Provided is a thermoacoustic refrigerator including an air column pipe, a prime mover, a load, and a heat accumulation tank. An exhaust gas supplied to and discharged from the heat accumulation tank is supplied, as a heat source, to the prime mover disposed inside the air column pipe, so as to cause self-oscillation of a working gas filled in the air column pipe so that sound waves are generated. With the sound waves, the load disposed inside the air column pipe converts sound wave energy into heat energy, so as to output cold heat.

The application relates to a cooling system, the cooling system having: an evaporator, a first compressor, a second compressor, a cooling component, an expansion device and a line system that connects the evaporator, the first compressor, the second compressor, the cooling component and the expansion device to one another. The cooling system includes a refrigerant, wherein the refrigerant comprises carbon dioxide. The first compressor and the second compressor are arranged in series with one another. The application also relates to a corresponding laboratory instrument.

A refrigeration apparatus uses R32 as a refrigerant, and includes a compressor, a condenser, an expansion mechanism, an evaporator and an accumulator. The accumulator is disposed in the suction flow path supplying refrigerant to the compressor. The accumulator has a casing that forms an inside space to separate the refrigerant into gas refrigerant and liquid refrigerant and accumulating surplus refrigerant, an inlet pipe feeding the refrigerant that has evaporated in the evaporator into the inside space, and an outlet pipe channeling the separated gas refrigerant to the compressor. A distal end opening in the inlet pipe of the accumulator is located in a height position separated by a dimension from a bottom of the inside space. The dimension is 0 to 0.3 times a height dimension of the inside space.

A hybrid air handler cooling unit has a bi-modal heat exchanger. In a direct expansion mode or a pumped refrigerant economization mode, the bi-modal heat exchanger is in a refrigerant path in parallel with first and second condenser coils and functions as a condenser coil. In a mixed direct expansion/pumped refrigerant economization mode, the bi-modal heat exchanger is in a refrigerant path in series between an outlet of a pump and an inlet of the first condenser coil and functions as a pre-cooler evaporator coil with return air first flowing across the bi-modal heat exchanger and then across an evaporator coil of an evaporator.

Provided is a thermoacoustic refrigerator including an air column pipe, a prime mover, a load, and a heat accumulation tank. An exhaust gas supplied to and discharged from the heat accumulation tank is supplied, as a heat source, to the prime mover disposed inside the air column pipe, so as to cause self-oscillation of a working gas filled in the air column pipe so that sound waves are generated. With the sound waves, the load disposed inside the air column pipe converts sound wave energy into heat energy, so as to output cold heat.

A multistage compression system uses refrigerant and oil. The multistage compression system includes a low-stage compressor that compresses the refrigerant, a high-stage compressor that further compresses the refrigerant compressed by the low-stage compressor, refrigerant pipes that introduce the refrigerant compressed and discharged by the low-stage compressor into a suction part of the high-stage compressor, an intercooler, and an oil discharge pipe. The intercooler cools the refrigerant discharged by the low-stage compressor before the refrigerant is sucked into the high-stage compressor. The intercooler is disposed between the refrigerant pipes. The oil discharge pipe discharges the oil in the low-stage compressor. The oil discharge pipe connects the low-stage compressor and a portion of the refrigerant pipes. The portion of the refrigerant pipes is on an upstream side of the intercooler.

A multistage compression system uses refrigerant and oil. The multistage compression system includes a low-stage compressor that compresses the refrigerant, a high-stage compressor that further compresses the refrigerant compressed by the low-stage compressor, refrigerant pipes that introduce the refrigerant compressed and discharged by the low-stage compressor into a suction part of the high-stage compressor, an intercooler, and an oil discharge pipe. The intercooler cools the refrigerant discharged by the low-stage compressor before the refrigerant is sucked into the high-stage compressor. The intercooler is disposed between the refrigerant pipes. The oil discharge pipe discharges the oil in the low-stage compressor. The oil discharge pipe connects the low-stage compressor and a portion of the refrigerant pipes. The portion of the refrigerant pipes is on an upstream side of the intercooler.

The present invention provides a pressure relief and recovery loop, a carbon dioxide refrigeration system and a control method thereof. The pressure relief and recovery loop includes: a gas storage reservoir (110), which is used for storing gas-phase carbon dioxide; a pressure relief flow passage (120), which is used for connecting the gas storage reservoir and an associated carbon dioxide refrigeration system, and is used for discharging the gas-phase carbon dioxide in the carbon dioxide refrigeration system into the gas storage reservoir; and a recovery flow passage (130), which is used for connecting the gas storage reservoir and the associated carbon dioxide refrigeration system, and on which a driving apparatus (131) is arranged, the recovery flow passage being used for recovering the gas-phase carbon dioxide in the gas storage reservoir into the carbon dioxide refrigeration system under the drive of the driving apparatus.

A pumped heat storage apparatus has a prime mover, a power take off, first and second fluid working machines functioning as a compressor (8) and as an expander (10), a working fluid circulation pathway with high and low pressure sides, and high and low temperature heat exchangers (18A-B). The heat exchangers operate using direct contact between gaseous working fluid and solid thermal storage media, such as glass beads, which move in opposite directions, typically using an augur (44). The system is reversible between energy storage and energy recovery modes and when it reverses, the direction of movement of the working fluid and the thermal storage media reverses. The apparatus may very rapidly swap between energy storage and energy recovery while having a high capacity and energy throughout.

A hybrid air handler cooling unit has a bi-modal heat exchanger. In a direct expansion mode or a pumped refrigerant economization mode, the bi-modal heat exchanger is in a refrigerant path in parallel with first and second condenser coils and functions as a condenser coil. In a mixed direct expansion/pumped refrigerant economization mode, the bi-modal heat exchanger is in a refrigerant path in series between an outlet of a pump and an inlet of the first condenser coil and functions as a pre-cooler evaporator coil with return air first flowing across the bi-modal heat exchanger and then across an evaporator coil of an evaporator.