A refrigeration apparatus includes first and second refrigeration circuits, and a supercooling circuit. The supercooling circuit includes a supercooling bypass flow path which communicates a part of the first refrigeration circuit positioned on the downstream side of the condenser and on the upstream side of the first expansion valve, to a compressor on the first refrigeration circuit; a supercooling control valve; and a supercooling heat exchanger disposed on the downstream side of the supercooling control valve in the supercooling bypass flow path. The supercooling heat exchanger is configured to cool the refrigerant flowing through a part of the first refrigeration circuit, on the downstream side of a connection position to the supercooling bypass flow path. The second refrigeration circuit includes: a branch flow path which branches from a part of the first refrigeration circuit, on the upstream side of the connection position to the supercooling bypass flow path.

A compressor with a touchdown bearing and a supply line for injecting a working fluid toward the touchdown bearing, and a vapor compression system incorporating the same are provided. The supply line injects working fluid approximately continuously when the compressor is operational. The compressor includes a magnetic bearing for levitating the rotating shaft when the compressor is operational. The touchdown bearing is used to support the rotating shaft when the compressor is shutdown. The touchdown bearing may be disposed, at least partially, between a pair of races. The injecting of the working fluid may cause the touchdown bearing to rotate between the races. The injecting of the working fluid may help mitigate a buildup of a debris between the touchdown bearing and the races.

A temperature control system includes: first and second refrigerator units; a first fluid flow apparatus that allows a first fluid to flow therethrough and that is cooled by the first refrigerator unit; a second fluid flow apparatus that allows a second fluid to flow therethrough and that is cooled by the second refrigerator unit; and a valve unit that is configured to allow the first fluid or the second fluid to selectively flow out therefrom. The first refrigerator unit has, in a medium-temperature-side refrigerator, a medium-temperature-side first expansion valve and a medium-temperature-side second expansion valve. A medium-temperature-side second evaporator corresponding to the medium-temperature-side second expansion valve and a low-temperature-side condenser of a low-temperature-side refrigerator constitute a cascade condenser. The first fluid is cooled by a medium-temperature-side first evaporator corresponding to the medium-temperature-side first expansion valve, and is then cooled by a low-temperature-side evaporator of the low-temperature-side refrigerator.

A heat transfer circuit includes a compressor, a condenser, an expander, and an evaporator. The compressor includes a shaft that is rotated to compress a working fluid and a gas bearing to support the shaft. A conduit is configured to supply a portion of the working fluid to the compressor to cool the gas bearing. A method of controlling a heat transfer circuit includes directing a working fluid through a main flow path of the heat transfer circuit that directs the working fluid through a compressor, a condenser, an expander, an evaporator, and back to the compressor. The method also includes suppling supplying a portion of the working fluid in the main flow path to the compressor to cool a gas bearing of the compressor.

A fluid temperature control system cools a fluid by means of a multiple refrigeration apparatus including a high-temperature-side refrigerator (100), a medium-temperature-side refrigerator (200) and a low-temperature-side refrigerator (300). The medium-temperature-side refrigerator (200) in the multiple refrigeration apparatus has a medium-temperature-side first evaporator (204) and a medium-temperature-side second evaporator (224). A high-temperature-side evaporator (104) of the high-temperature-side refrigerator (100) and a medium-temperature-side condenser (202) of the medium-temperature-side refrigerator (200) constitute a first cascade condenser (CC1). The medium-temperature-side second evaporator (224) of the medium-temperature-side refrigerator (200) and a low-temperature-side condenser (302) of the low-temperature-side refrigerator (300) constitute a second cascade condenser (CC2). The medium-temperature-side refrigerant and the low-temperature-side refrigerant are the same refrigerant. The fluid allowed to flow by a fluid flow apparatus is cooled by the medium-temperature-side first evaporator (204) of the medium-temperature-side refrigerator (200), and is then cooled by the low-temperature-side evaporator (304) of the low-temperature-side refrigerator (300).

