Preliminary modeling evaluation of water ice extraction from lunar permanently shadowed craters by direct heating of icy regolith

Abstract

This work sets the foundation for preliminary modeling of water ice extraction from lunar permanently shadowed craters. Analysis of the research results indicates that (1) favorable phase changes at low temperatures and pressures (though not in-situ conditions) occur and lead to the upward migration of water vapor through the regolith and out of the crater surface, (2) the appearance of the liquid phase significantly reduces the timesteps in the simulation and limits predictive modeling capabilities, (3) adjusting the reservoir model to true lunar conditions requires specific modification of the Fortran base code of TOUGH+, (4) the lack of a void-like phase prevents realistic modeling of mass and energy balance in lunar permanently shadowed craters, (5) a stepwise heat source may yield greater water production for deeper ice reservoirs than a single heat element. The reservoir simulation investigated phase saturation changes of water iced buried in lunar regolith over a three-day period from a 25 W continuous heat source.