Pressurized Transfer of Cryogenic Liquids

Abstract

The term “gas-pressurized liquid transfer” applies to a process in which the force required to pump the liquid is obtained from a high pressure gas that acts as a piston on the free surface of an upstream liquid reservoir. Ordinarily, liquids are transferred by pumps. Gas pressurized transfer systems may, however, be preferred to pumping systems in some cases. Infrequent, intermittent pump operation may not provide economic justification for the installation of large pumps, large standby power facilities, and associated control gear. A practical example which may be cited is the transfer of liquid propellants to missiles. Here, the transfer operation is quite infrequent, and must be carried out rapidly at a time when there is a maximum drain in the base power supply and with the minimum of heat energy transfer into the fluid.