Mars Transfer Vehicle (MTV) Water Processor Analysis 2008-01-2193

This paper considers the design of a Mars Transfer Vehicle (MTV) water processor. The Constellation Program has begun to consider the first human mission to Mars, and the MTV water processor is of special interest. Mars transit system design is not affected by Extra-Vehicular Activity (EVA) or In-Situ Resource utilization (ISRU). The total duration of Mars transit and return is relatively fixed at about four hundred days, while Mars and lunar surface stays can vary from a few days to many years. The Mars transit water processor will operate in zero gravity, like the International Space Station (ISS) Water Recovery System (WRS), so the ISS WRS design can serve as a reference baseline for the Mars transit system. The paper develops the MTV water requirements and considers the suitability of the ISS WRS for Mars transit. The ISS WRS meets MTV requirements and requires less mass than direct resupply for Mars transfer, but it has excess capacity for the requirements. The water processor should be redesigned to meet MTV requirements, reduce mass and logistics, improve reliability, and take advantage of lessons learned and technology advancements. The MTV water balance, potential loop architectures, and candidate processor technologies are discussed.