A system for reducing the refrigerant pressure in an oil sump or in a cavity of a housing. The invention is particularly useful for reducing pressure in a compressor for heat pump applications that has been validated for water chiller operations or in turbine and generator systems in ORC systems generating electricity using refrigerant, the ORC systems essentially being a heat pump application operating in reverse. An auxiliary compressor, an auxiliary condenser or an ejector pump may be used to reduce pressure in the oil sump, to separate refrigerant from oil. The auxiliary compressor, the auxiliary condenser or the ejector pump may also be used to reduce the pressure of refrigerant in the housing of a compressor in heat pump applications at temperatures and pressures at which the compressor was validated for water chiller applications and of the turbine and generator in ORC applications.

An air conditioner according to an embodiment includes: a compressor configured to compress a refrigerant; an indoor heat exchanger configured to convert a vapor refrigerant into a liquid refrigerant in a heating mode; an outdoor heat exchanger configured to convert a liquid refrigerant into a vapor refrigerant in the heating mode; a main pipe connecting the indoor heat exchanger to the outdoor heat exchanger; an injection pipe branching from the main pipe and connecting to an injection port of the compressor; an injection valve installed on the injection pipe and configured to control a flux of the refrigerant flowing to the injection pipe; and a controller configured to calculate a target discharge superheat (DSH) based on a correlation between a compression coefficient, a compressor frequency, and a DSH that are represented by an operating condition , and control a current DSH based on the target DSH.

Disclosed is an artificial refrigerator. The artificial refrigerator according to the present disclosure includes at least one sensor for sensing an operation state of the refrigerator and obtaining operation information about the operation state of the refrigerator and a processor that determines whether the operation state of the refrigerator is normal or abnormal using a deep-learning-based first diagnosis engine based on the operation information obtained using the at least one sensor and diagnoses, upon determination of the abnormality, a cause of the abnormality using a deep-learning-based second diagnosis engine. In the artificial refrigerator of the present invention, at least one of a user terminal or a server may be associated with an artificial intelligence module, a drone (Unmanned Aerial Vehicle, UAV) robot, an augmented reality (AR) device, a virtual reality (VR) device, a device related to a 5G service, and the like.

A fluid temperature control system according to an embodiment cools a fluid by means of a multiple refrigeration apparatus including a high-temperature-side refrigerator, a medium-temperature-side refrigerator and a low-temperature-side refrigerator. The medium-temperature-side refrigerator in the multiple refrigeration apparatus has a medium-temperature-side first evaporator and a medium-temperature-side second evaporator. A high-temperature-side evaporator of the high-temperature-side refrigerator and a medium-temperature-side condenser of the medium-temperature-side refrigerator constitute a first cascade condenser. The medium-temperature-side second evaporator of the medium-temperature-side refrigerator and a low-temperature-side condenser of the low-temperature-side refrigerator constitute a second cascade condenser. The fluid allowed to flow by a fluid flow apparatus is cooled by the medium-temperature-side first evaporator of the medium-temperature-side refrigerator, and is then cooled by the low-temperature-side evaporator of the low-temperature-side refrigerator.

Embodiments of the present invention reduce the amount of energy required to operate air-conditioners and refrigerators by providing a vapor-compression system that harnesses a low- or no-cost source of energy, namely, heat, and uses the harnessed heat to power a new kind of compressor, called a burst compressor and a new kind of pump, called a vapor pump. The heat-driven burst compressor pressurizes the refrigerant, while also providing push and pull vapor refrigerant to the vapor pump. The vapor pump, actuated by the high pressure refrigerant in gaseous form provided by the burst compressor, is configured to pump a combination of gaseous, vaporous and liquid refrigerant out of the receiver tank and inject that low pressure refrigerant mix into the burst compressor, where it is heated to change the state of the refrigerant to a heated, pressurized gas. Then the heated, pressurized gas is released in bursts into the other components of the vapor compression cycle. Thus, embodiments of the present invention use heat to provide cold. Because of this arrangement, vapor-compression systems constructed and arranged to operate according to embodiments of the present invention are able to provide air-conditioning and/or refrigeration much more efficiently and with much less expense than traditional vapor compression systems for air-conditioning and refrigeration.