Development and Testing of the Advanced Lightweight Radiator Development Unit (ALRDU)

The Advanced Lightweight Radiator Development Unit (ALRDU) is a composite radiator panel built for the Advanced Thermal Exploration Technology Development Project. As a point of reference, the ALRDU is sized to meet the requirements captured during an early design iteration of the Crew Exploration Vehicle (CEV). The composite radiator panel development included an evaluation of various tubing and composite panel attachment methods previously performed at NASA Glenn Research Center (GRC). The resulting lessons learned combined with previous composite radiator experiences were used to support the ALRDU design. The aforementioned experience was used to determine key CEV radiator design requirements used by Ball Aerospace and XCA for the ALRDU development.

Testing of the ALRDU was performed at NASA Johnson Space Center (JSC) in an integrated thermal vacuum system test. The integrated system was also based on an early design of the CEV Active Thermal Control System (ATCS), utilizing a Propylene-Glycol/Water plumped fluid loop. The testing evaluated the performance of the ALRDU with various flow schemes and determined the heat rejection capability of the radiator panel. Cold temperature stagnation capability and subsequent recoverability of individual fluid tubes was also demonstrated. The panel was tested at both steady state and transient conditions. The transient test points were completed to mimic a low lunar orbit thermal environment. Comparison between the test performance of the panel with thermal modeling demonstrated reasonable agreement. The test phase also proved the ALRDU fabrication technique to be a viable manufacturing process.