A calculation method of a heat rejection system in a lunar power plant consisting of a free-piston Stirling engine (FPSE)

The colonization of the Moon and building permanent lunar outposts in the near future has become a main objective for most space agencies around the world. Future lunar outpost with a permanent human presence would have high power requirements to support such activities as scientific experimentation, in situ mining and processing, astronomical observation, and surface exploration. Several challenges are associated with the habitation of the lunar surface, such as, choosing an appropriate power generation unit. Stirling engines are one of the attractive power generation options which were implemented in space missions before, and are most likely to be used in future space exploration missions. In this paper, a detailed calculation methodology of a radiator design in a lunar power plant is developed. A brief research on some of the challenges that are associated with the habitation of the Moon and an overview of a lunar power plant consisting of a free piston Stirling engine (FPSE) are presented. A program code based on the developed calculation methodology consisting of two algorithms (one- and two-dimensional cases) was developed, and the results of both algorithms were compared and presented. Moreover, three different radiator design options having helium as a refrigerant circulating in them were considered and their results were analyzed. Finally, the conclusions and future directions of this work are provided. •Stirling engines are an effective power generation option on the moon.•Solar and Nuclear power should be considered as an energy source on the moon.•A suitable location on the moon should have stable temperature ranges.•Thermophysical properties of the refrigerant affects the work of the radiator.•Hydraulic resistance in the pipes affects the dimensions of the radiator.