A system includes a high side heat exchanger, a flash tank, a vessel, a load, and a compressor. The high side heat exchanger removes heat from a refrigerant. The flash tank stores the refrigerant from the high side heat exchanger. The vessel includes a chamber defined by an exterior housing and a tube positioned within the chamber. Heat is removed from the liquid refrigerant circulating through this tube and coming from the flash tank. The load uses the refrigerant from the tube to remove heat from a space proximate the load. The load sends the refrigerant into the chamber between the exterior housing and the tube. The compressor receives the refrigerant from the chamber between the exterior housing and the tube and compresses the refrigerant.

An energy recovery apparatus for use in a refrigeration system, comprises an intake port, a nozzle, a turbine and a discharge port. The intake port is adapted to be in fluid communication with a refrigerant cooler of a refrigeration system. The nozzle comprises a fluid passageway. The nozzle is configured to increase velocity of the refrigerant as it passes through the fluid passage -way. The turbine is positioned relative to the nozzle and configured to be driven by refrigerant discharged from the fluid passageway. The discharge port is downstream of the turbine and is configured to be in fluid communication with an evaporator of the refrigeration system.

Embodiments as disclosed herein are directed to a heat pump that employs at least two different refrigerants, each of which is optimized for either a cooling operation mode or a heating operation mode. The embodiments as disclosed herein can help increase the capacity and/or efficiency of a heat pump in both the cooling operation mode and the heating operation mode. In addition, the embodiments as disclosed herein may also eliminate the need for a ground source in a relatively low ambient temperature environment.

A defrost system includes: a cooling device in a freezer, and includes a casing, a heat exchanger pipe with a difference in elevation in the casing, and a drain receiver unit below the heat exchanger pipe; a refrigerating device to cool and liquefy CO.sub.2 refrigerant; and a refrigerant circuit for permitting the cooled and liquefied CO.sub.2 refrigerant to circulate to the heat exchanger pipe. The defrost system includes a bypass pipe of the heat exchanger pipe to form a CO.sub.2 circulation path; an on-off valve in the heat exchanger pipe to be closed during defrosting so that the CO.sub.2 circulation path is a closed circuit; a pressure adjusting unit for adjusting pressure of the CO.sub.2 refrigerant during defrosting; and a brine circuit as a first heating medium, in which the defrost system permits the CO.sub.2 refrigerant to naturally circulate in the closed circuit during defrosting by a thermosiphon effect.

A heat exchange device has a heat transfer member having thermal conductivity and a fin that is provided integrally with the heat transfer member. A heat transfer is performed between the heat transfer member and the fin. The fin is configured by more than one of a carbon nanotube aggregate that is configured by carbon nanotubes assembled together. The carbon nanotube aggregates are arranged on the heat transfer member and distanced from each other, and protrude from the heat transfer member in an axial direction of the carbon nanotubes.

Methods and systems for providing control of a heat pump of a motor vehicle are presented. In one operating mode, speed of a heat pump compressor is controlled responsive to an outlet pressure of the heat pump compressor. In a second operating mode, speed of the heat pump compressor is controlled responsive to a pressure ratio between an inlet and an outlet of the heat pump compressor.

A motor vehicle may have a cylindrical component having two grooves aligned orthogonally to a cylinder axis, recessed into local areas of a lateral surface, and running parallel to each other, and a blind hole in an end of the cylindrical component. A fastening component for the cylindrical component may include a holding device having a U-shaped socket and a head portion having a through opening. The holding device may be matched to the cylindrical component in such a way that the cylindrical component is positively insertable via the two grooves into the U-shaped socket until the blind hole in the end is in alignment with the through opening in the head portion of the holding device. The fastening arrangement may also have a fastening element that is insertable and screwable through the through opening in the head portion into the blind hole in the cylindrical component.

An electrochemical compressor utilizes an anion conducting layer disposed between an anode and a cathode for transporting a working fluid. The working fluid may include carbon dioxide that is dissolved in water and is partially converted to carbonic acid that is equilibrium with bicarbonate anion. An electrical potential across the anode and cathode creates a pH gradient that drives the bicarbonate anion across the anion conducting layer to the cathode, wherein it is reformed into carbon dioxide. Therefore, carbon dioxide is pumped across the anion conducting layer. The compressor may be part of a refrigeration system that pumps the working fluid in a closed loop through a condenser and an evaporator.

A system includes a high side heat exchanger, a flash tank, a first load, a second load, and a thermal storage tank. The high side heat exchanger is configured to remove heat from a refrigerant. The flash tank is configured to store the refrigerant from the high side heat exchanger and discharge a flash gas. The first load is configured to use the refrigerant from the flash tank to remove heat from a first space proximate to the first load. The second load is configured to use the refrigerant from the flash tank to remove heat from a second space proximate to the second load. The thermal storage tank is configured, when a power outage is determined to be occurring, to receive the flash gas from the flash tank, and remove heat from the flash gas.

Method for regulation of a single-valve CO.sub.2 refrigerating apparatus including: an operation A of detecting, over time, the value of a primary parameter and the value of a secondary parameter, wherein said primary parameter is chosen from said high pressure HP and said superheat temperature Tsh, wherein said secondary parameter is said superheat temperature Tsh if said primary parameter is said high pressure HP or is said high pressure HP if said primary parameter is said superheat temperature Tsh; a primary regulation operation B, which involves regulation of said expansion valve (13) so that the value of said primary parameter tends towards a set-point value; an operation C of estimating an optimal value Vo for said secondary parameter; and a secondary regulation operation D which involves varying said set-point value from an optimal set-point value or from a current value if the value of said secondary parameter does not fall within a predefined tolerance range.