NHR-10堆芯的改进设计

Improved NHR-10 core design

介绍了 NHR- 10组件内钆可燃毒物配置、堆芯燃料组件布置和换料方案的改进设计。通过调整钆可燃毒物根数和质量分数来改善堆芯有效增殖因子 (Keff)随燃耗变化的特性 ,采用堆芯燃料组件非均匀布置来降低堆芯功率峰因子(Fxyz) ,采用 1/ 2换料方案使得每炉换料周期比较接近 ,并给出了改进设计结果。TRANP和 NNGFM程序计算结果表明 :改进设计后 ,Fxyz从 2 .997降到 2 .2 2 1,运行中的最大Keff从 1.0 5 6降到 1.0 37,Keff随燃耗的变化特性得到了很大改善 ,换料周期除第一个周期为 2 2 5 0 d外 ,后面的周期稳定在 175 0 d,更加符合工程需要。

This paper introduces the improved NHR 10 core design which includes the arrangement of the gadolinium burnable poison (BP), the fuel assembly arrangement and the fuel assembly reloading scheme. The number and the mass percent of gadolinium BP were adjusted to improve the characteristics of K eff versus the fuel burnup. A heterogeneous fuel assembly arrangement was used to decrease the power peaking factor. A 1/2 reloading scheme was used to decrease the differences between reload cycles. The improved design, analyzed with the TRANP and NNGFM codes, reduced the power peaking factor from 2.997 to 2.221 and the maximum K eff during operation from 1.056 to 1.037 with improvcments of the characteristic K eff versus the fuel burnup. The reload cycles are 1750 days long except for the first cycle which is 2250 days long, both of which are more suitable for engineering needs.