EP4166871A1 - Kältekreislaufvorrichtung - Google Patents

Kältekreislaufvorrichtung Download PDF

Info

Publication number
EP4166871A1
EP4166871A1 EP20940550.5A EP20940550A EP4166871A1 EP 4166871 A1 EP4166871 A1 EP 4166871A1 EP 20940550 A EP20940550 A EP 20940550A EP 4166871 A1 EP4166871 A1 EP 4166871A1
Authority
EP
European Patent Office
Prior art keywords
refrigerant
flow paths
refrigerant flow
supercooler
flow path
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.)
Pending
Application number
EP20940550.5A
Other languages
English (en)
French (fr)
Other versions
EP4166871A4 (de
Inventor
Tomotaka Ishikawa
Abastari
Hisato Morita
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.)
Mitsubishi Electric Corp
Original Assignee
Mitsubishi Electric Corp
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 Mitsubishi Electric Corp filed Critical Mitsubishi Electric Corp
Publication of EP4166871A1 publication Critical patent/EP4166871A1/de
Publication of EP4166871A4 publication Critical patent/EP4166871A4/de
Pending legal-status Critical Current

Links

Images

Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25BREFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B40/00Subcoolers, desuperheaters or superheaters
    • F25B40/02Subcoolers
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25BREFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B39/00Evaporators; Condensers
    • F25B39/04Condensers
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25BREFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2400/00General 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
    • F25B2400/13Economisers
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25BREFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2400/00General 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
    • F25B2400/16Receivers
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25BREFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2500/00Problems to be solved
    • F25B2500/01Geometry problems, e.g. for reducing size
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25BREFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B7/00Compression machines, plants or systems, with cascade operation, i.e. with two or more circuits, the heat from the condenser of one circuit being absorbed by the evaporator of the next circuit
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28HEAT EXCHANGE IN GENERAL
    • F28DHEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
    • F28D1/00Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators
    • F28D1/02Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid
    • F28D1/04Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid with tubular conduits
    • F28D1/053Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid with tubular conduits the conduits being straight
    • F28D1/05316Assemblies of conduits connected to common headers, e.g. core type radiators
    • F28D1/05325Assemblies of conduits connected to common headers, e.g. core type radiators with particular pattern of flow, e.g. change of flow direction

