Abstract: A refrigeration system includes a compressor for compressing a refrigerant, a condenser for cooling the refrigerant, an evaporator for heating the refrigerant, and a lubrication system for providing a lubricant mist to a movable component of the compressor. The lubrication system includes an ejector arranged in fluid communication with the compressor and the evaporator, wherein the lubricant mist is carried by the refrigerant to the movable component.

Abstract: A mixing device and a vapor compression system incorporating a mixing device are provided. The vapor compression system includes a suction line, at least two compressors, and at least one mixing device that is predominantly open (e.g., i.e., include at least a certain percentage, such as seventy percent (70%), of voids/openings). The suction line is used for transferring a working fluid made up of a mixture of a refrigerant and an oil. The suction line includes at least one inlet (e.g., for receiving the working fluid) and at least one outlet (e.g., for distributing the working fluid). The vapor compression system include a first compressor fluidly connected to a first outlet and a second compressor fluidly connected to a second outlet. At least one mixing device is disposed within the suction line (e.g., to increase an internal turbulence of the working fluid).

Abstract: A heat exchange tube segment for use in a heat exchange includes a fabricated tube body having an upper surface, a lower surface, a leading edge, a trailing edge, and a plurality of fluidly distinct flow channels formed therein. The fabricated tube body has a length, width, height, and a total tube cross-sectional area measured between the upper surface, the lower surface, the leading edge, and the trailing edge. A ratio of the width to the height of the fabricated tube body is between about 10 and 20 and a ratio of the width to a number of the plurality of fluidly distinct flow channels is between 1 and 2.5. Each of the plurality of fluidly distinct flow channels forms an open area in a cross-section of the fabricated tube body, and a ratio of the open area to the total tube cross-sectional area is between 0.3 and 0.44.

Abstract: A system includes a compressor for increasing the pressure of a refrigerant; a condenser heat exchanger arranged downstream of the compressor for receiving a high pressure refrigerant output from the compressor and for transferring heat from the high pressure refrigerant to a source of water; an expansion device for reducing the pressure of a refrigerant; and an evaporator heat exchanger for extracting heat from ambient air. The evaporator heat exchanger includes a first tube bank having a first inlet arranged to receive a high pressure refrigerant output from the condenser and a first outlet fluidly coupled to the expansion device; and a second tube bank having a second inlet arranged to receive a low pressure refrigerant output from the expansion device, and a second outlet fluidly coupled to an inlet of the compressor.

Abstract: A heat pump system includes a compression device 12, a heat rejecting heat exchanger 14, an expansion device 18 and a heat absorbing heat exchanger 16; wherein the expansion device 18 provides a controllable degree of expansion. The heat pump system is operated in accordance with a method including determining a temperature indicative of frosting conditions on an exterior surface of the heat absorbing heat exchanger 16; operating the heat pump system in a first mode if the temperature indicative of frosting conditions is above a threshold value, and operating the heat pump system in a second mode if the temperature indicative of frosting conditions is within a range of temperatures that is below the threshold value.

Abstract: A refrigeration system includes a main refrigeration circuit for holding refrigerant fluid, the main refrigeration circuit including: a compression device 12, a heat rejecting heat exchanger 14, an expansion device 18 and a heat absorbing heat exchanger 16. In addition, the refrigeration system includes a buffer tank 20 attached to the main refrigeration circuit, with valves 22, 24 for controlling flow of refrigerant fluid between the main refrigeration circuit and the buffer tank 20. The refrigeration system is arranged such that the valves 22, 24 are controlled to transfer refrigerant fluid between the main refrigeration circuit and the buffer tank 20 based on a measure of sub-cooling in the main refrigeration circuit.

Abstract: A method of manufacturing a suction pipe for a multi-compressor device having a plurality of inlets, the suction pipe comprising a primary portion and a plurality of secondary portions arranged to receive fluid from the primary portion for supplying fluid in parallel to the inlets of a multi-compressor device. The method includes designing the suction pipe by: selecting a first dimension for the primary portion of the suction pipe, calculating a first fluid velocity for fluid in the primary portion based on the first dimension, and comparing the first fluid velocity to a first predetermined threshold; selecting a second dimension for the secondary portions, calculating a second fluid velocity for fluid in the secondary portions based on the second dimension, and comparing the second fluid velocity to a second predetermined threshold; and calculating a ratio of the first fluid velocity to the second fluid velocity.

