Establishing a lunar base is the first step for human space exploration, and providing stable and reliable energy for the base is one of the most critical priorities. Compared to solar energy, nuclear power offers advantages such as high power output, low mass-to-power ratio, long operational lifespan, and all-weather power supply, making it an ideal energy solution for lunar surface bases.

This study aims to design a lunar surface heat pipe molten-salt reactor with a 20-a lifetime to meet the 100 kWe electrical power requirement, capable of generating power immediately after landing on the lunar surface without additional shielding.

First of all, the structure and main parameters of Lunar surface Heat Pipe Molten Salt Reactor (LHPMSR) were determined according to design requirement. Then, the neutron physics and shielding analysis were conducted using SCALE 6.1 to obtain the radial distribution of neutron flux, power distribution, variation of k_eff during reactor's lifetime and radiation dose distribution, and select the Al₂O₃ as the reflective layer material where the reactivity control was achieved by controlling the rotation of the drum. After calculating the viscous limit, sonic limit, entrainment limit, boiling limit, and capillary limit of the heat pipe, an analysis of its heat transfer limits was conducted. Finally, the heat pipe thermal transfer was simulated through thermal resistance network methodology, and thermal-hydraulic analysis was performed using coupled Computational Fluid Dynamics (CFD) approach to obtain temperature distributions of reactor core and the heat pipe, as well as the molten salt velocity distribution.

Analytical results indicate that the three-zone core configuration effectively achieves power flattening and full-power operation for 20 a is maintained without requiring additional shielding or refueling. Meanwhile, the heat pipe thermal transfer capacity remains below critical heat flux limits, meeting design specifications.

The overall design satisfies the preliminary construction requirements for lunar bases and provides valuable references for molten salt reactor designs on planetary surfaces.