【摘要】 通过数值分析手段，从中子物理角度对微型核反应堆（微维）常用的冷却剂/慢化剂材料进行了比较。以六边形结构设计堆芯、金属铍为反射层，采用MCNP软件建模计算了不同冷却剂/慢化剂下堆芯的临界特性、栅元轴向功率分布、堆芯径向功率分布、中子能谱、反应性控制等，比较了其中子物理特性。结果表明：在慢化剂与燃料的比值较小时，水慢化性能最佳，三联苯的过慢化特性不明显，氢化锆的慢化能力为三者最低。三种工质满足最基本的安全性要求，但是水作为高富集度微堆燃料的冷却剂不适合。更多还原

【Abstract】 This study compares the commonly used coolants/moderators for micro-nuclear reactors from the perspective of neutron physics through theoretical analysis. The core was constructed in hexagonal and metal beryllium was set as the reflector. The critical characteristics of the core under different coolants/moderators, axial power distribution of the cell, radial power distribution of core, neutron energy spectrum, and reactive control were calculated by the model achieved from MCNP, and those physical characteristics were compared. Results indicate that water has the best moderating performance, when the ratio of moderator to fuel is small. Under the same conditions, the overmoderated characteristic of terphenyl is not obvious, and the moderation capacity of ZrH is the lowest. All working fluids meet the basic safety requirements, but water is not suitable for coolant used in high-enrichment fuels.更多还原