The position of the stabilizer container 7 in the circulation route is not limited. The stabilizer container 7 is preferably disposed between the evaporator and the condenser between which the refrigerant flows in the circulation route as a liquid refrigerant. Specifically, the stabilizer container 7 is preferably disposed between the outdoor heat exchanger 4 and the expansion mechanism 5 or between the indoor heat exchanger 6 and the expansion mechanism 5. During cooling, the outdoor heat exchanger 4 functions as a condenser and the indoor heat exchanger 6 functions as an evaporator. During heating, the outdoor heat exchanger 4 functions as an evaporator and the indoor heat exchanger 6 functions as a condenser. In either case of cooling or heating, the liquid refrigerant is present between the expansion mechanism 5 and the outdoor heat exchanger 4 or between the expansion mechanism 5 and the indoor heat exchanger 6 depending on the refrigerant circulation direction, and the stabilizer container 7 is located where the liquid refrigerant is present (i.e., between the expansion mechanism and whichever heat exchanger 4, 6 serves as the evaporator in the refrigerant circulation direction). Thus, as the liquid refrigerant passes through the stabilizer container 7, oxidation of the refrigerant can be efficiently prevented and acids in the circulation route can be efficiently scavenged.

Low-temperature refrigeration device arranged in a frame and comprising a working circuit forming a loop and containing a working fluid, the working circuit forming a cycle comprising in series: a compression mechanism, a cooling mechanism, an expansion mechanism and a heating mechanism, the device comprising a refrigeration heat exchanger intended to extract heat from at least one member by exchanging heat with the working fluid, the mechanisms for cooling and reheating the working fluid comprising a common heat exchanger in which the working fluid transits in counter-flow in two separate transit portions of the working circuit, the compression mechanism comprising at least two compressors and at least one motor for driving the compressors, the working fluid expansion mechanism comprising at least one rotary turbine, the device comprising at least one drive motor comprising a drive shaft, one end of which drives a compressor and the other end of which is coupled to a turbine, the motor being attached to the frame at at least one fixed point, the common heat exchanger being attached to the frame at at least one fixed point, the two counter-flow transit portions of the common heat exchanger being orientated in a longitudinal direction of the frame, the drive shaft of the drive motor being orientated in a direction parallel or substantially parallel to the longitudinal direction and the turbine and the compressor being arranged relatively longitudinally such that the turbine is located longitudinally on the side corresponding to the relatively cold end of the common heat exchanger when the device is being operated and the compressor is located longitudinally on the side corresponding to the relatively hot end of the common heat exchanger when the device is being operated.

Low-temperature refrigeration device arranged in a frame and comprising a working circuit forming a loop and containing a working fluid, the working circuit forming a cycle comprising in series: a compression mechanism, a cooling mechanism, an expansion mechanism and a heating mechanism, the device comprising a refrigeration heat exchanger intended to extract heat from at least one member by exchanging heat with the working fluid, the mechanisms for cooling and reheating the working fluid comprising a common heat exchanger in which the working fluid transits in counter-flow in two separate transit portions of the working circuit, the compression mechanism comprising at least two compressors and at least one motor for driving the compressors, the working fluid expansion mechanism comprising at least one rotary turbine, the device comprising at least one drive motor comprising a drive shaft, one end of which drives a compressor and the other end of which is coupled to a turbine, the motor being attached to the frame at at least one fixed point, the common heat exchanger being attached to the frame at at least one fixed point, the two counter-flow transit portions of the common heat exchanger being orientated in a longitudinal direction of the frame, the drive shaft of the drive motor being orientated in a direction parallel or substantially parallel to the longitudinal direction and the turbine and the compressor being arranged relatively longitudinally such that the turbine is located longitudinally on the side corresponding to the relatively cold end of the common heat exchanger when the device is being operated and the compressor is located longitudinally on the side corresponding to the relatively hot end of the common heat exchanger when the device is being operated.

Provided is grease capable of suppressing a decrease in a function as a lubricant even when used in a device installed in a refrigerant circuit in which a refrigerant containing a chlorine atom and an olefin bond in a molecule flows, and a refrigeration cycle apparatus using the grease as a lubricant. Grease that is used in a device installed in a refrigerant circuit in which a refrigerant containing a chlorine atom and an olefin bond in a molecule flows contains fluorine as a component. In a chiller apparatus, the grease is used as a lubricant for at least one of a first radial touchdown bearing and a second radial touchdown bearing of a compressor, a drive portion of an inlet guide vane of the compressor, and a drive portion of an expansion valve.

