EP4006443A1 - Kühlvorrichtung - Google Patents

Kühlvorrichtung Download PDF

Info

Publication number
EP4006443A1
EP4006443A1 EP21209825.5A EP21209825A EP4006443A1 EP 4006443 A1 EP4006443 A1 EP 4006443A1 EP 21209825 A EP21209825 A EP 21209825A EP 4006443 A1 EP4006443 A1 EP 4006443A1
Authority
EP
European Patent Office
Prior art keywords
refrigerant
flow channel
compression mechanism
gas
refrigeration apparatus
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP21209825.5A
Other languages
English (en)
French (fr)
Inventor
Yuichi MURASHIMA
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Panasonic Intellectual Property Management Co Ltd
Original Assignee
Panasonic Intellectual Property Management Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Panasonic Intellectual Property Management Co Ltd filed Critical Panasonic Intellectual Property Management Co Ltd
Publication of EP4006443A1 publication Critical patent/EP4006443A1/de
Withdrawn legal-status Critical Current

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B1/00—Compression machines, plants or systems with non-reversible cycle
    • F25B1/10—Compression machines, plants or systems with non-reversible cycle with multi-stage compression
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B9/00—Compression machines, plants or systems, in which the refrigerant is air or other gas of low boiling point
    • F25B9/002—Compression machines, plants or systems, in which the refrigerant is air or other gas of low boiling point characterised by the refrigerant
    • F25B9/008—Compression machines, plants or systems, in which the refrigerant is air or other gas of low boiling point characterised by the refrigerant the refrigerant being carbon dioxide
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B41/00—Fluid-circulation arrangements
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B49/00—Arrangement or mounting of control or safety devices
    • F25B49/02—Arrangement or mounting of control or safety devices for compression type machines, plants or systems
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B9/00—Compression machines, plants or systems, in which the refrigerant is air or other gas of low boiling point
    • F25B9/08—Compression machines, plants or systems, in which the refrigerant is air or other gas of low boiling point using ejectors
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2309/00—Gas cycle refrigeration machines
    • F25B2309/06—Compression machines, plants or systems characterised by the refrigerant being carbon dioxide
    • F25B2309/061—Compression machines, plants or systems characterised by the refrigerant being carbon dioxide with cycle highest pressure above the supercritical pressure
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2341/00—Details of ejectors not being used as compression device; Details of flow restrictors or expansion valves
    • F25B2341/001—Ejectors not being used as compression device
    • F25B2341/0012—Ejectors with the cooled primary flow at high pressure
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2400/00—General features or devices for refrigeration machines, plants or systems, combined heating and refrigeration systems or heat-pump systems, i.e. not limited to a particular subgroup of F25B
    • F25B2400/05—Compression system with heat exchange between particular parts of the system
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2400/00—General features or devices for refrigeration machines, plants or systems, combined heating and refrigeration systems or heat-pump systems, i.e. not limited to a particular subgroup of F25B
    • F25B2400/07—Details of compressors or related parts
    • F25B2400/072—Intercoolers therefor
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2400/00—General features or devices for refrigeration machines, plants or systems, combined heating and refrigeration systems or heat-pump systems, i.e. not limited to a particular subgroup of F25B
    • F25B2400/07—Details of compressors or related parts
    • F25B2400/075—Details of compressors or related parts with parallel compressors
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2400/00—General features or devices for refrigeration machines, plants or systems, combined heating and refrigeration systems or heat-pump systems, i.e. not limited to a particular subgroup of F25B
    • F25B2400/13—Economisers
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2400/00—General features or devices for refrigeration machines, plants or systems, combined heating and refrigeration systems or heat-pump systems, i.e. not limited to a particular subgroup of F25B
    • F25B2400/23—Separators
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2700/00—Sensing or detecting of parameters; Sensors therefor
    • F25B2700/19—Pressures
    • F25B2700/193—Pressures of the compressor
    • F25B2700/1933—Suction pressures
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2700/00—Sensing or detecting of parameters; Sensors therefor
    • F25B2700/19—Pressures
    • F25B2700/195—Pressures of the condenser
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2700/00—Sensing or detecting of parameters; Sensors therefor
    • F25B2700/21—Temperatures
    • F25B2700/2106—Temperatures of fresh outdoor air

