Enclosed capillary device for low gravity management of He II

To transfer He II in space, a large tank must be drained at low gravity. This paper describes and analyzes an enclosed gallery device designed for collecting and delivering He II to a pump. The device allows most of the liquid to move about in the tank while it maintains a liquid flow to the pump. Only the liquid in the screen-covered gallery channels and in the upper and lower receivers is contained. The device operates by providing surface tension dominated liquid paths from all locations within the tank to the lower receiver, which houses the pump. Since the fluid pressure in the channels may be below the saturated vapor pressure, an analysis of He II cavitation is performed to determine if cavitation will occur. The effect of heat dissipation from the pump is examined to determine if it may result in nucleation of boiling. It is concluded that this enclosed device can meet the requirements for transfer of He II under the predicted adverse accelerations that will be encountered on-orbit.