A HIGH EFFICIENCY LOW VIBRATION LONG LIFE STIRLING CRYOGENICPRE-COOLER EMPLOYING FLEXURAL BEARINGS

STIRLING TECHNOLOGY COMPANY (STC) WILL DEVELOP AND TEST THE TECHNOLOGY DEMONSTRATION MODEL (TDM) MODEL OF A HIGH EFFICIENCY, LONG LIFE, LOW VIBRATION CRYOFLEX DOUBLE-EXPANSION CRYOGENIC PRE-COOLER TO BE USED AS A STANDARD FLIGHT PRE-COOLER FOR REJECT HEAT REMOVAL FROM ALTERNATIVE VERY LOW TEMPERATURE CRYOCOOLER STAGES. THE KEY OBJECTIVES FOR THE CRYOGENIC PRE-COOLER ARE HIGH EFFICIENCY, LOW VIBRATION, AND 10- TO 15-YEAR LIFE. THE CRYOGENIC PRE-COOLER WILL BE OPTIMIZED FOR HEAT REMOVAL FROM SOURCES IN THE 20 K TEMPERATURE RANGE. NASA AND STC WILL COOPERATIVELY DEFINE HEAT LIFTING CAPACITY, SOURCE TEMPERATURE AND OTHER CRITICAL PERFORMANCE OBJECTIVES. HIGH EFFICIENCY WILL BE ACHIEVED THROUGH THE MINIMIZATION OF DEAD VOLUME IN A DOUBLE-EXPANSION STIRLING DEVICE, CAREFUL SELECTION AND IMPLEMENTATION OF ADVANCED REGENERATORTECHNOLOGY, OPTIMIZED ELECTRIC MOTOR DESIGN, AND USE OF FLEXURAL BEARINGS FOR HIGH MECHANICAL EFFICIENCY. CO-LINEARITY OF OSCILLATING MASSES COUPLED WITH EITHER DUAL OPPOSED PISTON TECHNOLOGY OR AN ACTIVE BALANCER WITH ADAPTIVE CONTROL WILL RESULT IN TRACE LEVELS OF VIBRATION. FLEXURAL BEARINGS AND GAS CLEARANCE SEALS WILL PROVIDE 10- TO 15-YEAR LIFE. THE PHASE I OBJECTIVE IS COMPLETION OF THE TDM CONCEPTUAL DESIGN. PHASE II OBJECTIVES INCLUDE DESIGN, FABRICATION, ASSEMBLY, TESTING AND EVALUATION OF THE TDM.