Definitions

  • the present disclosure relates to a refrigeration apparatus in which a refrigerant containing carbon dioxide circulates.
  • a refrigeration apparatus includes a refrigeration cycle formed from a compression section, a gas cooler, a throttle section, an evaporator, and the like.
  • a refrigerant compressed in the compression section radiates heat in the gas cooler, and is then decompressed in the throttle section and evaporates in the evaporator. As the refrigerant evaporates, the surrounding air is cooled.
  • An object of the present disclosure is to improve the performance of a refrigeration apparatus which uses a refrigerant containing carbon dioxide and utilizes an ejector.
  • a refrigeration apparatus includes a main compression mechanism, a gas cooler, a main throttle mechanism, and an evaporator, and allows circulation of a refrigerant containing carbon dioxide.
  • the refrigeration apparatus includes a split heat exchanger including a first flow channel and a second flow channel, in which the first flow channel is disposed at a site downstream of the gas cooler and upstream of the main throttle mechanism, and part of a refrigerant flowing out of the first flow channel flows into the second flow channel; an auxiliary throttle mechanism that throttles a refrigerant that is to flow into the second flow channel; and an ejector including a nozzle and a suction part, in which the nozzle is disposed at a site downstream of the main compression mechanism and upstream of the first flow channel, and the suction part sucks in a refrigerant flowing out of the second flow channel.
  • the present disclosure is capable of improving the performance of a refrigeration apparatus which uses a refrigerant containing carbon dioxide and uses an ejector.
  • FIG. 1 illustrates a refrigerant circuit of refrigeration apparatus 1 according to Embodiment 1.
  • Refrigeration apparatus 1 includes refrigerator unit 2 installed in, for example, an indoor machine room or an outdoor environment, and load device 3, for example, a showcase installed in a supermarket or the like.
  • Refrigerator unit 2 and load device 3 are connected with each other by refrigerant pipe (liquid pipe) 31 and refrigerant pipe 32 via unit outlet 2 out and unit inlet 2in to form predetermined refrigerant circuit 4.
  • Load device 3 may be a cooling coil of a food warehouse or the like, or a cooling device for cooling a refrigerant such as water.
  • Carbon dioxide (R744) whose pressure on the high pressure side may become equal to or higher than the critical pressure (supercritical), circulates as a refrigerant in refrigerant circuit 4.
  • the refrigerant may consist only of carbon dioxide, or may be a mixed refrigerant containing carbon dioxide and other substances.
  • the mixed refrigerant may contain carbon dioxide and, for example, one or more of R32, R41, R134a, R125, R152a, propane and dimethyl ether. Each arrow shown in FIG. 1 indicates the flow of a refrigerant.
  • the lubricating oil that circulates in refrigerant circuit 4 together with the refrigerant is, for example, mineral oil, alkylbenzene oil, ether oil, ester oil, or PAG (polyalkyl glycol).
  • Refrigerant circuit 4 includes main compression mechanism 11, gas cooler 12, ejector 13, split heat exchanger 14, and auxiliary throttle mechanism 15 in refrigerator unit 2.
  • Refrigerant circuit 4 includes main throttle mechanism 16 and evaporator 17 in load device 3.
  • Main compression mechanism 11 which is a frequency-variable compressor, has one or more compression mechanism parts, sucks a refrigerant in a gas-phase (i.e., gas-phase refrigerant), and discharges the refrigerant having a high temperature and high pressure.
  • gas-phase i.e., gas-phase refrigerant
  • the refrigerant discharged from main compression mechanism 11 passes through pipe 21 to flow into gas cooler 12.
  • Gas cooler 12 lowers the temperature of the refrigerant by exchanging heat between the refrigerant and the outside air supplied by a blower for the gas cooler (not illustrated). Alternatively, gas cooler 12 may exchange heat between the refrigerant and water supplied by a water pump for the gas cooler.
  • Nozzle 131 is configured in such a way that the opening degree thereof can be adjusted.
  • the opening degree of nozzle 131 increases, the flow velocity of the refrigerant, which flows in from nozzle 131 and passes through ejector 13, decreases, and when the opening degree decreases, the flow velocity of the refrigerant increases.
  • the refrigerant flowing into nozzle 131 expands while mixing with a gas-phase refrigerant sucked in from suction part 132 (which will be described below) and flows out of ejector 13 in a gas-liquid mixed state.
  • suction part 132 which will be described below
  • the static pressure in ejector 13 decreases, so that the suction pressure in suction part 132 decreases (suction becomes easier).
  • the static pressure in ejector 13 increases, so that the suction pressure in suction part 132 increases (suction becomes more difficult).
  • the refrigerant flowing out of ejector 13 passes through pipe 23 to flow into first flow channel 141 of split heat exchanger 14.
  • the refrigerant flowing into first flow channel 141 flows out of first flow channel 141 with the temperature of the refrigerant lowered by exchanging heat with a refrigerant that flows through second flow channel 142 (which will be described below).