Abstract: A mixing device and a vapor compression system incorporating a mixing device are provided. The vapor compression system includes a suction line, at least two compressors, and at least one mixing device that is predominantly open (e.g., i.e., include at least a certain percentage, such as seventy percent (70%), of voids/openings). The suction line is used for transferring a working fluid made up of a mixture of a refrigerant and an oil. The suction line includes at least one inlet (e.g., for receiving the working fluid) and at least one outlet (e.g., for distributing the working fluid). The vapor compression system include a first compressor fluidly connected to a first outlet and a second compressor fluidly connected to a second outlet. At least one mixing device is disposed within the suction line (e.g., to increase an internal turbulence of the working fluid).

Abstract: A refrigeration system includes a compressor for compressing a refrigerant, a condenser for cooling the refrigerant, an evaporator for heating the refrigerant, and a lubrication system for providing a lubricant mist to a movable component of the compressor. The lubrication system includes an ejector arranged in fluid communication with the compressor and the evaporator, wherein the lubricant mist is carried by the refrigerant to the movable component.

Abstract: A heat pump system includes a compression device 12, a heat rejecting heat exchanger 14, an expansion device 18 and a heat absorbing heat exchanger 16; wherein the expansion device 18 provides a controllable degree of expansion. The heat pump system is operated in accordance with a method including determining a temperature indicative of frosting conditions on an exterior surface of the heat absorbing heat exchanger 16; operating the heat pump system in a first mode if the temperature indicative of frosting conditions is above a threshold value, and operating the heat pump system in a second mode if the temperature indicative of frosting conditions is within a range of temperatures that is below the threshold value.

Abstract: Refrigeration systems are described. The systems include a refrigeration circuit having a compression device, a heat rejecting heat exchanger, an expansion device, and a heat absorbing heat exchanger. The refrigeration systems include one or more sensors configured to measure a pressure associated with the heat rejecting heat exchanger, and a controller configured to compare the pressure measured by the one or more sensors to a predicted pressure, and to control the expansion device on the basis of the comparison.

Abstract: A method of manufacturing a suction pipe for a multi-compressor device having a plurality of inlets, the suction pipe comprising a primary portion and a plurality of secondary portions arranged to receive fluid from the primary portion for supplying fluid in parallel to the inlets of a multi-compressor device. The method includes designing the suction pipe by: selecting a first dimension for the primary portion of the suction pipe, calculating a first fluid velocity for fluid in the primary portion based on the first dimension, and comparing the first fluid velocity to a first predetermined threshold; selecting a second dimension for the secondary portions, calculating a second fluid velocity for fluid in the secondary portions based on the second dimension, and comparing the second fluid velocity to a second predetermined threshold; and calculating a ratio of the first fluid velocity to the second fluid velocity.

Abstract: Compressor systems for compression of refrigerant fluid are described. The compressor systems include first and second compressor elements each having a housing. An equalization line fluidly connects the first and second housings at suction sides in order to allow for equalization of pressure between the housings as well as flow of lubricant between the housings. An equalization valve on the equalization line is used to open and close the connection between the first and second compressor element housings. The compressor system is arranged for full load operation using both the first and second compressor elements as well as for part load operation in which one of the compressor elements is not utilized. The equalization valve is opened during full load operation and is closed during part load operation to thereby prevent movement of lubricant and/or refrigerant fluid between the first and second compressor element housings during part load operation.

Abstract: A refrigeration system includes a main refrigeration circuit for holding refrigerant fluid, the main refrigeration circuit including: a compression device 12, a heat rejecting heat exchanger 14, an expansion device 18 and a heat absorbing heat exchanger 16. In addition, the refrigeration system includes a buffer tank 20 attached to the main refrigeration circuit, with valves 22, 24 for controlling flow of refrigerant fluid between the main refrigeration circuit and the buffer tank 20. The refrigeration system is arranged such that the valves 22, 24 are controlled to transfer refrigerant fluid between the main refrigeration circuit and the buffer tank 20 based on a measure of sub-cooling in the main refrigeration circuit.