针对40 kWe热管型月球堆的辐射屏蔽问题，建立了三维蒙特卡罗计算模型。屏蔽布局方式整体采用地埋式，堆芯上方的轴向屏蔽体则采用影锥构形，选取适用温度范围宽、耐辐照的碳化硼作为中子屏蔽材料，伽玛屏蔽材料则采用钨，模拟计算了空腔及钨层厚度对轴向屏蔽体后端典型位置的辐射影响，同时也考察了百米外人员所受剂量随径向屏蔽体厚度的变化关系。据此得到了热管型月球堆初步的屏蔽体构型，其总质量为2�15 t ，十年运行寿期内紧靠屏蔽体后端的敏感器件最大中子注量（1 MeV等效）为1�86×1014 cm－2、最大伽玛剂量为3�68 Mrad，而人员剂量仅为11�92 mSv／a，在较大的裕量范围内满足辐射安全要求。%Three⁃dimension Monte Carlo calculation model was built to study the radiation shielding of heat pipe cooled lunar surface reactor with 40kWe. The lunar soil buried shielding method was chosen for the overall layout and the cone⁃shadow configuration was adopted for the axis shielding. B4 C was used for neutron shielding owing to its large range of applicable temperature and high radia⁃tion resistant, and W was adopted for gamma shielding. The radiation fluence on the back end of the axis shielding versus the chamber and W’ s thickness were calculated. The dose for an astronaut 100 m away versus the radial shield thickness was also calculated. The primary shielding configuration was provided and the whole mass was 2�15 t. The maximal neutron fluence (1 MeV equivalent) was 1�86 × 1014 cm-2 and the maximal gama dose for the radiation sensitive component was 3. 68Mrad, dose for an astronaut 100 m away was only 11�92 mSv/a. The shield design can satisfy the shielding requirements with a large margin.
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