  • Main throttle mechanism 16 is, for example, an electric expansion valve whose opening degree can be adjusted.
  • auxiliary throttle mechanism 15 is, for example, an electric expansion valve whose opening degree can be adjusted.
  • Auxiliary throttle mechanism 15 expands and vaporizes the refrigerant flowing into auxiliary throttle mechanism 15. The temperature of the refrigerant is lowered during the procedure.
  • auxiliary throttle mechanism 15 The refrigerant flowing out of auxiliary throttle mechanism 15 is in a gas-liquid mixed state, and passes through pipe 27 to flow into second flow channel 142 of split heat exchanger 14.
  • the refrigerant flowing into second flow channel 142 exchanges heat with a refrigerant passing through first flow channel 141 to lower the temperature of the refrigerant passing through first flow channel 141 as described above, and then flows out of second flow channel 142.
  • the refrigerant flowing out of second flow channel 142 passes through pipe 28 and is sucked into suction part 132 of ejector 13.
  • the refrigerant sucked into ejector 13 from suction part 132 mixes with a refrigerant sucked from nozzle 131.
  • main throttle mechanism 16 which is, for example, an electric expansion valve.
  • the refrigerant flowing out of main throttle mechanism 16 flows into evaporator 17 via refrigerant pipe 33, and is completely evaporated in evaporator 17.
  • the refrigerant flowing through evaporator 17 exchanges heat with a fluid in load device 3, for example, air, and cools the air.
  • the fluid in load device 3 may be another refrigerant (for example, water), which is to be cooled by the refrigerant circulating in refrigerant circuit 4.
  • the refrigerant flowing out of evaporator 17 passes through refrigerant pipe 32, unit inlet 2in and pipe 29, and is sucked into main compression mechanism 11.
  • Refrigerator unit 2 includes control device 50 that controls the entire refrigeration apparatus 1.
  • Low pressure sensor 51 (herein also referred to as “third pressure sensor”), which detects the pressure (low pressure) of the refrigerant to be sucked into main compression mechanism 11, is attached at a site downstream of main throttle mechanism 16 and upstream of main compression mechanism 11, for example, at pipe 29. A value detected by low pressure sensor 51 is transmitted to control device 50.
  • the value detected by low pressure sensor 51 indicates the evaporation pressure of a refrigerant in evaporator 17, that is, the temperature of the refrigerant in evaporator 17.
  • Control device 50 can adjust the temperature of the refrigerant in evaporator 17 and thus the temperature of a fluid in load device 3 by adjusting the operating frequency of main compression mechanism 11 based on the detection result from low pressure sensor 51. In other words, control device 50 can cause main compression mechanism 11 to perform an operation according to the refrigeration capacity required in load device 3.
  • the carbon dioxide-containing refrigerant can generate a fluid of desired temperature and quantity in evaporator 17 by repeating the above described cycle.
  • the refrigeration apparatus 1 includes ejector 13, split heat exchanger 14, and auxiliary throttle mechanism 15 as described above.
  • Ejector 13 can expand a refrigerant that has become in a high pressure state without requiring power.
  • Split heat exchanger 14 and auxiliary throttle mechanism 15 can lower the temperature of a refrigerant that has flowed out of ejector 13 before the refrigerant flows into main throttle mechanism 16.
  • Main throttle mechanism 16 can expand the refrigerant having passed through split heat exchanger 14 to lower its temperature.
  • refrigeration apparatus 1 is capable of adjusting the pressure on the high-pressure side (discharge side of main compression mechanism 11) while obtaining a desired refrigeration capacity in load device 3 by virtue of the presence of ejector 13, split heat exchanger 14, and auxiliary throttle mechanism 15 in the refrigeration apparatus. That is, refrigeration apparatus 1 can appropriately operate main compression mechanism 11 according to the temperature of the outside air or water supplied to gas cooler 12.
  • ejector 13 is disposed between gas cooler 12 and first flow channel 141 of split heat exchanger 14.
  • ejector 13 may be disposed at any site downstream of main compression mechanism 11 and upstream of first flow channel 141.
  • ejector 13 may be disposed at a site downstream of main compression mechanism 11 and upstream of gas cooler 12. This disposition allows for efficient generation of cooled fluid (e.g., air or water) of desired temperature and quantity, in addition to the effects described above.
  • cooled fluid e.g., air or water
  • FIG. 2 illustrates a refrigerant circuit of refrigeration apparatus 1 according to Embodiment 2.
  • the description of matters common to Embodiment 1 may be omitted. Conversely, the description for the present embodiment may apply to Embodiment 1.
  • Refrigeration apparatus 1 includes gas-liquid separator 18, auxiliary compression mechanism 19, and a transfer pressure sensor 52 (herein also referred to as "first pressure sensor").
  • first pressure sensor a transfer pressure sensor 52
  • pipe 23 connecting ejector 13 with first flow channel 141 of split heat exchanger 14 is divided into pipe 231 on the upstream side and pipe 232 on the downstream side, and gas-liquid separator 18 is disposed between these pipes.
