The operation of spacecraft life support systems is challenged in orbit by the microgravity environment. The near absence of buoyancy impacts the production and separation of oxygen and hydrogen by forcing the adoption of complex multiphase flow management technologies. Existing technical solutions lack the reliability and efficiency desired in long-term space missions, motivating the development of alternative systems. This paper presents a novel microgravity water-splitting architecture that avoids the use of water recirculation loops and primary ancillary equipment such as pumps or centrifuges. A magnetohydrodynamic electrolytic cell (henceforth, MHD drive) is employed to extract and separate oxygen and hydrogen gas by inducing a vortical flow within the cell volume. Ultimately, the adoption of this novel contactless actuation method avoids the adoption of moving parts and simplifies the operation of the system. The feasibility of implementing the MHD drive in a four-crew Mars transfer mission is assessed using a quasi-analytical multiphysics model validated at ZARM's drop tower. The mass, power consumption, and reliability of the system are compared with the ISS Oxygen Generator Assembly and NASA's Advanced Oxygen Generator Assembly. Early results indicate that the MHD drive provides up to 50% mass budget reductions with respect to the state of the art for a 99% reliability level thanks to its simplified system architecture and the consequent reduction in spare components.
Monfort-Castillo et al. (Sun,) studied this question.