Purchase Order NNX11CG01P

FUTURE INSTRUMENTS AND PLATFORMS FOR NASA SPACE APPLICATIONS WILL REQUIRE INCREASINGLY SOPHISTICATED THERMAL CONTROL TECHNOLOGY, AND CRYOGENIC APPLICATIONS WILL BECOME INCREASINGLY MORE COMMON. FOR EXAMPLE, THE SINGLE APERTURE FAR-IR (SAFIR) TELESCOPE AND OTHER CRYOGENIC TELESCOPE MISSIONS MUST PROVIDE DISTRIBUTED COOLING AND MULTIPLE HEAT LIFT. ALSO, THE MANAGEMENT OF CRYOGENIC PROPELLANTS REQUIRES DISTRIBUTED COOLING THROUGH INTEGRATED HEAT EXCHANGERS FOR ZERO BOIL-OFF, DENSIFICATION AND COOLING OF STRUCTURAL MEMBERS. TO ADDRESS THESE REQUIREMENTS, WE PROPOSE TO DEVELOP A LIGHTWEIGHT, CONTINUOUS-FLOW COOLING LOOP THAT CAN PROVIDE COOLING AND TEMPERATURE CONTROL TO MULTIPLE, DISTRIBUTED AND BROAD AREA LOADS. THIS APPROACH ALLOWS RELATIVELY SIMPLE MECHANICAL AND ELECTRICAL INTEGRATION AND MAINTAINS HIGH REFRIGERATION SYSTEM EFFICIENCY. THE BASIS OF THE LOOP IS A SET OF COLD CHECK VALVES THAT CONVERTS THE OSCILLATING PRESSURE, WHICH CHARACTERIZES THE OPERATION OF REGENERATIVE CRYOCOOLERS, INTO A QUASI-STEADY PRESSURE DIFFERENCE THAT CAN BE USED TO DRIVE A CONTINUOUS FLOW OF COLD GAS OVER DISTANCES OF SEVERAL METERS. THIS INTEGRATED CIRCULATOR (IC) HAS THE POTENTIAL SECONDARY BENEFIT OF RAPID AND THEREFORE PRECISE LOAD TEMPERATURE REGULATION OF MULTIPLE SENSORS OR STRUCTURES USING ACTIVELY CONTROLLED THROTTLE VALVES TO REGULATE THE LOCAL GAS FLOW.