  • Gas-liquid separator 18 is a tank capable of storing a refrigerant.
  • a refrigerant in a gas-liquid mixed state flows into gas-liquid separator 18 via the inlet connected to pipe 231.
  • the refrigerant that has flowed into gas-liquid separator 18 is separated into a gas-phase refrigerant and a liquid-phase refrigerant.
  • the liquid-phase refrigerant separated in gas-liquid separator 18 flows out from the liquid-phase refrigerant outlet of gas-liquid separator 18 connected to pipe 232 and flows into first flow channel 141 of split heat exchanger 14.
  • the gas-phase refrigerant separated in gas-liquid separator 18 flows out from the gas-phase refrigerant outlet of gas-liquid separator 18 connected to pipe 41.
  • the gas-phase refrigerant flowing out of the gas-phase refrigerant outlet passes through pipe 41 and is sucked into auxiliary compression mechanism 19.
  • Transfer pressure sensor 52 is disposed at pipe 41. Transfer pressure sensor 52 detects the pressure of a refrigerant that is to flow into main throttle mechanism 16. A value detected by transfer pressure sensor 52 is transmitted to control device 50.
  • Transfer pressure sensor 52 may be disposed at any site other than pipe 41 when the transfer pressure sensor 52 can detect the pressure of the refrigerant that is to flow into main throttle mechanism 16. Transfer pressure sensor 52 may be disposed, for example, at pipe 231, gas-liquid separator 18, pipe 232, first flow channel 141, pipe 24, branch part 25, branch pipe 26, or refrigerant pipe 31.
  • Auxiliary compression mechanism 19 is, for example, a compressor including an airtight container, an electric element that serves as a drive element housed in internal space of the airtight container, and a rotary compression element driven by a rotating shaft of the electric element.
  • a refrigerant compressed by auxiliary compression mechanism 19 is discharged to merging pipe 42.
  • Merging pipe 42 is connected to pipe 21 at merging part 43 that is provided between the ends of pipe 21, downstream of main compression mechanism 11 and upstream of gas cooler 12.
  • the refrigerant discharged to merging pipe 42 from auxiliary compression mechanism 19 passes through merging pipe 42 and merging part 43 to join a refrigerant in pipe 21 discharged from main compression mechanism 11.
  • Refrigeration apparatus 1 includes high pressure sensor 53 (herein also referred to as “second pressure sensor”) and outside air temperature sensor 54 (herein also referred to as “first temperature sensor”). Values detected by those sensors are transmitted to control device 50.
  • High pressure sensor 53 detects the pressure (high pressure) of a refrigerant discharged from main compression mechanism 11, and may be disposed anywhere, in so far as the high pressure sensor can detect this pressure. In the present embodiment, high pressure sensor 53 is disposed at pipe 22, but may be disposed at pipe 21 or at gas cooler 12.
  • Outside air temperature sensor 54 detects the outside air temperature, that is, the temperature of a fluid, for cooling the refrigerant, in gas cooler 12. Outside air temperature sensor 54 is disposed, for example, in the vicinity of gas cooler 12. Gas cooler 12 is not necessarily limited to a cooler that cools a refrigerant with outside air, and may be, for example, a cooler that cools the refrigerant with water. In this case, the first temperature sensor is a water temperature sensor in place of outside air temperature sensor 54.
  • Refrigeration apparatus 1 includes transfer temperature sensor 55 (herein also referred to as “second temperature sensor”) and second flow channel inlet temperature sensor 56 (herein also referred to as “third temperature sensor”). Values detected by those sensors are transmitted to control device 50.
  • second temperature sensor transfer temperature sensor 55
  • second flow channel inlet temperature sensor 56 herein also referred to as “third temperature sensor”
  • Transfer temperature sensor 55 detects the temperature of a refrigerant to be supplied to main throttle mechanism 16, and may be disposed anywhere, in so far as the transfer temperature sensor can detect this temperature. In the present embodiment, transfer temperature sensor 55 is disposed at pipe 24, but may be disposed at branch part 25 or branch pipe 26, or may be disposed at refrigerant pipe 31.
  • Second flow channel inlet temperature sensor 56 detects the temperature of a refrigerant that is to flow into second flow channel 142 of split heat exchanger 14, and is disposed at pipe 27.
  • a refrigerant circulates as follows.
  • Main compression mechanism 11 sucks a refrigerant in a gas-phase state and discharges the refrigerant in a high pressure state.
  • the refrigerant discharged from main compression mechanism 11 passes through pipe 21 to flow into gas cooler 12.
  • the refrigerant whose temperature is lowered in the gas cooler passes through pipe 22 to flow into nozzle 131 of ejector 13.
  • the refrigerant flowing into nozzle 131 expands while mixing with a gas-phase refrigerant sucked in from suction part 132 and flows out of ejector 13 in a gas-liquid mixed state.
  • the refrigerant flowing out of ejector 13 passes through pipe 231 to flow into gas-liquid separator 18.
  • gas-liquid separator 18 the refrigerant is separated into a gas-phase refrigerant and a liquid-phase refrigerant.
  • the liquid-phase refrigerant from the inside of gas-liquid separator 18 passes through pipe 232 and flows into first flow channel 141 of split heat exchanger 14.