Definitions

  • the present disclosure relates to a refrigeration cycle apparatus.
  • a refrigeration cycle apparatus which includes a supercooler for supercooling refrigerant condensed in a condenser (for example, see Japanese Patent Laying-Open No. 2018-091502 (PTL 1)).
  • the supercooler includes a plurality of refrigerant flow paths through which the refrigerant flows.
  • the refrigerant flowing inside the plurality of refrigerant flow paths is supercooled by heat exchange with a heat medium (a cold source) flowing outside the plurality of refrigerant flow paths.
  • the saturation temperature of the gas-liquid two-phase refrigerant is likely to decrease lower than the saturation temperature of the liquid-phase refrigerant. Therefore, when the refrigerant is converted into the gas-liquid two-phase refrigerant as it flows through the supercooler, the temperature difference between the gas-liquid two-phase refrigerant and the heat medium (the cold source) decreases toward the downstream side of the plurality of refrigerant flow paths. In this case, the supercooler cannot supercool the refrigerant, and the refrigerant flows out from the supercooler as the gas-liquid two-phase refrigerant. Thus, as compared with the case where the liquid-phase refrigerant having a degree of supercooling flows through the expansion valve, the flow rate of the refrigerant expanded by the expansion valve is reduced, which deteriorates the capacity of the refrigeration cycle apparatus.
  • a main object of the present disclosure is to provide a refrigeration cycle apparatus which prevents the capacity thereof from being deteriorated by the conversion of refrigerant into gas-liquid two-phase refrigerant in a supercooler.
  • the refrigeration cycle apparatus includes a refrigerant circuit which includes a compressor, a condenser, a supercooler, an expansion valve, and an evaporator, and circulates refrigerant in the order of the compressor, the condenser, the supercooler, the expansion valve, and the evaporator.
  • the supercooler includes a plurality of refrigerant flow paths through which refrigerant flows.
  • the plurality of refrigerant flow paths includes a plurality of first refrigerant flow paths disposed at the most upstream side of the refrigerant circuit among the plurality of refrigerant flow paths, and a plurality of second refrigerant flow paths through which the refrigerant that has flowed through each of the plurality of first refrigerant flow paths flows.
  • the total flow path cross-sectional area of the plurality of first refrigerant flow paths is greater than the total flow path cross-sectional area of the plurality of second refrigerant flow paths.
  • a refrigeration cycle apparatus 100 includes a refrigerant circuit which includes a compressor 1, a condenser 2, a receiver 3, a supercooler 4, an expansion valve 5, and an evaporator 6, and circulates refrigerant.
  • the refrigerant flows through the refrigerant circuit in the order of the compressor 1, the condenser 2, the receiver 3, the supercooler 4, the expansion valve 5, and the evaporator 6.
  • the compressor 1 sucks in the refrigerant evaporated by the evaporator 6, compresses the refrigerant, and discharges the compressed refrigerant.
  • the compressor 1 is, for example, an inverter-controlled compressor capable of changing the capacity thereof by changing the operating frequency.
  • the refrigerant discharged from the compressor 1 is condensed in the condenser 2 by exchanging heat with a heat medium such as air.
  • the refrigerant condensed in the condenser 2 is temporarily stored in the receiver 3 as a saturated liquid. Even when liquid-phase refrigerant having a degree of supercooling flows from the condenser 2 into the receiver 3, the liquid-phase refrigerant cools the vapor-phase refrigerant in the receiver 3, and thereby the degree of supercooling is lost.
  • the receiver 3 has a refrigerant outlet 30 through which the refrigerant flows out.
  • the refrigerant that flows out from the refrigerant outlet 30 of the receiver 3 and flows into the supercooler 4 is a saturated liquid having no degree of supercooling.
  • the refrigerant flowing out from the receiver 3 is supercooled in the supercooler 4 by exchanging heat with a heat medium (hereinafter referred to as a cold source) such as air.
  • the supercooler 4 includes a refrigerant inflow portion 41 through which the refrigerant flows in, a refrigerant outflow portion 42 through which refrigerant flows out, and a plurality of refrigerant flow paths disposed between the refrigerant inflow portion 41 and the refrigerant outflow portion 42 for the refrigerant to flow through.
  • the plurality of refrigerant flow paths are provided in such a manner that the refrigerant flowing through the plurality of refrigerant flow paths exchanges heat with a cold source flowing outside the plurality of refrigerant flow paths.
  • the refrigerant flowing from the supercooler 4 into the expansion valve 5 is liquid-phase refrigerant having a degree of supercooling. The detailed configuration of the supercooler 4 will be described later.
  • the liquid-phase refrigerant which flowing out from the supercooler 4 and has a degree of supercooling is decompressed in the expansion valve 5 and is converted into a gas-liquid two-phase refrigerant.
  • the expansion valve 5 may be replaced by any decompressing device such as a capillary tube capable of decompressing the refrigerant.
  • the refrigerant decompressed by the expansion valve 5 is evaporated in the evaporator 6 by exchanging heat with a heat medium such as air.
  • the supercooler 4 includes, for example, a single heat exchanger.
  • the supercooler 4 is, for example, a parallel flow type (PFC) heat exchanger.
  • the supercooler 4 includes a refrigerant inflow portion 41, a refrigerant outflow portion 42, a plurality of heat transfer tubes 43, a first header 44, and a second header 45.
  • the plurality of heat transfer tubes 43 are disposed in parallel to each other.
  • the plurality of heat transfer tubes 43 includes a plurality of first heat transfer tubes 43A and a plurality of second heat transfer tubes 43B.
  • the flow path cross-sectional area of each of the plurality of first heat transfer tubes 43A is equal to each other, for example.
  • the flow path cross-sectional area of each of the plurality of second heat transfer tubes 43B is equal to each other, for example.
