一体化快堆的内增殖性能研究  

Study of Internal Breeding of Integral Fast Reactor

作　　者：霍兴凯 胡赟[1] 徐李[1] 杨勇[1] HUO Xingkai;HU Yun;XU Li;YANG Yong(Department of Nuclear Engineering Design,China Institute of Atomic Energy,Beijing 102413,China)

机构地区：[1]中国原子能科学研究院核工程设计研究所,北京102413

出　　处：《原子能科学技术》2023年第6期1111-1119,共9页Atomic Energy Science and Technology

摘　　要：为达到高燃耗、低后处理量、长换料周期,一体化快堆以高内增殖为设计方向。本文研究了棒径和P/D(栅距与棒径之比)两个主要堆芯设计参数与内增殖间的关系,研究了降低钠空泡反应性的措施对内增殖的影响。结果表明,棒径的增加和P/D的降低能够显著提高内增殖,为了降低钠空泡效应而增加上钠腔并降低堆芯高径比会造成内增殖的损失。棒径与P/D的具体取值应在物理与热工之间寻求平衡,而对钠空泡反应性应从反应堆整体安全设计上缓解,一体化快堆的设计应以内增殖性能和高效的闭式燃料循环为主要目标。To meet the requirements of mitigating the climate change,a large scale deployment of nuclear energy is expected,which impulses higher efficiency in the utilization of uranium resources.As one of the promising solutions,the integral fast reactor featuring in a high internal breeding can reach a high burn-up,low reprocessing mass,and a long refueling period.In this paper,the relationship between the breeding characteristics and two main design parameters of the core,the rod diameter and the pitch-to-diameter ratio(P/D),was studied.The negative impact on internal breeding caused by the measures for reduction of sodium void reactivity was also analyzed.All calculations were carried out with the Monte Carlo code RMC and ENDF/B-Ⅶ.1 continous-energy ACE data libraries.In each case the breeding characteristics were shown by both breeding ratio of the fissile nuclides and the regeneration ratio of the TRU nuclides.The variation of k eff,fissile nuclides,TRU nuclides along with burnup were also illustrated.The calculation results indicate that the internal breeding can be significantly enhanced by increasing the rod diameter and by decreasing the P/D.With the current U-Pu-10Zr fuel parameters,a satisfactory burnup reactivity curve can be realized with the rod diameter at 7.0 mm and the P/D at 1.14,taking into account a balance between neutronics and thermal-hydraulics.The positive sodium void reactivity effect makes one of the largest risks of sodium cooled fast reactor(SFR)under unprotected severe accidents.The sodium void reactivity effect can be reduced by setting an upper sodium plenum and reducing the core height-to-diameter ratio(H/D).However,both methods bring significant cost to the internal breeding,due to a higher leakage of neutrons under normal operation.In this paper it is found that to bring the whole-core sodium void reactivity down to zero,the H/D must be as low as 0.15 approximately under the existence of an upper sodium plenum at the height of 40 cm.Such a design results in a fast drop of the burnup re

关 键 词：钠冷快堆 金属燃料 一体化快堆 增殖 钠空泡反应性 

分 类 号：TL364.5[核科学技术—核技术及应用]