  • first flow channel 141 the liquid-phase refrigerant exchanges heat with a refrigerant passing through second flow channel 142 of split heat exchanger 14 and is cooled.
  • the liquid-phase refrigerant flowing out of first flow channel 141 passes through pipe 24, branch part 25, unit outlet 2 out , and refrigerant pipe 31 to flow into main throttle mechanism 16.
  • the refrigerant that flows into main throttle mechanism 16 is throttled and expanded by main throttle mechanism 16.
  • the refrigerant flowing out of main throttle mechanism 16 flows into evaporator 17 via refrigerant pipe 33, and is evaporated. At this time, the refrigerant exchanges heat with the surrounding air to generate cold air.
  • the fluid to be subjected to the heat exchange in evaporator 17 does not have to be air.
  • load device 3 may cool water to generate cold water.
  • the gas-phase refrigerant flowing out of evaporator 17 passes through refrigerant pipe 32, unit inlet 2in and pipe 29, and is sucked into main compression mechanism 11 again.
  • the liquid-phase refrigerant which is branched off at branch part 25 and flows into branch pipe 26, flows into auxiliary throttle mechanism 15.
  • the refrigerant that flows into auxiliary throttle mechanism 15 is throttled and expanded by auxiliary throttle mechanism 15.
  • the refrigerant flowing out of auxiliary throttle mechanism 15 flows into second flow channel 142 of split heat exchanger 14 via pipe 27, and is evaporated.
  • the refrigerant flowing into second flow channel 142 exchanges heat with a refrigerant passing through first flow channel 141 to lower the temperature of the refrigerant passing through first flow channel 141.
  • the refrigerant flowing out of second flow channel 142 passes through pipe 28 and is sucked from suction part 132 of ejector 13.
  • the refrigerant sucked from suction part 132 mixes with a refrigerant flowing into nozzle 131 in ejector 13, and then flows out of ejector 13 and flows into gas-liquid separator 18 again.
  • the gas-phase refrigerant from the inside of gas-liquid separator 18 passes through pipe 41 and is sucked into auxiliary compression mechanism 19.
  • the refrigerant sucked into auxiliary compression mechanism 19 is compressed by auxiliary compression mechanism 19 until the refrigerant has a pressure equal to the pressure of a refrigerant at the outlet of main compression mechanism 11, and then discharged to merging pipe 42.
  • the refrigerant discharged from auxiliary compression mechanism 19 to merging pipe 42 joins the refrigerant in pipe 21 discharged from main compression mechanism 11 via merging part 43.
  • auxiliary compression mechanism 19 can reduce the pressure in gas-liquid separator 18, that is, can lower the temperature of a refrigerant in gas-liquid separator 18. This configuration can lower the temperature of a refrigerant supplied to evaporator 17.
  • auxiliary compression mechanism 19 sucks a gas-phase refrigerant from the inside of gas-liquid separator 18 (the refrigerant whose pressure is relatively high), but not a gas-phase refrigerant flowing out of second flow channel 142 (the refrigerant whose pressure is reduced after passing through auxiliary throttle mechanism 15).
  • the gas-phase refrigerant flowing out of second flow channel 142 is sucked by ejector 13. Therefore, the pressure of the refrigerant passing through second flow channel 142 can be reduced by the action of ejector 13 without increasing the power (that is, the input power) of auxiliary compression mechanism 19, and further, the temperature of the refrigerant passing through second flow channel 142 can be lowered.
  • Lowering the temperature of the refrigerant passing through second flow channel 142 can lower the temperature of a refrigerant flowing out of first flow channel 141.
  • This configuration can lower the temperature of a refrigerant supplied to evaporator 17.
  • the refrigeration capacity of refrigeration apparatus 1 thus can be increased, and also the refrigeration efficiency can be improved.
  • control device 50 adjusts the operating frequency of auxiliary compression mechanism 19 based on the detection result from transfer pressure sensor 52. Accordingly, the transfer pressure, that is, the pressure of a refrigerant supplied to main throttle mechanism 16 can be set to a predetermined value. It becomes thus easier to set the pressure of a refrigerant after the refrigerant is throttled by main throttle mechanism 16 to a predetermined value, and as a result, setting the pressure and temperature of a refrigerant flowing into evaporator 17 to predetermined values becomes easier. This configuration allows evaporator 17 to stably generate cold air of desired temperature and quantity.
  • control device 50 adjusts the opening degree of nozzle 131 of ejector 13 based on the detection results from high pressure sensor 53 and from outside air temperature sensor 54 in the present embodiment. That is, control device 50 adjusts the discharge pressure of main compression mechanism 11, namely the pressure of a refrigerant in gas cooler 12, based on the temperature of a fluid for exchanging heat with the refrigerant in gas cooler 12.
  • control device 50 can increase the pressure of a refrigerant in gas cooler 12 by reducing the opening degree of nozzle 131 in such a way that the value detected by high pressure sensor 53 becomes a target value.
