比,具有热效率高,系统设备大大简化的优点。世界范围内的研究纷纷展开,其中燃料组件的设计优化及堆芯布置是一个重要的研究方向。本文分析比较了当前比较流行的几种燃料组件设计,在采用同一富集度燃料且不含可燃毒物的情况下,利用MCNP程序对这几种组件的当地功率峰值因子进行了计算,发现其离设计目标还有一段距离。本文分析了影响当地功率峰值因子的若干因素,发现对于正方形组件,在均匀慢化、降低当地功率峰值因子的同时也使得组件整体上慢化不足,表现为倍增因子降低,这主要与燃料棒的排列方式有关。通过对比分析发现,相对于正方形排列,改进过的六角形排列更容易解决充分慢化和均匀慢化之间的矛盾,实现组件设计的优化。The supercritical water reactor （SCWR） is the only light water reactor of the six reactor types recommended by the Generation IV International Forum （GIF）. Compared with traditional LWR, SCWR may achieve high thermal efficiency and simple plant equipment. Related researches are being carried out worldwide, among which the optimal design for fuel assembly and core is an important trend. This paper analyzes the current fuel assembly （FA） designs and calculates their local power peaking factors with MCNP code under the condition of using the same enrichment fuel and containing no burnable poison, and finds that the local power peaking factors of these FAs are a little far away from the design objective. This paper analyzes several factors influencing local power peaking factor, and shows that in the case of uniform moderation, the square FA depress local power peaking factor with the disadvantage of making the fuel assembly under-moderation as a whole and decrease consequently the Keff, which is mainly caused by the arrangement of the fuel rods. The paper also comes to a conclusion that, compared to the square FA, the hexagonal FA will easily resolve the contradiction between the uniform moderation and full moderation, achieving the optimization of the fuel assembly design.

关 键 词：超临界水冷堆 燃料组件 当地功率峰值因子 

分 类 号：TL34[核科学技术—核技术及应用]