Development of a dual flow transfer system with a centrifugal pump for liquid helium

Abstract

Abstract At research institutes, liquid helium is commonly transferred to mobile dewar vessels via a single flow transfer line, driven by a pressure build-up in the storage vessel. In this process, a considerable amount of the liquid evaporates according to the prevailing pressure drop and due to the heat leak into the transfer line. Further, the generated flash gas must undergo an energy intensive recovery and liquefaction procedure again. To significantly reduce these transfer losses, the cryogen can be transferred to the target dewar using a centrifugal pump. At the same time, the displaced cold gas is guided back to the storage dewar in a cold return line within the same insulated transfer housing. This article presents the current development status of the transfer system, including the thermo-hydraulic modeling and simulation.