  • the flow path cross-sectional area of each of the plurality of first heat transfer tubes 43A is equal to the flow path cross-sectional area of each of the plurality of second heat transfer tubes 43B, for example.
  • each of the plurality of first heat transfer tubes 43A and one end of each of the plurality of second heat transfer tubes 43B are connected to the first header 44.
  • the other end of each of the plurality of second heat transfer tubes 43B is connected to the second header 45.
  • the length of each of the plurality of first heat transfer tubes 43A in the extending direction is equal to each other, for example.
  • the length of each of the plurality of second heat transfer tubes 43B in the extending direction is equal to each other, for example.
  • the length of each of the plurality of first heat transfer tubes 43A in the extending direction is equal to the length of each of the plurality of second heat transfer tubes 43B in the extending direction, for example.
  • the plurality of heat transfer tubes 43 are disposed in such a manner that the plurality of heat transfer tubes 43 extend in the horizontal direction and are separated from each other with an interval in the vertical direction, for example.
  • the plurality of first heat transfer tubes 43A are disposed in such a manner that the plurality of first heat transfer tubes 43A are separated from each other with an interval in the vertical direction.
  • the plurality of second heat transfer tubes 43B are disposed in such a manner that the plurality of second heat transfer tubes 43B are separated from each other with an interval in the vertical direction.
  • the plurality of first heat transfer tubes 43A are disposed above the plurality of second heat transfer tubes 43B, for example.
  • a first heat transfer tube 43A which is disposed at the lowest position among the plurality of first heat transfer tubes 43A, is disposed above a second heat transfer tube 43B, which is disposed at the highest position among the plurality of second heat transfer tubes 43B.
  • Each of the plurality of refrigerant flow paths is formed inside a corresponding one of the plurality of heat transfer tubes 43.
  • the air serving as a cold source flows outside the plurality of heat transfer tubes 43.
  • the plurality of refrigerant flow paths are provided in such a manner that the refrigerant flowing inside the plurality of heat transfer tubes 43 exchanges heat with the cold source flowing outside the plurality of heat transfer tubes 43.
  • the plurality of refrigerant flow paths includes a plurality of first refrigerant flow paths P1, each of which is formed inside a corresponding one of the plurality of first heat transfer tubes 43A, and a plurality of second refrigerant flow paths P2, each of which is formed inside a corresponding one of the plurality of second heat transfer tubes 43B.
  • the plurality of refrigerant flow paths includes a plurality of first refrigerant flow paths P1 disposed at the most upstream side of the refrigerant circuit among the plurality of refrigerant flow paths, and a plurality of second refrigerant flow paths P2 through which the refrigerant that has flowed through each of the plurality of first refrigerant flow paths P1 flows.
  • the flow path cross-sectional area of each of the plurality of first refrigerant flow paths P1 is equal to the flow path cross-sectional area of each of the plurality of second refrigerant flow paths P2.
  • An upstream end of each of the plurality of first refrigerant flow paths P1 is connected to the first header 44.
  • a downstream end of each of the plurality of first refrigerant flow paths P1 is connected to the second header 45.
  • the plurality of first refrigerant flow paths P1 are connected in parallel to each other between the first header 44 and the second header 45.
  • An upstream end of each of the plurality of second refrigerant flow paths P2 is connected to the second header 45.
  • a downstream end of each of the plurality of second refrigerant flow paths P2 is connected to the first header 44.
  • the plurality of second refrigerant flow paths P2 are connected in parallel to each other between the first header 44 and the second header 45.
  • Each of the plurality of second refrigerant flow paths P2 is connected in series with each of the plurality of first refrigerant flow paths P 1.
  • the total flow path cross-sectional area of the plurality of first heat transfer tubes 43A is greater than the total flow path cross-sectional area of the plurality of second heat transfer tubes 43B.
  • the number of the first heat transfer tubes 43A is greater than the number of the second heat transfer tubes 43B.
  • the total flow path cross-sectional area of the plurality of first refrigerant flow paths P1 is greater than the total flow path cross-sectional area of the plurality of second refrigerant flow paths P2.
  • the number of the plurality of first refrigerant flow paths P1 is greater than the number of the plurality of second refrigerant flow paths P2.
  • the total flow path cross-sectional area of the plurality of first refrigerant flow paths P1 is 1.4 times or more and 2 times or less as great as the total flow path cross-sectional area of the plurality of second refrigerant flow paths P2.
  • the number of the plurality of first refrigerant flow paths P1 is 1.4 times or more and 2 times or less as great as the number of the plurality of second refrigerant flow paths P2.
  • the first header 44 includes a first space 44A that is contiguous to the upstream end of each of the plurality of first refrigerant flow paths P1, a second space 44B that is contiguous to the downstream end of each of the plurality of second refrigerant flow paths P2, and a partition 46 that partitions the first space 44A and the second space 44B.
  • the first space 44A is contiguous to the refrigerant inflow portion 41.
  • the second space 44B is contiguous to the refrigerant outflow portion 42.
  • the first space 44A and the second space 44B are formed inside the first header 44.
  • the partition 46 is fixed inside the first header 44.
  • the second header 45 has an internal space that is contiguous to both the downstream end of each of the plurality of first refrigerant flow paths P1 and the upstream end of each of the plurality of second refrigerant flow paths P2.
