A method for operating a heat pump (20; 300) includes operating in a cooling mode wherein heat is absorbed by refrigerant in the indoor heat exchanger (26) and rejected by refrigerant in the outdoor heat exchanger (24). The heat pump switches to operation in a heating mode wherein heat is rejected by refrigerant in the indoor heat exchanger, heat is absorbed by refrigerant in the outdoor heat exchanger, and there is an ejector (60) motive flow and ejector secondary flow. In the heating mode a refrigerant pressure (PH) or temperature (TL) is measured and, responsive to the measured refrigerant pressure or temperature, at least one of a fan speed is changed and a needle (132) of the ejector is actuated.

A method for controlling ejector capacity in a vapour compression system (1) is disclosed. A parameter value being representative for a flow rate of liquid refrigerant from the evaporator(s) (8, 10) and into a return pipe (12, 13) is obtained, and the capacity of the ejector(s) (6) is adjusted based on the obtained parameter value. Ejector capacity may be shifted between low pressure ejectors (liquid ejectors) (6a, 6b, 6c, 6d) and high pressure ejectors (gas ejectors) (6e, 6f).

Refrigeration systems are described. The systems include a compression device, a heat rejecting heat exchanger, an ejector, and first and second expansion devices with respective heat absorbing heat exchangers. The ejector is arranged to receive refrigerant fluid from the heat rejecting heat exchanger at a high pressure inlet of the ejector. Fluid pathways extend from an outlet of the ejector into a branched flow path to provide flows of refrigerant from the ejector to the first and second expansion devices. The first heat absorbing heat exchanger provides cooling at a first temperature and refrigerant fluid from the outlet of the first heat absorbing heat exchanger is directed to a low pressure inlet of the ejector. The second heat absorbing heat exchanger provides cooling at a second temperature and refrigerant fluid from the outlet of the second heat absorbing heat exchanger is directed to the inlet of the compression device.

An ejector and a refrigeration system. The ejector includes: a high-pressure fluid passage, a flow valve for controlling a flow rate in the high-pressure fluid passage; a suction fluid passage; a mixing chamber, which includes a mixed fluid outlet; a thermal bulb disposed upstream of the flow valve, in the high-pressure fluid passage or outside the high-pressure fluid passage; and an elastic diaphragm disposed in the high-pressure fluid passage, wherein a closed cavity is on a first side of the diaphragm, and the high-pressure fluid passage is on a second side of the diaphragm; the thermal bulb in communication with the closed cavity, and the thermal bulb and the closed cavity are filled with fluid; and the diaphragm is associated with the flow valve so that an opening degree of the flow valve varies in response to a change in a pressure difference across two sides of the diaphragm.

A temperature chamber for conditioning air includes a temperature-insulated space which receives test material, and a temperature control device for controlling the temperature of the test space. The temperature control device allows a temperature in a range of −50° C. to +180° C. to be established within the space, and has a cooling device including a cooling circuit with a refrigerant, a heat exchanger, a compressor, a condenser, and an expansion element. A jet device is connected to a low-pressure side of the cooling circuit downstream of the heat exchanger and upstream of the compressor, a first bypass is connected to a high-pressure side of the cooling circuit downstream of the compressor, and the refrigerant is suppliable to the jet device from the high-pressure side via the first bypass as a driving fluid.

A thermal management system is described. The thermal management system includes an open circuit refrigeration circuit that has a refrigerant fluid flow path, with the refrigerant fluid flow path including a receiver configured to store a refrigerant fluid, an ejector having a primary flow inlet configured to receive refrigerant, a liquid separator, an evaporator configured to extract heat from a heat load that contacts the evaporator, with the evaporator coupled to the ejector and the liquid separator, and an exhaust line coupled to a vapor side outlet of the liquid separator. In operation, the evaporator in the open circuit refrigeration circuit would be coupled to a heat load.

A thermal management system is described. The thermal management system includes an open circuit refrigeration circuit that has a refrigerant fluid flow path, with the refrigerant fluid flow path including a receiver configured to store a refrigerant fluid, an ejector having a primary flow inlet configured to receive refrigerant, a liquid separator, an evaporator configured to extract heat from a heat load that contacts the evaporator, with the evaporator coupled to the ejector and the liquid separator, and an exhaust line coupled to a vapor side outlet of the liquid separator. In operation, the evaporator in the open circuit refrigeration circuit would be coupled to a heat load.

A thermal management system is described. The thermal management system includes an open circuit refrigeration circuit that has a refrigerant fluid flow path, with the refrigerant fluid flow path including a receiver configured to store a refrigerant fluid, an ejector having a primary flow inlet configured to receive refrigerant, a liquid separator, an evaporator configured to extract heat from a heat load that contacts the evaporator, with the evaporator coupled to the ejector and the liquid separator, and an exhaust line coupled to a vapor side outlet of the liquid separator. In operation, the evaporator in the open circuit refrigeration circuit would be coupled to a heat load.

A thermal management system that includes an open-circuit refrigeration system having an open-circuit refrigerant fluid flow path is described. The open-circuit refrigeration system includes a receiver configured to store a refrigerant fluid, an evaporator configured to receive the refrigerant fluid at a evaporator inlet and to extract heat from a heat load that contacts the evaporator, and provide refrigerant vapor at a evaporator outlet. The open-circuit refrigeration system also includes a vapor pump device having a vapor pump inlet that receives the refrigerant vapor and having a vapor pump outlet that outputs compressed refrigerant vapor to an exhaust line coupled to the vapor pump outlet, with the receiver, the evaporator, the vapor pump device, and the exhaust line connected in the open-circuit refrigerant fluid flow path.

A system has a compressor, a heat rejection heat exchanger, first and second ejectors, first and second heat absorption heat exchangers, and first and second separators. The heat rejection heat exchanger is coupled to the compressor to receive refrigerant compressed by the compressor. The first ejector has a primary inlet coupled to the heat rejection exchanger to receive refrigerant, a secondary inlet, and an outlet. The first separator has an inlet coupled to the outlet of the first ejector to receive refrigerant from the first ejector. The first separator has a gas outlet coupled to the compressor to return refrigerant to the compressor. The first separator has a liquid outlet coupled to the secondary inlet of the ejector to deliver refrigerant to the first ejector. The first heat absorption heat exchanger is coupled to the liquid outlet of the first separator to receive refrigerant and to the secondary inlet of the first ejector to deliver refrigerant to the first ejector. The second ejector has a primary inlet coupled to the liquid outlet of the first separator to receive refrigerant, a secondary inlet, and an outlet. The second separator has an inlet coupled to an outlet of the second ejector to receive refrigerant from the second ejector, a gas outlet coupled to the compressor to return refrigerant to the compressor, and a liquid outlet. The second heat absorption heat exchanger is coupled to the liquid outlet of the second separator to receive refrigerant and to the secondary inlet of the second ejector to deliver refrigerant to the second ejector.