热管堆在不同基体材料下的燃耗特性分析

Depletion calculation of heat pipe cooled nuclear reactor with different monolithic materials

热管冷却核反应堆具有非能动传热、模块化和固有安全性高等特点,在航空探索、深海作业和偏远地区电力市场上有广泛的应用。以洛斯阿拉莫斯国家实验室开发的5 MWth热管堆为研究对象,选择SS-316,Mo-14Re和SiC作为基体候选材料,采用反应堆蒙特卡罗中子输运分析程序对比分析了以上三种基体堆芯的反应性、中子能谱、增殖性能和燃耗演化。结果表明:为了维持堆芯的10年运行,SS-316,Mo-14Re和SiC三种基体堆芯所需的初始燃料235U富集度分别约为19.35%,28.80%和17.10%,SiC基体堆芯所需的初始燃料235U富集度最小;10年后,SiC基体堆芯产生的易裂变核素(239Pu和241Pu)和次锕系核素(通过分离嬗变可被再次利用)的量最高,分别约为11.91 kg和92.08 g。综合以上研究结果,推荐SiC作为热管冷却核反应堆的基体。

Heat pipe cooled nuclear reactor has unique advantages,such as passive heat transfer technology,modular design and inherent safety.It has been extensively used in deep space,deep sea and decentralized electricity markets.Recently,Los Alamos National Laboratory designed a 5 MWth heat pipe cooled nuclear reactor for decentralized electricity markets.This paper aimed to provide an appropriate reference for the choice of types of monolithic core in the engineering design of heat pipe cooled nuclear reactor.With the help of a Monte Carlo simulation program RMC,reactivity,neutron spectrum,breeding performance and burnup evolution were explored on the heat pipe cooled nuclear reactor with monolith materials SS-316,SiC and Mo-14Re,respectively.The results show the reactor with monolith materials SS-316,Mo-14Re and SiC can achieve a 10-year operation when the enrichment of the initially loaded 235U is about 19.35%,28.80%and 17.10%,respectively.The SiC monolith core requires the least initial 235U enrichment.Besides,the core with SiC monolith can produce the highest mass of fissile 239Pu and 241Pu(about 11.91 kg)and minor actinides(about 92.08 g)for a 10-year operation.Thus,SiC monolith is recommended for the pipe cooled nuclear reactor.