中文摘要：

针对新型的采用无铍熔盐燃料的氧化铍慢化钍基熔盐堆,利用上海核工程研究设计院自主开发的SONG/TANG-MSR程序系统,通过大量的方案分析,在熔盐堆栅格尺寸、P/D（栅距与燃料孔道直径的比值）、233 U含量等关键栅格参数上对钍基熔盐堆进行优化。计算结果表明,采用较低的233 U浓度的小栅距栅格设计,新型的熔盐堆设计具有很高的增殖比,并保持负功率系数。与传统熔盐堆相比,新型钍基熔盐堆具有更高的核燃料增殖能力。经过栅格优化的新型钍基熔盐堆可满足下一代核能系统可持续性和安全性要求。

英文摘要：

Based on an advanced concept of thorium molten salt reactor（TMSR）which applied a fuel composition without BeF2 and solid BeO moderator,key lattice parameters including lattice dimensions,P/D（ratio of lattice pitch to channel diameter）and 233 U content were optimized through varies scheme analyses.SONG/TANG-MSR,an inhouse developed computer code system,was employed in the optimal design of TMSR.Adopting a small pitch size and rather low 233 U content,an advanced TMSR achieved a high breeding ratio and maintained a negative power coefficient as well according to computation results.Compared with traditional MSR,the advanced TMSR is better in breeding nuclear fuel.With these lattice parameters,the advanced TMSR meets the requirements of next generation nuclear power systems on safety and sustainability.