超临界水堆燃料组件内的排列研究

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.

Study on the layout of the SCWR fuel assembly

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 th...