  • the refrigerant flowing from the refrigerant inflow portion 41 into the first space 44A of the first header 44 is distributed to each of the plurality of first refrigerant flow paths P1.
  • the refrigerant flowing through each of the plurality of first refrigerant flow paths P1 merges in the inner space of the second header 45, and then is distributed to each of the plurality of second refrigerant flow paths P2.
  • the refrigerant flowing through each of the plurality of second refrigerant flow paths P2 merges in the second space 44B of the first header 44, and then flows out from the refrigerant outflow portion 42.
  • the supercooler 4 further includes a plurality of fins 47.
  • Each of the fins 47 is a corrugate fin.
  • Each of the fins 47 is connected to an outer peripheral surface of each of the heat transfer tubes 43.
  • Each of the fins 47 faces the flow path of the cold source. The direction in which the cold source flows intersects the extending direction of each of the plurality of heat transfer tubes 43.
  • Each of the fins 47 is disposed, for example, between two of the first heat transfer tubes 43A adjacent to each other in the vertical direction, or between two of the second heat transfer tubes 43B adjacent to each other in the vertical direction, or between a first heat transfer tube 43A disposed at the lowest position among the plurality of first heat transfer tubes 43A and a second heat transfer tube 43B disposed at the highest position among the plurality of second heat transfer tubes 43B.
  • the supercooler 4 includes a first heat exchange unit 4A which exchanges heat between the refrigerant flowing inside the plurality of first heat transfer tubes 43A and the cold source such as air flowing outside the plurality of first heat transfer tubes 43A, and a second heat exchange unit 4B which exchanges heat between the refrigerant flowing inside the plurality of second heat transfer tubes 43B and the cold source such as air flowing outside the plurality of second heat transfer tubes 43B.
  • the first heat exchange unit 4A is disposed upstream of the second heat exchange unit 4B and is connected in series with the second heat exchange unit 4B.
  • Each of the first heat exchange unit 4A and the second heat exchange unit 4B is formed as a part of a single heat exchanger.
  • a refrigeration cycle apparatus according to comparative example 1 or 2 is different from the refrigeration cycle apparatus 100 only in that the refrigeration cycle apparatus according to comparative example 1 or 2 is provided with a supercooler in which the total flow path cross-sectional area of the refrigerant flow paths located at the upstream side (hereinafter referred to as the upstream refrigerant flow paths) is equal to the total flow path cross-sectional area of the refrigerant flow paths located at the downstream side (hereinafter referred to as the downstream refrigerant flow paths).
  • the total flow path cross-sectional area of the upstream refrigerant flow paths is equal to the total flow path cross-sectional area of the downstream refrigerant flow paths.
  • the total flow path cross-sectional area of the downstream refrigerant flow paths of the supercooler of comparative example 1 is equal to the total flow path cross-sectional area of the plurality of second refrigerant flow paths P2 of the supercooler 4.
  • the total flow path cross-sectional area of the upstream refrigerant flow paths of the supercooler of comparative example 1 is smaller than the total flow path cross-sectional area of the plurality of first refrigerant flow paths P1 of the supercooler 4.
  • the pressure loss of the refrigerant in the plurality of first refrigerant flow paths P1 of the supercooler 4 is smaller than the pressure loss of the refrigerant in the upstream refrigerant flow path of the supercooler of comparative example 1.
  • the total flow path cross-sectional area of the upstream refrigerant flow paths is equal to the total flow path cross-sectional area of the downstream refrigerant flow paths.
  • the total flow path cross-sectional area of the upstream refrigerant flow paths of the supercooler of comparative example 2 is equal to the total flow path cross-sectional area of the plurality of first refrigerant flow paths P1 of the supercooler 4.
  • the total flow path cross-sectional area of the downstream refrigerant flow paths of the supercooler of comparative example 2 is greater than the total flow path cross-sectional area of the plurality of second refrigerant flow paths P2 of the supercooler 4.
  • the flow velocity of the refrigerant flowing through the plurality of second refrigerant flow paths P2 of the supercooler 4 is higher than the flow velocity of the refrigerant flowing through the downstream refrigerant flow paths of the supercooler of comparative example 2.
  • the supercooler 4 is compared with the supercooler of comparative example 1. Assume that the refrigerant flowing through the supercooler 4 has the same type, the same flow rate and the same saturation temperature as the refrigerant flowing through the supercooler of comparative example 1.
  • the refrigerant which is a saturated liquid having no degree of supercooling flows from the refrigerant inflow portion into the plurality of first refrigerant flow paths or the upstream refrigerant flow paths.
  • the refrigerant flows through the plurality of first refrigerant flow paths or the upstream refrigerant flow paths to exchange heat with the heat medium (the cold source).
  • the heat medium the cold source
  • a pressure loss occurs in the refrigerant. Since the saturation temperature of the refrigerant corresponds to the pressure of the refrigerant, the greater the pressure loss of the refrigerant is, the lower the saturation temperature of the refrigerant will be.
  • Fig. 3 is a graph illustrating a change in the temperature of the refrigerant flowing from the refrigerant inflow portion 41 into the refrigerant outflow portion 42 and a change in the saturation temperature of the refrigerant in the supercooler 4.
  • Fig. 10 is a graph illustrating a change in the temperature of the refrigerant flowing from the refrigerant inflow portion into the refrigerant outflow portion and a change in the saturation temperature of the refrigerant in the supercooler of comparative example 1.
  • a solid line indicates a change in the temperature of the refrigerant
