DEVELOPMENT OF AN INNOVATIVE LIQUID HELIUM PUMP

THIS PROJECT WILL DEVELOP A RELIABLE, HIGH EFFICIENCY, VERSATILE LIQUID HELIUM (LHE) PUMP FOR THE SUPERCONDUCTING SUPER COLLIDER (SSC). SEVERAL INNOVATIVE DESIGN FEATURES WILL BE INCORPORATED TO GIVE THE PUMP THE FOLLOWING CHARACTERISTICS: 1) A HERMETIC DESIGN WILL ELIMINTE ALL DYNAMIC SEALS, 2) A NON-CONTAMINATING, RELIABLE BEARING SYSTEM WILL NOT DISSIPATE ANY POWER TO THE LHE, 3) THERMAL ISOLATION WILL LIMIT HEAT TRANSFER TO LHE TO LESS THAN 2 W, 4) A FULL EMISSION CENTRIFUGAL PUMPING ELEMENT WILL ACHIEVE 80%-85% DESIGN POINT EFFICIENCY, 5) A VARIABLE SPEEDINDUCTION MOTOR DRIVE WILL MAINTAIN NEAR DESIGN POINT EFFICIENCY DOWN TO 20% OF THE DESIGN FLOW RATE FOR CIRCULATION APPLICATIONS (WHERE HEAD RISE IS PROPORTIONAL TOTHE SQUARE OF THE FLOW RATE, 6) ADJUSTABLE GEOMETRY PUMP FEATURES WILL ACHIEVE 60% EFFICIENCY AT 20% OF THE DESIGN FLOW RATE FOR TRANSFER PUMP APPLICATIONS (WHERE CONSTANT HEAD RISE IS REQUIRED OVER THE ENTIRE RANGE OF FLOW RATES), 7) THE PUMP WILL BE CAPABLE OF CIRCULATING HELIUM VAPOR DURING SYSTEM COOL DOWN. THE PHASE I OBJECTIVES ARE TWO FOLD: 1) TO INVESTIGATE KEY FEASIBILITY ISSUES AND IDENTIFY THE MOST PROMISING SOLUTION, AND 2) TO FABRICATE AND CONDUCTNON-CRYOGENIC TESTS OF THE PUMP ASSEMBLY TO DEMONSTRATE PROOF-OF-CONCEPT. THIS WORK WILL PROVIDE A SOUND BASIS FOR THE PHASE II SCOPE OF WORK WHICH WILL INCLUDE THE FURTHER DEVELOPMENT AND CRYOGENIC TESTING OF A PROTOTYPE PUMP.