  • the flow velocity of the refrigerant in ejector 13 then increases, and the pressure of a refrigerant sucked from suction part 132 decreases.
  • the temperature of the refrigerant supplied from split heat exchanger 14 to main throttle mechanism 16 decreases.
  • control device 50 can reduce the pressure of a refrigerant in gas cooler 12 by increasing the opening degree of nozzle 131 in such a way that the value detected by high pressure sensor 53 becomes a target value.
  • the flow velocity of the refrigerant in ejector 13 then decreases, and the pressure of a refrigerant sucked from suction part 132 increases.
  • the temperature of a refrigerant supplied from split heat exchanger 14 to main throttle mechanism 16 increases.
  • the control as described above can optimize the operating state of main compression mechanism 11, namely the power consumption of main compression mechanism 11, thereby improving energy conservation of refrigeration apparatus 1.
  • control device 50 adjusts the opening degree of auxiliary throttle mechanism 15 based on the detection results from transfer temperature sensor 55 and from second flow channel inlet temperature sensor 56 in the present embodiment.
  • auxiliary throttle mechanism 15 is adjusted in such a way that the value detected by transfer temperature sensor 55 approaches the value detected by second flow channel inlet temperature sensor 56.
  • the control as described above can lower the temperature of a refrigerant supplied to evaporator 17 via main throttle mechanism 16.
  • the refrigeration capacity of refrigeration apparatus 1 thus can be increased, and also the refrigeration efficiency can be improved.
  • the control to adjust the opening degree of auxiliary throttle mechanism 15 based on the detection results from transfer temperature sensor 55 and from second flow channel inlet temperature sensor 56 is particularly effective when the opening degree of nozzle 131 of ejector 13 changes due to changes in the outside temperature and/or the like.
  • the temperature of a refrigerant flowing into second flow channel 142 changes.
  • the temperature of a refrigerant flowing out of first flow channel 141 and supplied to main throttle mechanism 16 may change.
  • adjusting the opening degree of auxiliary throttle mechanism 15 based on the detection results from transfer temperature sensor 55 and from second flow channel inlet temperature sensor 56 can still maintain the temperature of the refrigerant supplied to main throttle mechanism 16 at a desired value.
  • FIG. 3 illustrates a refrigerant circuit of refrigeration apparatus 1 according to Embodiment 3.
  • the description of matters common to Embodiments 1 and 2 may be omitted. Conversely, the description for the present embodiment may apply to Embodiments 1 and 2.
  • main compression mechanism 11 includes low-stage compression mechanism 111 and high-stage compression mechanism 112.
  • Refrigeration apparatus 1 according to the present embodiment also include intercooler 121.
  • Intercooler 121 is disposed between low-stage compression mechanism 111 and high-stage compression mechanism 112 in refrigerant circuit 4 via pipe 44 on the upstream side and pipe 45 on the downstream side.
  • Main compression mechanism 11 is, for example, an internal intermediate-pressure two-stage compression type rotary compressor.
  • Main compression mechanism 11 includes an airtight container and a rotary compression mechanism part.
  • the rotary compression mechanism part includes an electric element that serves as a drive element housed in an upper portion of the internal space of the airtight container, and a first rotary compression element (low-stage compression mechanism 111) and a second rotary compression element (high-stage compression mechanism 112) disposed below the electric element.
  • Main compression mechanism 11 is a two-stage compressor including the first rotary compression element and the second rotary compression element driven by the same rotary shaft (rotary shaft of the electric element).
  • Low-stage compression mechanism 111 and high-stage compression mechanism 112 may be single-stage compression compressors that are independent of each other.
  • Low-stage compression mechanism 111 compresses a refrigerant having a low pressure sucked into main compression mechanism 11 from the low-pressure side of refrigerant circuit 4 via pipe 29, increases the pressure of the refrigerant to an intermediate pressure, and discharges the refrigerant.
  • High-stage compression mechanism 112 sucks in the refrigerant having an intermediate pressure discharged from low-stage compression mechanism 111, compresses the refrigerant until the refrigerant has a high pressure, and discharges the refrigerant to the high-pressure side of refrigerant circuit 4.
  • Main compression mechanism 11 is a frequency-variable compressor.
  • Control device 50 controls the rotation speeds of low-stage compression mechanism 111 and high-stage compression mechanism 112 by changing the operating frequency of the electric element.
  • a low-stage side suction port communicating with low-stage compression mechanism 111
  • a low-stage side discharge port communicating with the inside of the airtight container
  • a high-stage side suction port communicating with high-stage compression mechanism 112
  • a high-stage side discharge port communicating with high-stage compression mechanism 112
