Design of a Lithium Chloride Absorber Radiator for Flight Testing on an Extravehicular Mobility Unit

Thermal control systems for exploration space suits and spacecraft will need to meet critical requirements for water conservation and durability. Spacesuit Evaporator Absorber Radiator (SEAR) technology offers a non-venting thermal control approach. A SEAR system combines a lithium chloride absorber radiator (LCAR) with a spacesuit water membrane evaporator (SWME). To prove operation of a SEAR system in a space environment, we are currently designing and demonstrating a subscale SEAR system that is designed to meet requirements for a flight test as part of an EMU on the International Space Station. The flight-test system must meet critical requirements for safety, impact resistance, ease of use, durability/lifetime, and simplicity of operation. To meet these requirements, we have developed and demonstrated a new design for the LCAR housing that increases durability dramatically compared to prior prototypes. We have also developed new concepts for integrating the LCAR with the EMU that use existing spacesuit interface components. The overall SEAR system includes controls that will enable operation during EVA with minimal direct intervention by the crew. We have formulated plans for controlling water chemistry to prevent corrosion and growth of microbes in the system. Finally, we have developed a concept for regenerating the LCAR on orbit using existing ISS experimental accommodations. The regeneration system will enable multiple absorption/regeneration cycles while on orbit while also demonstrating critical features of SEAR operation in microgravity.