Experimental investigation of a dual flow transfer system for liquid helium

Abstract In transfer stations for liquid helium, single-flow transfer lines are often used to transfer the liquid into a smaller mobile dewar. During this process, a considerable amount of the liquid evaporates due to heat leak and especially due to pressure losses in the transfer line. Regardless of the liquefier’s efficiency, this evaporation loss contributes to a significantly higher running time of the cold box and a higher primary energy input to generate the net liquid volume. To overcome this, a laboratory setup was realized by a combination of a flexible double-flow transfer line and a cold liquid pump, which can reduce these losses drastically. In this article, the authors report on their current test results on filling performance, operating losses and practicability.