An ejector-based cryogenic refrigeration system for cold energy recovery includes a first cryogenic refrigeration loop connected by a helium compressor and a cryogenic refrigerator and a second cryogenic refrigeration loop connected by the helium compressor, a regenerator, an ejector, a cold head of the cryogenic refrigerator, an end to be cooled and a pressure regulating valve. The cryogenic refrigerator is separated from the end to be cooled. The cryogenic refrigerator and the cryogenic helium cooling loop share a helium compressor, which improves the utilization efficiency of the device and reduces the cost. The ejector allows a part of fluids to circulate in the cryogenic loop, so as to maintain a required cryogenic condition, recover the pressure of the fluids, reduce the gas flowing though the compressor loop, and thus reduce the power consumption of the compressor.

A refrigeration system can include a main flow circuit configured to flow a refrigerant therethrough and a heat input disposed in the main flow circuit and configured to receive heat and transfer the heat to the refrigerant in the main flow circuit to output heated refrigerant flow. The system can include a passive pump disposed in the main flow circuit downstream of the heat input configured to receive the heated refrigerant flow from the heat input and to use the heated refrigerant flow to generate a vacuum at a pump port and a condenser disposed in the main flow circuit downstream of the passive pump for receiving flow from the passive pump. The condenser can be configured to receive heat from the heated refrigerant flow and reject heat to cool the heated refrigerant flow to output partially cooled refrigerant flow. An outlet of the condenser can be upstream of the heat input.

A thermal management system includes a refrigerant receiver configured to store a refrigerant fluid, an evaporator arrangement that removes heat from a heat load converting a portion of the refrigerant fluid to refrigerant vapor and a liquid separator having an inlet, a liquid side outlet, and a vapor side outlet. The system also includes a pump that pumps refrigerant liquid received from the liquid side outlet of the liquid separator and a closed-circuit refrigeration system having a closed-circuit fluid path that includes the refrigerant receiver, the liquid separator, the pump, and the evaporator arrangement, the closed-circuit refrigeration system further including a compressor and a condenser. The system also including an open-circuit refrigeration system having an open-circuit fluid path that includes the refrigerant receiver, the liquid separator, the pump, and the evaporator arrangement, and further including a back-pressure regulator configured to receive refrigerant vapor from the vapor side outlet of the liquid separator and an exhaust line coupled to the outlet of the back-pressure regulator, with refrigerant vapor from the exhaust line not returning to the refrigerant receiver.

A thermal management system for a vehicle includes an ejector, which includes a main refrigerant line connected to allow a refrigerant to sequentially circulate through a compressor, a condenser and an evaporator, a first branch line which branches between the condenser and the evaporator of the main refrigerant line and which is connected to an inside of the nozzle of the ejector, a second branch line which branches between the evaporator and the compressor of the main refrigerant line and which is connected to an outside of the nozzle of the ejector, and a refrigerant increase line which is connected to an outlet of the ejector and which joins to the main refrigerant line through the compressor.

A thermal management system for a vehicle includes an ejector, which includes a main refrigerant line connected to allow a refrigerant to sequentially circulate through a compressor, a condenser and an evaporator, a first branch line which branches between the condenser and the evaporator of the main refrigerant line and which is connected to an inside of the nozzle of the ejector, a second branch line which branches between the evaporator and the compressor of the main refrigerant line and which is connected to an outside of the nozzle of the ejector, and a refrigerant increase line which is connected to an outlet of the ejector and which joins to the main refrigerant line through the compressor.

Disclosed herein is a refrigeration cycle includes a first refrigerant circuit configured to cause a refrigerant ejected from a compressor to flow through a condenser, an ejector, a first evaporator, and a second evaporator and flow back to the compressor; a second refrigerant circuit configured to cause the refrigerant to bypass the first evaporator in the first refrigerant circuit; and a third refrigerant circuit branching at a junction provided at a downstream end of the condenser from at least one of the first refrigerant circuit and the second refrigerant circuit, and configured to cause the refrigerant to flow through an expansion device and a third evaporator and flow to the ejector. By such configuration, a coefficient of performance (COP) of a refrigeration cycle may be improved and an ejector may be used to improve energy efficiency.

An aircraft air conditioning system comprising an ambient air supply line with a first end connected to an ambient air inlet and a second end connected to a mixing chamber. A first electrically driven ambient air compressor in the ambient air supply line compresses the ambient air flowing therethrough. A first ambient air branch line branches off from the ambient air supply line upstream of the first ambient air compressor and rejoins the supply line downstream of the air compressor. A second ambient air compressor in the first ambient air branch line compresses the ambient air flowing therethrough. A cabin exhaust air line has a first end connected to an air conditioned aircraft area. A cabin exhaust air turbine in the exhaust air line is driven by the exhaust air flowing through the cabin exhaust air line and is coupled to drive the second ambient air compressor.

An aircraft air conditioning system comprising an ambient air supply line with a first end connected to an ambient air inlet and a second end connected to a mixing chamber. A first electrically driven ambient air compressor in the ambient air supply line compresses the ambient air flowing therethrough. A first ambient air branch line branches off from the ambient air supply line upstream of the first ambient air compressor and rejoins the supply line downstream of the air compressor. A second ambient air compressor in the first ambient air branch line compresses the ambient air flowing therethrough. A cabin exhaust air line has a first end connected to an air conditioned aircraft area. A cabin exhaust air turbine in the exhaust air line is driven by the exhaust air flowing through the cabin exhaust air line and is coupled to drive the second ambient air compressor.

A vapor compression system (200; 400; 600; 700; 800; 900; 1000) comprises a plurality of valves (260, 262, 264; 260) controllable to define a first mode flowpath and a second mode flowpath. The first mode flowpath is sequentially through: a compressor (22); a first heat exchanger (30); a first nozzle (228; 624); and a separator (48), and then branching into: a first branch returning to the compressor; and a second branch passing through an expansion device (70) and a second heat exchanger (64) to the rejoin the flowpath between the first heat exchanger and the separator. The second mode flowpath is sequentially through: the compressor; the second heat exchanger; a second nozzle (248; 625); and the separator, and then branching into: a first branch returning to the compressor; and a second branch passing through the expansion device and first heat exchanger to the rejoin the flowpath between the first heat exchanger and the separator.

An approximately conical passage-forming member is disposed inside a body in which a swirling space for swirling a refrigerant is formed, and an ejector defines therein a nozzle passage that functions as a nozzle for depressurizing a refrigerant that has flowed out from the swirling space between an inner circumferential surface of the body and the passage-forming member, and a diffuser passage that pressurizes a mixed refrigerant obtained from a refrigerant sprayed from the nozzle passage and a refrigerant drawn from a suction-passage. A plurality of driving passages through which a refrigerant is introduced from a distribution space to the swirling space are formed in the body. In this case, the driving passages are formed in a manner such that a refrigerant flowing in from each driving passage into the swirling space flows along an outer circumference of the swirling space and flows in directions different from each other. Accordingly, nozzle efficiency is sufficiently improved.