A system includes a pressure exchanger (PX) configured to receive a first fluid at a first pressure, receive a second fluid at a second pressure, and exchange pressure between the first fluid and the second fluid. The first fluid is to exit the PX at a third pressure and the second fluid is to exit the PX at a fourth pressure. The system further includes a first heat exchanger configured to provide the first fluid to the PX and provide corresponding thermal energy from the first fluid to a third fluid. The system further includes a turbine configured to receive the third fluid output from the first heat exchanger. The turbine is further configured to convert corresponding thermal energy of the third fluid into kinetic energy.

A fluid handling system includes a pressure exchanger (PX) configured to receive a first fluid at a first pressure and a second fluid at a second pressure and exchange pressure between the first fluid and the second fluid. The system further includes a condenser configured to provide corresponding thermal energy from the first fluid to a corresponding environment. The system further includes a receiver to receive the first fluid output by the PX. The receiver forms a chamber to separate the first fluid into a first gas and a first liquid. The system further includes a first booster to increase pressure of a portion of the first gas to form the second fluid at the second pressure and provide the second fluid at the second pressure to the PX.

A method for controlling a vapour compression system (1) is disclosed, the vapour compression system (1) comprising at least one expansion device (8) and at least one evaporator (9). For each expansion device (8), an opening degree of the expansion device (8) is obtained, and a representative opening degree, OD.sub.rep, is identified based on the obtained opening degree(s) of the expansion device(s) (8). The representative opening degree could be a maximum opening degree, OD.sub.max, being the largest among the obtained opening degrees. The representative opening degree, OD.sub.rep, is compared to a predefined target opening degree, OD.sub.target, and a minimum setpoint value, SP.sub.rec, for a pressure prevailing inside a receiver (7), is calculated or adjusted, based on the comparison. The vapour compression system (1) is controlled to obtain a pressure inside the receiver (7) which is equal to or higher than the calculated or adjusted minimum setpoint value, SP.sub.rec.

An ejector includes a shaft coupled to a passage formation member defining a refrigerant passage inside a body, and the shaft is slidably supported by a support member fixed to the body. A drive mechanism moves the shaft in an axial direction to change a passage sectional area of the refrigerant passage. The passage formation member is provided with a vibration suppressive member including a first mobile end that applies a load to enlarge the refrigerant passage and a second mobile end that applies a load to narrow the refrigerant passage. Both the first mobile end and the second mobile end are disposed on a same side of a slide region of the support member in the axial direction.

Disclosed is a refrigeration system having: a steam ejector with an ejector outlet; and a passive flow trap connected to the ejector outlet.

A method for controlling a vapour compression system (1) is disclosed. The vapour compression system (1) includes an ejector (4), and has a non-return valve (11) arranged in the refrigerant path between an outlet (12) of an evaporator (7) and an inlet (10) of a compressor unit (2), in such a manner that a refrigerant flow from the outlet (12) of the evaporator (7) towards the inlet (10) of the compressor unit (2) is allowed, while a fluid flow from the inlet (10) of the compressor unit (2) towards the outlet (12) of the evaporator (7) is prevented. A pressure, P.sub.0, of refrigerant leaving the evaporator (7) is measured and a value being representative for a pressure, P.sub.suc, of refrigerant entering the compressor unit (2) is obtained. The pressures, P.sub.0 and P.sub.suc, are compared to respective reference pressure values, P.sub.0,ref and P.sub.suc,ref. In the case that ε.sub.0>ε.sub.suc, where ε.sub.0=P.sub.0−P.sub.0,ref and ε.sub.suc=P.sub.suc−P.sub.suc,ref, the compressor unit (2) is controlled based on P.sub.0, and in the case that ε.sub.suc>ε.sub.0, the compressor unit (2) is controlled based on P.sub.suc.

A refrigerated system includes a heat recovery system defining a heat recovery fluid flow path. The heat recovery system includes an ejector having a primary inlet and a secondary inlet and a first heat exchanger within which heat is transferred between a heat recovery fluid and a secondary fluid. The first heat exchanger is located upstream from the primary inlet of the ejector. A second heat exchanger within which heat is transferred from a heat transfer fluid to the heat recovery fluid is upstream from the secondary inlet of the ejector. At least one recovery heat exchanger is positioned along the heat recovery fluid flow path directly upstream from the first heat exchanger.

A refrigeration system for a carbon dioxide based refrigerant fluid, wherein the refrigeration system includes a refrigerant circuit, the refrigerant circuit including a compression device, a heat rejecting heat exchanger, an ejector, a receiver, an expansion device, and a heat absorbing heat exchanger; wherein the ejector includes a primary inlet, a secondary inlet and an outlet; wherein the receiver includes an inlet, a liquid outlet and a gas outlet; wherein the ejector primary inlet is arranged to receive fluid from an outlet of the heat rejecting heat exchanger, the ejector secondary inlet is arranged to receive fluid from an outlet of the heat absorbing heat exchanger, and the ejector outlet is arranged to direct flow to the receiver inlet; wherein a suction inlet of the compression device is arranged to receive refrigerant fluid from the gas outlet of the receiver.

An air conditioner includes an ejector that raises a pressure of refrigerant by using energy for refrigerant decompression and expansion. A switching mechanism switches between a refrigerant flow in a first operation and a refrigerant flow in a second operation. The air conditioner is configured such that in the first operation, refrigerant compressed by a compression mechanism radiates heat in a use-side heat exchanger and is decompressed and expanded by the ejector while refrigerant evaporated in a heat-source-side heat exchanger is raised in pressure by the ejector. The air conditioner is configured such that in the second operation, refrigerant compressed by the compression mechanism radiates heat in the heat-source-side heat exchanger and is decompressed and expanded by a first expansion valve before being evaporated in the use-side heat exchanger while refrigerant does not flow through the ejector.

A cooling system implements various processes to improve efficiency in high ambient temperatures. First, the system can flood one or more low side heat exchangers in the system. Second, the system can direct a portion of vapor refrigerant from a low side heat exchanger to a flash tank rather than to a compressor. Third, the system can transfer heat from refrigerant at a compressor suction to refrigerant at the discharge of a high side heat exchanger.