  • One end of pipe 29 is connected to the low-stage side suction port of main compression mechanism 11, and the other end of pipe 29 is connected to refrigerant pipe 32 at unit inlet 2in.
  • a refrigerant gas having a low pressure sucked into the low-pressure part of low-stage compression mechanism 111 from the low-stage side suction port is subjected to the first-stage compression by low-stage compression mechanism 111 to have an intermediate pressure, and discharged into the airtight container. As a result, the pressure inside the airtight container becomes an intermediate pressure.
  • pipe 44 is connected to the low-stage side discharge port of main compression mechanism 11 from which the refrigerant gas having the intermediate pressure in the airtight container is discharged, and the other end of pipe 44 is connected to the inlet of intercooler 121.
  • Intercooler 121 cools the intermediate pressure refrigerant gas discharged from low-stage compression mechanism 111.
  • One end of pipe 45 is connected to the outlet of intercooler 121.
  • the other end of pipe 45 is connected to the high-stage side suction port of main compression mechanism 11.
  • the intermediate pressure refrigerant gas sucked into high-stage compression mechanism 112 from the high-stage side suction port of main compression mechanism 11 is subjected to the second-stage compression by high-stage compression mechanism 112 to become a refrigerant gas having high temperature and high pressure.
  • pipe 21 One end of pipe 21 is connected to the high-stage side discharge port provided on the high-pressure chamber side of high-stage compression mechanism 112 in main compression mechanism 11, and the other end of pipe 21 is connected to the inlet of gas cooler 12.
  • An oil separator (not illustrated) may be provided at pipe 21 between the ends of the pipe. The oil separated from the refrigerant by the oil separator is returned to the airtight container of main compression mechanism 11 and the airtight container of auxiliary compression mechanism 19.
  • Gas cooler 12 cools the refrigerant having a high pressure discharged from main compression mechanism 11.
  • a blower for the gas cooler (not illustrated) for air-cooling gas cooler 12 is provided in the vicinity of gas cooler 12.
  • gas cooler 12 is provided in parallel with above described intercooler 121, and the coolers are provided in the same air passage.
  • Gas cooler 12 and intercooler 121 may be water-cooled.
  • a water pump for the gas cooler is provided in place of the blower for the gas cooler, and water is input to the gas cooler and the intercooler in parallel.
  • pipe 22 One end of pipe 22 is connected to the outlet of gas cooler 12, and the other end of pipe 22 is connected to the inlet of nozzle 131 of ejector 13.
  • main compression mechanism 11 includes low-stage compression mechanism 111 and high-stage compression mechanism 112.
  • Intercooler 121 is disposed between low-stage compression mechanism 111 and high-stage compression mechanism 112. This configuration can lower the temperature of a refrigerant after the refrigerant is subjected to the compression as compared with the case of compression of a refrigerant until the refrigerant has the same pressure as in this configuration by using a single-stage compressor.
  • the temperature of the refrigerant discharged from the compressor can be kept relatively low, thereby preventing the denaturing of a lubricating oil in the refrigerant and the damage of piping and the sealing member of the piping.
  • refrigeration apparatus 1 includes ejector 13, gas-liquid separator 18, split heat exchanger 14, auxiliary throttle mechanism 15, and auxiliary compression mechanism 19 in the same manner as refrigeration apparatus 1 according to Embodiment 2.
  • the refrigeration capacity of refrigeration apparatus 1 thus can be increased, and also the refrigeration efficiency can be improved.
  • FIG. 4 is a graph showing the results of electric power simulation in the refrigeration apparatuses according to Embodiment 3 and a reference example.
  • the refrigeration apparatus according to the reference example differs from refrigeration apparatus 1 illustrated in FIG. 3 in the following points.
  • the refrigeration apparatus according to the reference example has the following features.
  • the abscissa represents the evaporation temperature (°C) in evaporator 17, and the ordinate represents the input power (kW) of auxiliary compression mechanism 19.
  • the abscissa represents the evaporation temperature (°C) in evaporator 17, and the ordinate represents the total input power (kW) of auxiliary compression mechanism 19 and main compression mechanism 11.
  • the simulation conditions are as follows.
  • refrigeration system 1 can reduce the input power as compared with the reference example over a wide range of evaporation temperatures in both cases of the input power to auxiliary compression mechanism 19 alone and the total input power to auxiliary compression mechanism 19 and main compression mechanism 11.
  • Refrigeration apparatus 1, which includes ejector 13, gas-liquid separator 18, split heat exchanger 14, auxiliary throttle mechanism 15, and auxiliary compression mechanism 19 disposed in refrigerant circuit 4 as illustrated in FIG. 2 or 3 can efficiently obtain the required refrigeration capacity regardless of the temperature of a refrigerant in evaporator 17.
  • the present disclosure can be widely used for showcases and other refrigeration apparatuses that use refrigeration circuits.

