Thermal, mass and momentum transport phenomena as a necessary step to process wastes during long duration space missions by supercritical water oxidation

Abstract

One of the challenges associated with future long duration planetary missions is supplying with essential resources in a closed-loop life support system. For this purpose, a deep understanding of the thermodynamic and transport properties of near and supercritical fluids is required. The most important results concerning thermal, mass, and momentum transport which were obtained since nearly 40 years are reviewed in this aspect. The results also include the effect of vibrations on the liquid-vapor interface position and the onset of specific vibrational instabilities. Major results are concerned with the discovery of thermal behavior specific to near-critical fluids (Piston Effect, boiling), universality of phase change evolution and specific vibrational instabilities. These findings are applied to the studies concerning the use of supercritical waste oxidation in space weightlessness, a promising technology for efficiently and safely disposing wastes. Although this technology is not in its final state and needs further developments, such investigations offer valuable openings to identify potential hazards, improve system design and develop safety protocols for all supercritical fluids ground applications.