  • a dotted line indicates a change in the saturation temperature of the refrigerant.
  • the refrigerant is likely to be converted into gas-liquid two-phase refrigerant during the flowing. In other words, it is likely that the gas-liquid two-phase refrigerant flows in the downstream refrigerant flow path of the supercooler of comparative example 1.
  • the pressure loss of the gas-liquid two-phase refrigerant flowing through the downstream refrigerant flow path is greater than the pressure loss of the refrigerant flowing through the upstream refrigerant flow path before it is converted to the gas-liquid two-phase refrigerant.
  • the saturation temperature of the gas-liquid two-phase refrigerant flowing through the downstream refrigerant flow path is likely to become lower than that of the refrigerant flowing through the upstream refrigerant flow path before it is converted to the gas-liquid two-phase refrigerant.
  • the temperature difference between the refrigerant flowing through the downstream refrigerant flow path and the heat medium (the cold source) is smaller than the temperature difference between the refrigerant flowing through the upstream refrigerant flow path and the heat medium, and becomes smaller as the refrigerant flows toward the refrigerant outflow portion. Therefore, in the supercooler of comparative example 1, the gas-liquid two-phase refrigerant flows out from the refrigerant outflow portion without being supercooled.
  • the refrigerant in the supercooler of comparative example 1, the refrigerant is likely to be converted into gas-liquid two-phase refrigerant, and the gas-liquid two-phase refrigerant flows out without being supercooled.
  • the refrigeration cycle apparatus according to comparative example 1 since the gas-liquid two-phase refrigerant flowing out from the supercooler flows into the expansion valve, the flow rate of the refrigerant expanded in the expansion valve is reduced as compared with the case where the liquid-phase refrigerant having a degree of supercooling flows into the expansion valve, and thereby, the capacity of the refrigeration cycle apparatus is deteriorated.
  • the total flow path cross-sectional area of the plurality of first refrigerant flow paths P1 of the supercooler 4 is greater than the total flow path cross-sectional area of the upstream refrigerant flow paths of the supercooler of comparative example 1. Therefore, as illustrated in Fig. 3 , the pressure loss of the refrigerant as it flows through each first refrigerant flow path P1 of the supercooler 4 is smaller than the pressure loss of the refrigerant as it flows through the upstream refrigerant flow path of the supercooler of comparative example 1. As illustrated in Figs.
  • the amount of decrease in the saturation temperature of the refrigerant as it flows through each first refrigerant flow path P1 is smaller than the amount of decrease in the saturation temperature of the refrigerant as it flows through the upstream refrigerant flow path.
  • the refrigerant flows through the upstream refrigerant flow path of comparative example 1
  • the refrigerant flows through each first refrigerant flow path P1
  • the refrigerant is less likely to be converted into gas-liquid two-phase refrigerant, and thereby, the pressure loss of the refrigerant is smaller and the amount of decrease in the saturated temperature of the refrigerant is smaller. Therefore, as the refrigerant flows through each first refrigerant flow path P1, the refrigerant is sufficiently supercooled as compared with the case where the refrigerant flows through the upstream refrigerant flow path of comparative example 1.
  • the liquid-phase refrigerant having a degree of supercooling flows from each first refrigerant flow path P1 into each second refrigerant flow path P2.
  • the temperature of the refrigerant flowing into each of the second refrigerant flow paths P2 may be lower than the saturation temperature of the refrigerant flowing out from the refrigerant outflow portion 42.
  • the total flow path cross-sectional area of the plurality of second refrigerant flow paths P2 of the supercooler 4 is equal to the total flow path cross-sectional area of the downstream refrigerant flow paths of the supercooler of comparative example 1.
  • the saturation temperature of the liquid-phase refrigerant is less likely to decrease lower than the saturation temperature of the gas-liquid two-phase refrigerant as the gas-liquid two-phase refrigerant flows through the downstream refrigerant flow path of comparative example 1.
  • the liquid-phase refrigerant flowing into the plurality of second refrigerant flow paths P2 is not converted into the gas-liquid two-phase refrigerant, but flows out from the refrigerant outflow portion 42 while maintaining the degree of supercooling.
  • the refrigerant in the supercooler 4, the refrigerant is prevented from being converted into the gas-liquid two-phase refrigerant as it flows through each of the plurality of first refrigerant flow paths P1 and each of the plurality of second refrigerant flow paths P2, and thereby, the refrigerant having a degree of supercooling flows out from the refrigerant outflow portion 42.
  • the refrigeration cycle apparatus 100 including the supercooler 4 since the refrigerant flowing out from the supercooler 4 into the expansion valve 5 is liquid-phase refrigerant, the capacity of the refrigeration cycle apparatus 100 is improved as compared with the refrigeration cycle apparatus according to comparative example 1.
  • the pressure loss of the refrigerant as it flows through each of the second refrigerant flow paths P2 is greater than the pressure loss of the refrigerant as it flows through each of the first refrigerant flow paths P1. Therefore, in the supercooler 4, the saturation temperature of the refrigerant as it flows through each of the second refrigerant flow paths P2 is smaller than the saturation temperature of the refrigerant as it flows through each of the first refrigerant flow paths P1.
  • the degree of supercooling of the refrigerant flowing into each of the second refrigerant flow paths P2 can be made sufficiently large, it is possible to ensure the degree of supercooling of the refrigerant flowing out from the refrigerant outflow portion 42.
