The High-Capacity, Spaceborne, Vuilleumier Refrigerator

This paper describes the features and gives the thermal performance capabilities of the high-capacity (Hi Cap), Vuilleumier (VM), cryogenic refrigerator. This refrigerator simultaneously cools at three different temperature levels, the lowest being below 15 K. It is designed to cool electro-optical sensors in a spaceborne environment. The basic design of the Hi Cap refrigerator is discussed, and the individual machine elements are identified. Data on the thermal performance of this refrigerator is presented for various thermal load conditions on the three cold stages. The capability of this refrigerator for off-design-speed operation is also discussed.