The extrusion device of a solid film comprises a cell provided with an input opening of a material designed to form the solid film, and an output opening of the solid film from the cell. The device comprises a first heat exchanger for applying a first temperature to the output opening and a second heat exchanger for applying a second temperature in a first zone of the cell distinct from the output opening and a control circuit imposing first and second sets of first and second temperatures. The first set enables a volume of the material in solid phase to be formed. The second set enables a temperature gradient to be generated in the volume so as to generate a pressure forcing extrusion of the solid film via the output opening.

Systems and methods disclosed herein relate to a cryogenic refrigeration system which may use a compression based cryocooler or liquid nitrogen pre-cool to cool a medium to 80K, and may in conjunction with a magnetic refrigeration system operating in the sub-80K temperature regime to provide cooling to a medium to temperatures below 80K. In some embodiments, the disclosed system may be useful for cooling on the order of about 3 kg/day to about 300 kg/day of hydrogen gas to liquid form, with higher efficiency than a standard vapor compression based system. This higher efficiency may make the system a more attractive candidate for use in cryogenic cooling applications.

An active gas regenerative refrigerator includes a plurality of compressor-expander units, each having a hermetic cylinder with a drive piston configured to be driven reciprocally therein, and a quantity of working fluid in each end of the cylinder. A piston seal in a central portion of the cylinder prevents passage of the working fluid between ends of the cylinder. Movement of the piston to a first extreme results in radial compression of one of the quantities of working fluid in a cylindrical gap formed between one end of the piston and an inner surface of the cylinder, while the other quantity is expanded in the opposite end of the cylinder. The piston includes a plurality of magnets arranged in pairs, with magnets of each pair positioned with like-poles facing each other. A piston drive is configured to couple with transverse magnetic flux regions formed by the magnets.

An active gas regenerative refrigerator includes a plurality of compressor-expander units, each having a hermetic cylinder with a drive piston configured to be driven reciprocally therein, and a quantity of working fluid in each end of the cylinder. A piston seal in a central portion of the cylinder prevents passage of the working fluid between ends of the cylinder. Movement of the piston to a first extreme results in radial compression of one of the quantities of working fluid in a cylindrical gap formed between one end of the piston and an inner surface of the cylinder, while the other quantity is expanded in the opposite end of the cylinder. The piston includes a plurality of magnets arranged in pairs, with magnets of each pair positioned with like-poles facing each other. A piston drive is configured to couple with transverse magnetic flux regions formed by the magnets.

Disclosed is a small-scale hydrogen liquefaction system using cryocoolers. The system includes: a pre-cooling heat exchanger for pre-cooling gaseous hydrogen using liquid nitrogen; a first cryocooler that primarily cools the gaseous hydrogen, pre-cooled by the pre-cooling heat exchanger; a heat exchanger attached to a cold head of the first-cryocooler; an n-th cryocooler (wherein n is a natural number equal to or greater than two) that is connected in series with the first cryocooler and cools the gaseous hydrogen, primarily cooled by the first cryocooler, to a liquefaction temperature of 20.3 K; a condensation plate arranged to be in contact with the n-th cryocooler to liquefy the gaseous hydrogen, cooled to the temperature of 20.3 K by the n-th cryocooler; and a low-temperature chamber providing an accommodation space to accommodate the pre-cooling heat exchanger, the first cryocooler, and the n-th cryocooler.

A liquefier includes a Dewar having a storage portion and a neck portion extending therefrom. A hermetically isolated liquefaction chamber is disposed within the neck of the Dewar. One or more control components including a temperature and pressure sensor are coupled to a CPU and disposed within the liquefaction chamber for dynamic control of liquefaction conditions. A gas flow control is coupled to the CPU for regulating an input gas flow into the liquefaction chamber. A volume surrounding the liquefaction chamber may be adapted to provide a counter-flow heat exchange. These and other features provide improved liquefaction efficiency among other benefits.

An active gas regenerative refrigerator includes a plurality of compressor-expander units, each having a hermetic cylinder with a drive piston configured to be driven reciprocally therein, and a quantity of working fluid in each end of the cylinder. A piston seal in a central portion of the cylinder prevents passage of the working fluid between ends of the cylinder. Movement of the piston to a first extreme results in radial compression of one of the quantities of working fluid in a cylindrical gap formed between one end of the piston and an inner surface of the cylinder, while the other quantity is expanded in the opposite end of the cylinder. The piston includes a plurality of magnets arranged in pairs, with magnets of each pair positioned with like-poles facing each other. A piston drive is configured to couple with transverse magnetic flux regions formed by the magnets.

The present invention relates to a cryocooler suitable for gas liquefaction applications, that comprises a coldhead with one or more refrigeration stages; further comprising: a refrigerator compressor for distributing compressed gas-phase cryogen inside the coldhead; a heat exchanging coil arranged at least partially around the external region of the coldhead; at least one extraction orifice communicating a gas circulation circuit inside the coldhead with the heat exchanging coil; acting said extraction orifice/s as pass-through port/s which allow the gas inside the coldhead to flow through the inside of the heat exchanger coil for exchanging heat with the exterior thereof, and wherein the heat exchanging coil is adapted to connect and redirect the gas to one return port connected to the gas circulation circuit. Another object of the invention relates to a cryogen-gas liquefaction system and a method for liquefaction of gases that comprises said system.

The present invention discloses a hydrogen or helium throttling liquefaction system using direct current (DC) flow from the cold and hot ends of the regenerative cryocoolers, which belongs to the technical field of refrigeration and cryogenics. It includes a regenerative cryocooler module, a hot-end DC flow module, a cold-end DC flow module, a throttling liquefaction module, and a gas-phase circulation module. The modules are interconnected to form a closed loop for the flow of hydrogen or helium working fluid. DC flow is introduced from the cold and hot ends of the regenerative cryocooler through the DC flow pipelines and DC flow valves. The hot-end DC flow exchanges heat with the reflowing low-temperature working fluid and is cooled down. After that, it mixes with the cold-end DC flow and enters the throttling liquefaction module to generate liquid phase through throttling and liquefaction. After the liquid phase has output cooling capacity, it flows through the gas-phase circulation module and then enters the back-pressure chamber of the compressor to complete the cycle. Compared with the existing small-scale hydrogen and helium liquefaction technology using regenerative cryocoolers, the present invention has the advantages of simple structure, easy installation, high heat transfer efficiency and liquefaction efficiency of the system.

A dewar includes two coaxial openings of different sizes (e.g., to allow for interfacing with a Stirling cryocooler and a Stirling generator), a polytetrafluoroethylene or glass inner chamber (e.g., to reduce conductive heat transfer, particularly through the dewar neck), and an integrated, annular desiccant ring (e.g., for drying low-pressure, ambient air).