摘要
球床氟盐冷却高温反应堆作为第四代反应堆,选用2LiF-BeF2做冷却剂。2LiF-BeF2中含有微观吸收截面很大6Li核素,其摩尔含量会对冷却剂的温度反应性系数造成影响,因此研究6Li摩尔含量对冷却剂温度反应性系数的影响十分必要。本文以无限球床为计算模型,利用SCALE6(Standardized Computer Analyses for Licensing Evaluation)对不同6Li摩尔含量的冷却剂温度反应性系数进行研究。分析结果表明,当冷却剂中6Li摩尔含量占Li元素总量的0.005%时,冷却剂中6Li和7Li的宏观吸收截面大致相当;随着6Li摩尔含量的增大,冷却剂的温度反应性系数由负向正转变,并逐渐增大;基于四因子公式的分析表明,引起冷却剂的温度反应性系数由负变正的主要因素为热中子利用系数的变化。
Background： The 6Li in the coolant 2LiF-BeF2 of Fluoride-Salt-Cooled High Temperature Reactors, one type of generation IV, has a large microscopic thermal neutron absorption cross section. Purpose： The impact of 6Li concentration on the coolant temperature reactivity coefficient of Fluoride-Salt-Cooled High Temperature Reactors is reached. Methods： The coolant temperature reactivity coefficient was performed for Fluoride-Salt-Cooled High Temperature Reactors with different 6Li molar compositions of 2LiF-BeF2 as coolants by using the computer codes KENO in SCALE6（Standardized Computer Analyses for Licensing Evaluation）. Results： The neutron absorptive capability of 6Li in the coolant equals to that of 7Li when the 6Li mole content is 0.005%. The results are given that the coolant temperature reactivity coefficient is changing from negative value to positive value with increasing of the 6Li molar compositions of 2LiF-BeF2. Conclusion： Based on the analysis of the four factor formula, it can be concluded that the change of the thermal utilization coefficient mainly accounts for the increase of coolant temperature coefficient of reactivity.
出处
《核技术》
CAS
CSCD
北大核心
2014年第9期69-75,共7页
Nuclear Techniques
基金
中国科学院战略性先导科技项目(No.XDA0201002)
上海市科学技术委员会项目(No.11JC1414900)
国家重点基础研究发展计划(No.2010CB934501)
国家自然科学基金(No.11005148)资助
关键词
无限球床
6Li摩尔含量
宏观吸收截面
四因子
温度反应性系数
Infinite bed, 6Li molar compositions, Macroscopic absorption cross section ∑a, Four factors, Coolanttemperature reactivity coefficient
