Solar Receiver Experiment for the Space Station Freedom Brayton Engine

An experimental investigation has been conducted to develop fabrication procedures and acquire test data for a heat receiver assembly (HRA) in support of the design and development effort for the Brayton engine solar receiver for the NASA Space Station Freedom solar dynamic option. The HRA configuration is a cylindrical receiver lined with tubes; each tube is surrounded by phase change material (PCM). The Brayton cycle working fluid flows inside the tubes. The PCM surrounding the tubes, a eutectic mixture of LiF and CaF₂, is contained in a series of sealed metallic containment canisters. During periods of sunlight, heat is transferred through the PCM to the Brayton cycle working fluid; during periods of eclipse, the PCM gives up its heat to the working fluid. A section of a full-size receiver tube was fabricated, assembled, and tested. Performance of the receiver tube qualitatively validates the expected receiver performance. Over 4500 cycles (of approximately 91-min duration) had been completed as of June 15, 1989.