Development and Projected Capabilities of Chamber D

Chamber D is a Thermal-Vacuum (TVAC) chamber that is currently being developed by the National Aeronautics and Space Administration (NASA) Johnson Space Center (JSC) Crew and Thermal Systems Division (CTSD) to simulate the environment of a lunar Permanently Shadowed Region (PSR). A gaseous helium cooled shroud is being integrated into a vacuum chamber. Chamber D is in the Space Environment Simulation Laboratory (SESL) which includes the large TVAC chambers, Chamber A and Chamber B. A liquid nitrogen thermosiphon and a helium refrigeration system are used to control the temperature of the Chamber A shrouds. Chamber A and Chamber B also use helium refrigeration to create the final high vacuum levels. In total, the SESL has a large helium refrigeration system (12.5 KW) to create the thermal environment in Chamber A and also has a separate smaller refrigeration system (3.5 KW) for cryopumping in both chambers. The smaller system that cools the cryopumping panels in Chamber A and Chamber B is being used to cool the gaseous helium-cooled shroud of Chamber D. As a result, Chamber D will have a significant refrigeration capacity relative to TVAC chambers of similar size. The development and projected capabilities of Chamber D will be discussed.