  • the refrigerant flowing out from the supercooler 4 into the expansion valve 5 is liquid-phase refrigerant, the capacity of the refrigeration cycle apparatus is prevented from being deteriorated by the gas-liquid two-phase refrigerant flowing into the expansion valve.
  • the supercooler 4 is compared with the supercooler of comparative example 2. Assume that the refrigerant flowing through the supercooler 4 has the same type, the same flow rate and the same saturation temperature as the refrigerant flowing through the supercooler of comparative example 2. Similar to the refrigerant flowing through the plurality of first refrigerant flow paths P 1 of the supercooler 4, as the refrigerant flows through the upstream refrigerant flow path of the supercooler of comparative example 2, the refrigerant is sufficiently supercooled, and thereby, the liquid-phase refrigerant having a degree of supercooling flows into the downstream refrigerant flow path.
  • the total flow path cross-sectional area of the downstream refrigerant flow paths of comparative example 2 is greater than the total flow path cross-sectional area of the downstream refrigerant flow paths of comparative example 1
  • the flow velocity of the liquid-phase refrigerant flowing through the downstream refrigerant flow paths of comparative example 2 is slower than the flow velocity of the gas-liquid two-phase refrigerant flowing through the downstream refrigerant flow paths of comparative example 1. Since the heat transfer coefficient of the downstream refrigerant flow paths of comparative example 2 is low, it is difficult to encure the degree of supercooling of the refrigerant flowing out from the refrigerant outflow portion.
  • the number of the second refrigerant flow paths P2 is smaller than the number of the first refrigerant flow paths P1, and is smaller than the number of the downstream refrigerant flow paths of comparative example 2. Therefore, the flow velocity of the refrigerant flowing through the plurality of second refrigerant flow paths P2 is higher than the flow velocity of the refrigerant flowing through the plurality of first refrigerant flow paths P1, and is higher than the flow velocity of the refrigerant flowing through the downstream refrigerant flow paths of comparative example 2.
  • the heat transfer coefficient in each of the second refrigerant flow paths P2 is sufficiently high, which makes it possible to ensure the degree of supercooling of the refrigerant flowing out from the refrigerant outflow portion 42.
  • the capacity of the refrigeration cycle apparatus is prevented from being deteriorated by the gas-liquid two-phase refrigerant flowing into the expansion valve.
  • Figs. 4 to 6 are block diagrams, each of which illustrates a modification of the refrigeration cycle apparatus 100.
  • the supercooler 4 may include two or more heat exchangers.
  • Each of the first heat exchange unit 4A and the second heat exchange unit 4B may be a single heat exchanger. Since a refrigeration cycle apparatus 101 illustrated in Fig. 4 has substantially the same configuration as the refrigeration cycle apparatus 100, it can obtain the same effects as the refrigeration cycle apparatus 100.
  • each of the first heat exchange unit 4A and the second heat exchange unit 4B is not limited to a PFC type heat exchanger, and may be any heat exchanger.
  • Each of the first heat exchange unit 4A and the second heat exchange unit 4B may be, for example, a heat exchanger including a plurality of heat transfer tubes 43 and a plurality of plate fins.
  • each of the first heat exchange unit 4A and the second heat exchange unit 4B may be a plate heat exchanger including a plurality of heat transfer plates stacked on each other to replace the plurality of heat transfer tubes 43.
  • the plurality of first refrigerant flow paths P1 are formed between two heat transfer plates adjacent to each other in the stacking direction of the plurality of heat transfer plates, and are alternately arranged with the flow paths of the plurality of cold sources in the stacking direction.
  • the plurality of second refrigerant flow paths P2 are formed between two heat transfer plates adjacent to each other in the stacking direction of the plurality of heat transfer plates, and are alternately arranged with the flow paths of the plurality of cold sources in the stacking direction.
  • a refrigeration cycle apparatus 102 may further include an injection flow path 11.
  • the injection flow path 11 includes an injection expansion valve 7.
  • One end of the injection flow path 11 is connected to a refrigerant path located between the supercooler 4 and the expansion valve 5 in the refrigerant circuit 10.
  • the other end of the injection flow path 11 is connected to an intermediate pressure port of the compressor 1.
  • the supercooler 4 may be provided as an internal heat exchanger which exchanges heat between the refrigerant flowing between the receiver 3 and the expansion valve 5 and the refrigerant flowing between the injection expansion valve 7 and the compressor 1 in the injection flow path 11.
  • each of the plurality of first refrigerant flow paths P 1 and the plurality of second refrigerant flow paths P2 is disposed downstream of the receiver 3 and upstream of the one end of the injection flow path 11 in the refrigerant circuit 10.
  • the refrigerant flowing between the injection expansion valve 7 and the compressor 1 in the injection flow path 11 serves as a cold source.
  • the supercooler 4 illustrated in Fig. 5 includes, for example, a first heat exchange unit 4A and a second heat exchange unit 4B.
  • Each of the first heat exchange unit 4A and the second heat exchange unit 4B is, for example, a plate heat exchanger as described above.
  • the refrigeration cycle apparatus 102 illustrated in Fig. 5 has substantially the same configuration as the refrigeration cycle apparatus 100, it can obtain the same effects as the refrigeration cycle apparatus 100.
  • a refrigeration cycle apparatus 103 may further include a second refrigerant circuit 12.
  • the second refrigerant circuit 12 circulates a refrigerant different from that circulated in the refrigerant circuit 10.
  • the second refrigerant circuit 12 includes a second compressor 13, a second condenser 14, a second expansion valve 15, and a supercooler 4 that functions as an evaporator in the second refrigerant circuit 12.
  • the refrigerant decompressed by the second expansion valve 15 serves as a cold source of the supercooler 4.
