of Atmospheric Water on Mars in Support of the NASA Mars Reference Mission
M. R. Grover and A. P. Bruckner
Department of Aeronautics and Astronautics, University of Washington
The University of Washington has designed an in situ resource utilization system to provide water to the life support system in the laboratory module of the NASA Mars Reference Mission, a piloted mission to Mars. This system, the Water Vapor Adsorption Reactor (WAVAR), extracts water vapor from the Martian atmosphere by adsorption in a bed of type 3A zeolite molecular sieve. Using ambient winds and fan power to move atmosphere, the WAVAR adsorbs the water vapor until the zeolite 3A bed is nearly saturated and then heats the bed within a sealed chamber by microwave radiation to drive off water for collection. The water vapor flows to a condenser where it freezes and is later liquefied for use in the life support system. In the NASA Reference Mission, water, methane, and oxygen are produced for life support and propulsion via the Sabatier/Electrolysis process from seed hydrogen brought from Earth and Martian atmospheric carbon dioxide. In order for the WAVAR system to be compatible with the NASA Reference Mission, its mass must be less than that of the seed hydrogen and cryogenic tanks apportioned for life support in the Sabatier/Electrolysis process. The WAVAR system is designed for atmospheric conditions observed by the Viking missions, which measured an average global atmospheric water vapor concentration of ~2x10^-6 kg/m3. WAVAR performance is analyzed taking into consideration hourly and daily fluctuations in Martian ambient temperature and wind speed and the corresponding effects on zeolite performance.