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Devices That Are Associated With Refrigeration Equipment (AREA)
  • Air Conditioning Control Device (AREA)
EP21209825.5A 2020-11-25 2021-11-23 Kühlvorrichtung Withdrawn EP4006443A1 (de)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2020195261A JP2022083749A (ja) 2020-11-25 2020-11-25 冷凍装置

Publications (1)

Publication Number Publication Date
EP4006443A1 true EP4006443A1 (de) 2022-06-01

Family

ID=78770431

Family Applications (1)

Application Number Title Priority Date Filing Date
EP21209825.5A Withdrawn EP4006443A1 (de) 2020-11-25 2021-11-23 Kühlvorrichtung

Country Status (3)

Country Link
EP (1) EP4006443A1 (de)
JP (1) JP2022083749A (de)
CN (1) CN114543382A (de)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0718602B2 (ja) 1989-01-09 1995-03-06 シンヴェント・アクシェセルスカープ 超臨界蒸気圧縮サイクルの運転方法およびその装置
JP3322263B1 (ja) 2000-03-15 2002-09-09 株式会社デンソー エジェクタサイクル、これに用いる気液分離器、並びにこのエジェクタサイクルを用いた給湯器及び熱管理システム
WO2017081157A1 (en) * 2015-11-13 2017-05-18 Danfoss A/S A vapour compression system comprising a secondary evaporator
DE102019111309A1 (de) * 2019-05-02 2020-11-05 Technische Universität Dresden Ejektor-basiertes Kühlungssystem und Kühlungsverfahren

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0718602B2 (ja) 1989-01-09 1995-03-06 シンヴェント・アクシェセルスカープ 超臨界蒸気圧縮サイクルの運転方法およびその装置
JP3322263B1 (ja) 2000-03-15 2002-09-09 株式会社デンソー エジェクタサイクル、これに用いる気液分離器、並びにこのエジェクタサイクルを用いた給湯器及び熱管理システム
WO2017081157A1 (en) * 2015-11-13 2017-05-18 Danfoss A/S A vapour compression system comprising a secondary evaporator
DE102019111309A1 (de) * 2019-05-02 2020-11-05 Technische Universität Dresden Ejektor-basiertes Kühlungssystem und Kühlungsverfahren

Also Published As

Publication number Publication date
JP2022083749A (ja) 2022-06-06
CN114543382A (zh) 2022-05-27

Similar Documents

Publication Publication Date Title
US9523520B2 (en) Air-conditioning apparatus
JP4613916B2 (ja) ヒートポンプ給湯機
US9453668B2 (en) Refrigeration cycle apparatus and refrigerant circulating method
EP2995885B1 (de) Binäre kühlvorrichtung
US20110041523A1 (en) Charge management in refrigerant vapor compression systems
EP2339266B1 (de) Kühlvorrichtung
WO2013111176A1 (ja) 空気調和装置
JP2007139225A (ja) 冷凍装置
JP2011133209A (ja) 冷凍装置
KR101220663B1 (ko) 냉동장치
JP2013155972A (ja) 冷凍装置
CN108603697B (zh) 冷冻装置
KR20110074708A (ko) 냉동장치
EP3862651B1 (de) Kältekreislaufvorrichtung
JP2011137557A (ja) 冷凍装置
EP4006443A1 (de) Kühlvorrichtung
JP6765086B2 (ja) 冷凍装置
JP6206787B2 (ja) 冷凍装置
JP6094859B2 (ja) 冷凍装置
CN106524545B (zh) 冷冻装置
JP2011133208A (ja) 冷凍装置
US11927371B2 (en) Two stage single gas cooler HVAC cycle
JP2014159950A (ja) 冷凍装置
CN108603696B (zh) 冷冻装置
JP2017172923A (ja) 冷凍装置

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION HAS BEEN PUBLISHED

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20221202