Safe, Non-Corrosive Dielectric Fluid for Stagnating Radiator Thermal Control System

Paragon proposes to develop a single-loop, non-toxic, stagnating active pumped loop thermal control design for NASA's Orion or Lunar Surface Access Module (LSAM) program. While this technology was developed in the Apollo era, it has not been used in space since then. Furthermore, the fluids used in those first-generation units are not compatible with today's human-rated flight requirements as they could be considered toxic and/or flammable. Though work at JSC by Tuan et al. has targeted modeling and verifying the model of a stagnating radiator with one candidate fluid, Paragon proposes to parallel this effort with an alternative fluid as a back-up to that currently base-lined in the Orion program. This technology will be a significant innovation in that stagnating radiator designs provide self regulation of thermal dissipation parameters. As heat flow to the radiator is reduced, less cooling capacity is required; stagnating radiators incorporate fluids that gradually change properties. If increased heating loads are encountered, the radiator working fluid changes again to increase the heat transfer capability of the radiator. This technology is directly relevant to NASA's Orion and LSAM development. Our plan for Phase I and II is in-line with bringing this technology from a TRL 2 to a TRL 4-6 depending on Phase II assumptions.