A compressor suction pipe includes a bent portion at least including a first pipe segment on the most upstream side with respect to flow of a fluid to be compressed, a second pipe segment connected to a suction side of a compressor and extending in a direction different from the extension direction of the first pipe segment, and a third pipe segment disposed between the first pipe segment and the second pipe segment and extending in a direction different from the extension directions of the first and second pipe segments, and at least one partition extending at least from an intermediate portion of the first pipe segment at least to an intermediate portion of the second pipe segment in the bent portion and dividing an interior of the bent portion. The partition extends in a direction intersecting a virtual plane including an incircle that touches an axis of the first pipe segment on an upstream side of a downstream end of the first pipe segment and touches an axis of the second pipe segment.

A heat exchanger unit includes: a first heat exchanger including a first header, a second header, and a first flat pipe group that includes first flat multi-hole pipes connected to each of the first header and the second header; and a second heat exchanger: disposed in parallel with the first heat exchanger on an air downstream side, from the first heat exchanger, of air flow generated by a fan; and including a third header, a fourth header, and a second flat pipe group that includes second flat multi-hole pipes connected to each of the third header and the fourth header. The fourth header causes a refrigerant that flows in from the third header to flow out to the first header.

A heating, ventilation, air conditioning, and/or refrigeration (HVAC&R) system includes a refrigerant circuit configured to flow a refrigerant therethrough, a sump configured to direct a lubricant to a compressor, an ejector configured to direct the lubricant from the refrigerant circuit to the sump, and an expansion device configured to reduce a pressure of the refrigerant directed through the refrigerant circuit. The HVAC&R system further includes a controller configured to instruct the expansion device to adjust to a first position to enable the ejector to direct lubricant from the refrigerant circuit to the sump at a first target flow rate in a first mode, and the controller is configured to instruct the expansion device to adjust to a second position to enable the ejector to direct lubricant from the refrigerant circuit to the sump at a second target flow rate in a second mode.

Methods, systems, and apparatuses are described to help manage oil return such as in a chiller system of a HVAC system. A refrigerant/oil mixture can be directed out of the evaporator into an oil return heat exchanger that is configured to help vaporize a refrigerant portion of the refrigerant/oil mixture. Superheat refrigerant vapor can be directed from a condenser into the oil return heat exchanger as the heat energy to vaporize the refrigerant portion in the refrigerant/oil mixture. The oil return heat exchanger can be positioned lower than the evaporator so that gravity can help the refrigerant/oil mixture to flow into the oil return heat exchanger.

Provided are a separator with improved oil separation efficiency, and a refrigeration cycle apparatus including the separator. The separator includes an inflow pipe portion, an oil storage portion, an oil return pipe portion, and an outflow pipe portion. The inflow pipe portion includes a swirling portion that defines a flow direction of refrigerant so as to swirl the refrigerant. The oil storage portion is connected to the inflow pipe portion. The oil return pipe portion is connected to a vertically lower side of the oil storage portion. The outflow pipe portion includes an opening end that faces the swirling portion. The outflow pipe portion extends from a region that faces the swirling portion to the outside of the oil storage portion. The opening end is configured such that the refrigerant discharged from the swirling portion can directly flow thereinto.

An apparatus includes a first expander, a first load, a first work recovery compressor, a valve, and a first compressor. The first expander expands a refrigerant. The first load uses the refrigerant to cool a space proximate the first load. The work recovery compressor compresses the refrigerant from the first load and is driven by the first expander. The valve reduces the pressure of the refrigerant from the work recovery compressor. The first compressor compresses the refrigerant from the valve.

An air conditioner is provided. The air conditioner may include a compressor to compress a refrigerant, at least one oil sensor disposed in the compressor to detect oil stored in the compressor, an oil separator to separate the oil from the refrigerant discharged from the compressor, a first collection tube to collect the oil separated by the oil separator into the compressor, a second collection tube disposed at a height different from a height of the first collection tube, an oil valve disposed in the second collection tube, and a controller to control the oil valve on the basis of information detected by the oil sensor.

A composition for a heat cycle system having less influence over the ozone layer, a low global warming potential, and excellent stability and durability is provided. A heat cycle system using the composition is also provided. The composition contains a working fluid and a phosphoric acid ester. The working fluid contains trifluoroethylene and difluoromethane. An interaction distance (Ra) between the working fluid and the phosphoric acid ester as determined from the Hansen solubility parameters is at most 15.

In a compressor for refrigerant having a suction inlet for refrigerant and a pressure outlet for compressed refrigerant, said compressor comprising a compression unit and an electric motor driving said compression unit, said electric motor being a synchronous reluctance motor having a stator and a rotor, said rotor comprising a plurality of stacked disc elements, each disc element having a plurality of flux barriers configured to give the rotor core an anisotropic magnetic structure and formed as apertures in said disc element, it is provided that said flux barriers are arranged in said rotor core to define channels enabling a flow of refrigerant through said rotor core, said rotor is provided with a first support element acting on a first front side of said rotor core and a second support element acting on a second front side of said rotor core, said support elements being provided with cut-out sections and said cut-out sections being designed to uncover at least 70% of the cross section of apertures defined by said flux barriers in the respective disc element forming the respective front side of said rotor core.

A refrigeration apparatus, including a main circuit for a loop circulation of a main flow of refrigerant, the main circuit including a compressor, a condenser, an expansion valve and an evaporator. The refrigeration apparatus comprises a lubrication branch, for deriving a lubrication flow from the main flow for feeding the compressor for lubrication. The main circuit includes a low-temperature part, consisting in the evaporator, the compressor inlet, and any part of the main circuit between the evaporator and the compressor inlet. The lubrication branch further includes a subcooling heat exchanger, which is configured for enabling an exchange of heat between the lubrication flow circulating through the lubrication branch and the main flow of refrigerant circulating through the low-temperature part, so that the lubrication flow may be cooled by the main flow of refrigerant circulating through the low-temperature part, within the subcooling heat exchanger.