  • the supercooler 4 illustrated in Fig. 6 includes, for example, a first heat exchange unit 4A and a second heat exchange unit 4B.
  • Each of the first heat exchange unit 4A and the second heat exchange unit 4B is, for example, a plate heat exchanger as described above.
  • the refrigeration cycle apparatus 103 illustrated in Fig. 6 has substantially the same configuration as the refrigeration cycle apparatus 100, it can obtain the same effects as the refrigeration cycle apparatus 100.
  • Fig. 7 is a diagram illustrating a modification of the supercooler 4.
  • the supercooler 4 illustrated in Fig. 7 further includes a plurality of connection members 50, each of which connects a downstream end of each of two first refrigerant flow paths P1 to an upstream end of one second refrigerant flow path P2.
  • each of the plurality of first refrigerant flow paths P1 and each of the plurality of second refrigerant flow paths P2 are connected in series via the plurality of connection members 50 instead of the second header 45 illustrated in Fig. 2 .
  • connection members 50 is provided as, for example, a branched pipe.
  • Each of the connection members 50 may be provided in any means as long as it can connect a downstream end of each of at least two first refrigerant flow paths P1 to an upstream end of at least one second refrigerant flow path P2.
  • the supercooler 4 may include at least one connection member 50.
  • a refrigeration cycle apparatus 104 has substantially the same configuration as the refrigeration cycle apparatus 100 according to the first embodiment, but is different from the refrigeration cycle apparatus 100 in that the refrigerant circuit 10 of the refrigeration cycle apparatus 104 further includes a booster unit configured to boost the refrigerant flowing from the refrigerant outlet 30 of the receiver 3 into the refrigerant inflow portion 41 of the supercooler 4.
  • the refrigerant circuit 10 of the refrigeration cycle apparatus 104 illustrated in Fig. 8 includes a descending pipe line 10A as the booster unit.
  • One end of the descending pipe line 10A is disposed at the upstream side of the refrigerant circuit 10, and the other end thereof is disposed at the downstream side of the refrigerant circuit 10.
  • the one end of the descending pipe line 10A is disposed above the other end of the descending pipe line 10A.
  • the refrigeration cycle apparatus 104 differs from the refrigeration cycle apparatus 100 in that the refrigerant outlet 30 of the receiver 3 is disposed above the refrigerant inflow portion 41 of the supercooler 4.
  • the refrigeration cycle apparatus 104 Since the refrigeration cycle apparatus 104 has substantially the same configuration as the refrigeration cycle apparatus 100, it can obtain the same effects as the refrigeration cycle apparatus 100. Further, in the refrigeration cycle apparatus 104, the refrigerant flowing out from the refrigerant outlet 30 of the receiver 3 is boosted by the descending pipe line 10A, and then flows into the refrigerant inflow portion 41 of the supercooler 4. Therefore, the saturation temperature of the refrigerant flowing through the plurality of first refrigerant flow paths P1 in the refrigeration cycle apparatus 104 is higher than the saturation temperature of the refrigerant flowing through the plurality of first refrigerant flow paths P1 in the refrigeration cycle apparatus 100.
  • the degree of supercooling of the refrigerant flowing out from the refrigerant outflow portion 42 in the refrigeration cycle apparatus 104 is further higher than the degree of supercooling of the refrigerant flowing out from the refrigerant outflow portion 42 in the refrigeration cycle apparatus 100. Therefore, it is more reliably to prevent the capacity of the refrigeration cycle apparatus 104 from being deteriorated by the conversion of refrigerant into gas-liquid two-phase refrigerant in the supercooler 4.
  • the booster unit may have any configuration as long as it can boost the refrigerant flowing from the refrigerant outlet 30 of the receiver 3 into the refrigerant inflow portion 41 of the supercooler 4.
  • the refrigerant circuit 10 of a refrigeration cycle apparatus 105 illustrated in Fig. 9 includes a booster pump 8 as the booster unit. Similar to the descending pipe line 10A, the booster pump 8 boosts the refrigerant flowing from the refrigerant outlet 30 of the receiver 3 into the refrigerant inflow portion 41 of the supercooler 4.
  • the booster pump 8 may have any configuration as long as it can boost the refrigerant that flows out from the refrigerant outlet 30 of the receiver 3 as a saturated liquid having no degree of supercooling, and it may be, for example, a reciprocating pump that includes a cylinder and a piston which reciprocates inside the cylinder.
  • the refrigeration cycle apparatus 105 since the refrigeration cycle apparatus 105 has substantially the same configuration as the refrigeration cycle apparatus 104, it can obtain the same effects as the refrigeration cycle apparatus 104.
  • the refrigerant circuit 10 of the refrigeration cycle apparatus 105 may further include a descending pipe line 10A as the booster unit.
  • the booster pump 8 and the descending pipe line 10A are connected in series in the refrigerant circuit 10.
  • the booster pump 8 is disposed, for example, on the downstream side of the descending pipe line 10A.
  • the booster pump 8 may be disposed, for example, on the downstream side of the descending pipe line 10A.
  • the supercooler 4 of the refrigeration cycle apparatus 104 or 105 according to the second embodiment may have the same configuration as the supercooler 4 illustrated in Figs. 4 to 7 .
  • the refrigerant circuit 10 in each of the refrigeration cycle apparatuses 100 to 105 according to the first or second embodiment may not include the receiver 3.
  • the liquid-phase refrigerant having a degree of supercooling can flow from the condenser 2 into the supercooler 4, it is more reliably to prevent the capacity from being deteriorated by the conversion of refrigerant into gas-liquid two-phase refrigerant in the supercooler 4 than the refrigeration cycle apparatuses 100 to 105 described above.
  • the supercooler 4 in each of the refrigeration cycle apparatuses 100 to 105 according to the first or second embodiment may include at least one second refrigerant flow path P2.

