A switching mechanism (TV1, TV2, TV3, TV4, FV) includes an electric motor (74), a flow path switching portion (71) to be driven by the electric motor (74), a first port (P1) connected to a high-pressure flow path (7, 24, 28b, 31, 32) of a refrigerant circuit (6), a second port (P2) connected to a low-pressure flow path (8, 25, 28a, 33, 34) of the refrigerant circuit (6), and a third port (P3) connected to a predetermined flow path of the refrigerant circuit (6). The switching mechanism (TV1, TV2, TV3, TV4, FV) is switched between a first state in which the first port (P1) communicates with the third port (P3) and a second state in which the second port (P2) communicates with the third port (P3) in such a manner that the electric motor (74) drives the flow path switching portion (71).

Provided are mixed refrigerant systems and methods and, more particularly, to a mixed refrigerant system and methods that provides greater efficiency and reduced power consumption via control of a liquid level in a cold vapor separator device.

A multistage compression system uses refrigerant and oil. The multistage compression system includes a low-stage compressor that compresses the refrigerant, a high-stage compressor that further compresses the refrigerant compressed by the low-stage compressor, and an oil return pipe that returns the oil discharged by the high-stage compressor or the oil in the high-stage compressor to the low-stage compressor. The low-stage compressor has a rotary compression part that compresses the refrigerant, a motor that drives the compression part, and a container housing the compression part and the motor. The motor is disposed above the compression part. The oil return pipe is connected to a space below the motor inside the container.

Simplified closed loop refrigeration system adapted for cryogenic temperatures comprising: a gaseous refrigerant circulating inside the closed loop refrigeration system, a compression section for compressing the refrigerant with at least two compressor stages, at least one of the compressor stages being one centrifugal compressor, at least a motor producing mechanical power to drive at least one of the compressor stages, at least an after cooler after each compression stage, a first heat exchanger for additionally cooling the compressed refrigerant, at least one expansion turbine for expanding the compressed refrigerant, a second heat exchanger for exchanging heat between the expanded refrigerant and an external fluid, a heating section where the expanded refrigerant is heated in counter-current flow inside the first heat-exchanger by the compressed refrigerant, wherein at least one centrifugal compressor being driven only by the expansion turbine and the centrifugal compressors and the expansion turbine use magnetic bearings.

A refrigeration system includes: a compressor arrangement for compressing gaseous refrigerant from a first pressure to a second pressure, wherein the second pressure comprises a condensing pressure; a plurality of condenser evaporator systems, wherein each condenser evaporator system comprises: a condenser for receiving gaseous refrigerant at a condensing pressure and condensing the refrigerant to a liquid refrigerant; a controlled pressure receiver for holding the liquid refrigerant from the condenser; and an evaporator for evaporating liquid refrigerant from the controlled pressure receiver to form gaseous refrigerant; a first gaseous refrigerant feed line for feeding the gaseous refrigerant at the second pressure from the compressor arrangement to the plurality of condenser evaporator systems; and a second gaseous refrigerant feed line for feeding gaseous refrigerant from the plurality of condenser evaporator systems to the compressor arrangement.

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.

A cooling system includes a heat exchanger through which a refrigerant flows, the heat exchanger having a fluid passing therethrough such that heat is rejected to the fluid, an evaporator, a refrigerant piping split point that receives the refrigerant at a given pressure from the heat exchanger and splits the refrigerant flow into a first circuit and a second circuit, the first circuit having an expansion valve that receives the refrigerant at the given pressure, and the second circuit having a first turbine coupled to a first compressor, wherein the first turbine receives the refrigerant at the given pressure, and a set of valves arranged to direct the refrigerant through the first circuit, the second circuit, or both the first and second circuits based on ambient conditions of the cooling system.

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.

The present invention relates to a gas heat pump system. A gas heat pump system according to one embodiment of the present invention comprises: a compressor for compressing a refrigerant; a gas engine for driving the compressor; a mixer for mixing air and fuel to generate a mixed gas to be supplied to the gas engine; a mixed gas supply line connected between the mixer and the gas engine; and a supercharger for supercharging the mixed gas supplied to the gas engine through the mixed gas supply line, wherein the supercharger comprises a sealed housing formed by sealing the remaining parts thereof other than an inlet port and an outlet port through which the mixed gas moves into and out of the housing, and a bypass line is provided between the sealed housing and the inlet port of the supercharger so as to resupply a mixed gas in the sealed housing to the inlet port of the supercharger. Therefore, the system can prevent a safety-related accident resulting from the leakage of the mixed gas out of the supplier and can reduce the amount of fuel consumption.

An apparatus includes a flash tank, a first low side heat exchanger, a second low side heat exchanger, a first compressor, a second compressor, an expansion valve, a desuperheater, a sensor, and a controller. The first compressor compresses a refrigerant from the second low side heat exchanger. The desuperheater removes heat from the refrigerant from the first compressor. The second compressor compresses a mixture of the refrigerant from the first low side heat exchanger and the refrigerant from the first compressor. The expansion valve, actionable by the sensor and the controller, controls a flow of the refrigerant to the first low side heat exchanger such that the flow of refrigerant to the first low side heat exchanger is increased when a temperature of the mixture exceeds a threshold.