An experiment was designed, fabricated and tested at the NASA Lewis Research Center to investigate the concept of using the surface layer of the moon to store thermal energy. The concept includes using the energy stored within the surface as a thermal input to drive a solar dynamic power system. The solar dynamic power system would operate using the suns thermal input during the lunar day and would continue to operate during the lunar night using the thermal energy stored within the cavity.
The experiment modeled in a lunar thermal energy storage concept by applying a heat flux to the surface of simulated lunar soil equivalent to what a primary and secondary solar concentrator could produce with a concentration ratio of 2000:1.
The experiment was designed to determine if the surface layer of the lunar soil could be melted using the equivalent heat flux from a radiative heating element mounted above the simulated lunar soil. If a melt occurred, the melt characteristic including the formation shape and amount of the soil melted was to be evaluated. Other objectives of the experiment included studying the effects of re-melting the soil after the molten cavity solidifies, and generating a temperature profile throughout the soil as the heat cycle was applied.
The experiment successfully generated a cavity within the surface layer of the simulated soil. This report describes the experiment in detail and highlights the results. It demonstrates the feasibility of melting the lunar soil with a solar concentrator. These results are the first step towards developing a lunar solar dynamics system which stores thermal energy in the surface layer of the lunar soil.