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)
EP20940550.5A 2020-06-15 2020-06-15 Kältekreislaufvorrichtung Pending EP4166871A4 (de)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/JP2020/023429 WO2021255790A1 (ja) 2020-06-15 2020-06-15 冷凍サイクル装置

Publications (2)

Publication Number Publication Date
EP4166871A1 true EP4166871A1 (de) 2023-04-19
EP4166871A4 EP4166871A4 (de) 2023-08-09

Family

ID=79268646

Family Applications (1)

Application Number Title Priority Date Filing Date
EP20940550.5A Pending EP4166871A4 (de) 2020-06-15 2020-06-15 Kältekreislaufvorrichtung

Country Status (4)

Country Link
EP (1) EP4166871A4 (de)
JP (1) JP7341340B2 (de)
CN (1) CN115698607A (de)
WO (1) WO2021255790A1 (de)

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20010037650A1 (en) * 2000-01-25 2001-11-08 Optimum Air Corporation Dehumidification system having a coil split subcooler for removing moisture from an air flow and methods thereof
JP2003106708A (ja) * 2001-09-28 2003-04-09 Showa Denko Kk 冷凍システム、冷凍サイクル用凝縮装置及びレシーバタンク付き熱交換器
JP2005106329A (ja) * 2003-09-29 2005-04-21 Sanden Corp サブクールタイプコンデンサ
GB0326443D0 (en) * 2003-11-13 2003-12-17 Calsonic Kansei Uk Ltd Condenser
JP2006343039A (ja) * 2005-06-09 2006-12-21 Kobe Steel Ltd ヒートポンプ
JP4803199B2 (ja) * 2008-03-27 2011-10-26 株式会社デンソー 冷凍サイクル装置
WO2012098912A1 (ja) * 2011-01-21 2012-07-26 ダイキン工業株式会社 熱交換器および空気調和機
JP5579243B2 (ja) * 2012-10-26 2014-08-27 三菱電機株式会社 冷凍サイクル装置
JP2020016339A (ja) * 2016-10-18 2020-01-30 株式会社エコラ・テック 放熱器、凝縮器ユニット、冷凍サイクル
JP6825336B2 (ja) 2016-11-30 2021-02-03 ダイキン工業株式会社 冷凍装置
JP2019163867A (ja) * 2018-03-19 2019-09-26 株式会社Nttファシリティーズ 蒸気圧縮式冷凍機

Also Published As

Publication number Publication date
JPWO2021255790A1 (de) 2021-12-23
JP7341340B2 (ja) 2023-09-08
EP4166871A4 (de) 2023-08-09
CN115698607A (zh) 2023-02-03
WO2021255790A1 (ja) 2021-12-23

Similar Documents

Publication Publication Date Title
US8235101B2 (en) Parallel flow heat exchanger for heat pump applications
US6536231B2 (en) Tube and shell heat exchanger for multiple circuit refrigerant system
US10371422B2 (en) Condenser with tube support structure
US20110056667A1 (en) Integrated multi-circuit microchannel heat exchanger
EP1870648A1 (de) Ausstoss-kühlzykluseinheit
JP2003121092A (ja) 熱交換器
US20140102131A1 (en) Outdoor unit of refrigeration system
JP2018162900A (ja) 熱交換器、および、それを備えた空気調和機
US20170074591A1 (en) Micro channel type heat exchanger
JP6351875B1 (ja) 熱交換器及び冷凍サイクル装置
KR101173157B1 (ko) 수냉식 응축기 및 과냉각용 수냉식 열교환기를 구비하는 차량용 공조 시스템
US20230128871A1 (en) Heat exchanger, outdoor unit, and refrigeration cycle device
EP4166871A1 (de) Kältekreislaufvorrichtung
RU2693946C2 (ru) Стойкий к образованию инея микроканальный теплообменник
CN108692489B (zh) 热交换器用连接装置
EP4163579A1 (de) Wärmetauscher und klimaanlagenvorrichtung damit
US11867466B2 (en) Compact heat exchanger assembly for a refrigeration system
US11898781B2 (en) Gas header, heat exchanger, and refrigeration cycle apparatus
KR20170069522A (ko) 냉장고
JP2003207230A (ja) 冷凍サイクルおよび冷凍サイクルの受液器容積決定方法
JP7370501B1 (ja) 熱交換器及び空気調和装置
US11506431B2 (en) Refrigeration cycle apparatus
US20240011648A1 (en) Microchannel heat exchanger for heat pump
JP2018146153A (ja) 凝縮器
JP6888616B2 (ja) 熱交換装置、冷凍システム及び熱交換方法

Legal Events

Date Code Title Description
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE INTERNATIONAL PUBLICATION HAS BEEN MADE

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: REQUEST FOR EXAMINATION WAS MADE

17P Request for examination filed

Effective date: 20221017

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

A4 Supplementary search report drawn up and despatched

Effective date: 20230706

RIC1 Information provided on ipc code assigned before grant

Ipc: F25B 40/02 20060101AFI20230630BHEP

DAV Request for validation of the european patent (deleted)
DAX Request for extension of the european patent (deleted)