Provided is grease capable of suppressing a decrease in a function as a lubricant even when used in a device installed in a refrigerant circuit in which a refrigerant containing a chlorine atom and an olefin bond in a molecule flows, and a refrigeration cycle apparatus using the grease as a lubricant. Grease that is used in a device installed in a refrigerant circuit in which a refrigerant containing a chlorine atom and an olefin bond in a molecule flows contains fluorine as a component. In a chiller apparatus, the grease is used as a lubricant for at least one of a first radial touchdown bearing and a second radial touchdown bearing of a compressor, a drive portion of an inlet guide vane of the compressor, and a drive portion of an expansion valve.

A compressor according to an exemplary aspect of the present disclosure includes, among other things, a mixed compression stage having both axial and radial components arranged along a main flow path, and a radial compression stage having an impeller with a plurality of vanes arranged in the main flow path downstream of the mixed compression stage. The impeller is configured to rotate about an axis and has an outlet downstream of the vanes. A movable diffuser is arranged at the outlet, and the movable diffuser is configured to vary an area of the outlet.

A compressor according to an exemplary aspect of the present disclosure includes, among other things, a mixed compression stage having both axial and radial components arranged along a main flow path, and a radial compression stage having an impeller with a plurality of vanes arranged in the main flow path downstream of the mixed compression stage. The impeller is configured to rotate about an axis and has an outlet downstream of the vanes. A movable diffuser is arranged at the outlet, and the movable diffuser is configured to vary an area of the outlet.

Disclosed is a low-temperature refrigeration device comprising a working circuit that forms a loop and contains a working fluid the working circuit forming a cycle which includes, connected in series: a compression mechanism, a cooling mechanism, an expansion mechanism and a heating mechanism, the device further comprising a refrigeration heat exchanger for extracting heat from at least one member by exchanging heat with the working fluid flowing in the working circuit, the compression mechanism comprising two separate compressors, the mechanism for cooling the working fluid comprising two cooling heat exchangers which are arranged respectively at the outlet of the two compressors and ensure heat exchange between the working fluid and a cooling fluid, each cooling heat exchanger comprising a cooling fluid inlet and a cooling fluid outlet, characterized in that the cooling fluid outlet of one of the two cooling heat exchangers is connected to the cooling fluid inlet of the other cooling heat exchanger.

Disclosed is a refrigeration and/or liquefaction method using a system that includes a low-temperature refrigeration device comprising a working circuit which forms a loop and contains a working fluid, the working circuit forming a cycle comprising, connected in series: a compression mechanism, a cooling mechanism, an expansion mechanism and a heating mechanism the refrigeration device further comprising a cooling exchanger for extracting heat from the useful fluid stream by exchanging heat with the working fluid flowing in the working circuit, the system comprising a pipe through which the useful fluid stream flows in the cooling exchanger, the method comprising a cooling step in which the refrigeration device is in a first operating mode for cooling the cooling exchanger while a useful fluid stream flows in the cooling exchanger, the method comprising, after said cooling step, a step of cleaning impurities that have solidified in the cooling exchanger, characterized in that during the cleaning step, the refrigeration device is in a second operating mode in which the working gas flows in the working circuit but in which the cooling exchanger cools less intensely than in the first operating mode.

Disclosed is a refrigeration and/or liquefaction method using a system that includes a low-temperature refrigeration device comprising a working circuit which forms a loop and contains a working fluid, the working circuit forming a cycle comprising, connected in series: a compression mechanism, a cooling mechanism, an expansion mechanism and a heating mechanism the refrigeration device further comprising a cooling exchanger for extracting heat from the useful fluid stream by exchanging heat with the working fluid flowing in the working circuit, the system comprising a pipe through which the useful fluid stream flows in the cooling exchanger, the method comprising a cooling step in which the refrigeration device is in a first operating mode for cooling the cooling exchanger while a useful fluid stream flows in the cooling exchanger, the method comprising, after said cooling step, a step of cleaning impurities that have solidified in the cooling exchanger, characterized in that during the cleaning step, the refrigeration device is in a second operating mode in which the working gas flows in the working circuit but in which the cooling exchanger cools less intensely than in the first operating mode.