EP3239640A1 - Appareil à cycle de réfrigération - Google Patents

Appareil à cycle de réfrigération Download PDF

Info

Publication number
EP3239640A1
EP3239640A1 EP14909044.1A EP14909044A EP3239640A1 EP 3239640 A1 EP3239640 A1 EP 3239640A1 EP 14909044 A EP14909044 A EP 14909044A EP 3239640 A1 EP3239640 A1 EP 3239640A1
Authority
EP
European Patent Office
Prior art keywords
refrigerant
flat tubes
refrigeration cycle
cycle apparatus
heat exchanger
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Withdrawn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
EP14909044.1A
Other languages
German (de)
English (en)
Other versions
EP3239640A4 (fr
Inventor
Shin Nakamura
Hideaki Maeyama
Akira Ishibashi
Shinya Higashiiue
Daisuke Ito
Shigeyoshi MATSUI
Takumi NISHIYAMA
Yuki UGAJIN
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 EP3239640A1 publication Critical patent/EP3239640A1/fr
Publication of EP3239640A4 publication Critical patent/EP3239640A4/fr
Withdrawn legal-status Critical Current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
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F1/00—Tubular elements; Assemblies of tubular elements
    • F28F1/02—Tubular elements of cross-section which is non-circular
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
    • F28D1/00—Heat-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
    • F28D1/02—Heat-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
    • F28D1/04—Heat-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
    • F28D1/053—Heat-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
    • F28D1/0535—Heat-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 the conduits having a non-circular cross-section
    • F28D1/05366—Assemblies of conduits connected to common headers, e.g. core type radiators
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F1/00—Tubular elements; Assemblies of tubular elements
    • F28F1/02—Tubular elements of cross-section which is non-circular
    • F28F1/022—Tubular elements of cross-section which is non-circular with multiple channels
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
    • F28D21/00—Heat-exchange apparatus not covered by any of the groups F28D1/00 - F28D20/00
    • F28D2021/0019—Other heat exchangers for particular applications; Heat exchange systems not otherwise provided for
    • F28D2021/0068—Other heat exchangers for particular applications; Heat exchange systems not otherwise provided for for refrigerant cycles

Definitions

  • the present invention relates to a refrigeration cycle apparatus including heat exchangers.
  • Patent Literature 1 Japanese Unexamined Patent Application Publication No. 2014-098166
  • Refrigerant containing HFO refrigerant as in HFO-1123 of Patent Literature 1 conventionally has a low global warming potential (hereinafter referred to as "GWP"), and therefore, has a short atmospheric lifetime. That is, due to poor stability, the refrigerant is easily decomposed even in the case where the refrigerant is in a refrigerant circuit including heat exchangers. Consequently, a reduction in performance of the refrigeration cycle apparatus and a reduction in reliability of the refrigeration cycle apparatus are caused.
  • GWP global warming potential
  • the present invention has been made in view of the above-described problem, and is intended to provide a refrigeration cycle apparatus having improved heat transfer performance of a heat exchanger in the case of using HFO-1123 or a refrigerant mixture containing HFO-1123 as refrigerant circulating in a refrigerant circuit.
  • a refrigeration cycle apparatus of an embodiment of the present invention includes a refrigerant circuit including a compressor, a first heat exchanger, an expansion unit, and a second heat exchanger connected in sequence to each other via pipes to circulate refrigerant through the refrigerant circuit.
  • the refrigerant is one of HFO-1123 and a refrigerant mixture containing HFO-1123.
  • At least one of the first heat exchanger and the second heat exchanger includes a plurality of fins and a plurality of flat tubes.
  • the plurality of flat tubes each include a plurality of passages through which the refrigerant flows. Where the plurality of flat tubes each have a thickness DA, a relationship expressed by 0.9 mm ⁇ DA ⁇ 3.0 mm is satisfied.
  • the relationship of 0.9 mm ⁇ DA ⁇ 3.0 mm is satisfied, where the thickness of the flat tube is represented by DA.
  • heat transfer performance of the heat exchanger can be improved in the case of using HFO-1123 or a refrigerant mixture containing HFO-1123 as the refrigerant circulating in the refrigerant circuit.
  • an air-conditioning apparatus is described as an example of a refrigeration cycle apparatus of the present invention, but the present invention is not limited to the air-conditioning apparatus.
  • the refrigeration cycle apparatus of the present invention is applicable to other apparatuses having heat exchangers, such as a refrigeration apparatus and a hot water dispenser.
  • Fig. 1 is a circuit diagram of an example of a refrigerant circuit of a refrigeration cycle apparatus of Embodiment 1 of the present invention.
  • a refrigeration cycle apparatus 10 includes a refrigerant circuit including a compressor 11, a first heat exchanger 12, an expansion unit 13, and a second heat exchanger 14 connected in sequence to each other via pipes to circulate refrigerant through the refrigerant circuit.
  • the first heat exchanger 12 is provided with a fan 15a configured to send air
  • the second heat exchanger 14 is provided with a fan 15b configured to send air.
  • first heat exchanger 12 and the second heat exchanger 14 are each referred to as a "heat exchanger 1" when the first heat exchanger 12 and the second heat exchanger 14 are not distinguished from each other.
  • 1,1,2-trifluoroethylene (HFO-1123) having a single double bond in a molecular structure or a refrigerant mixture containing HFO-1123 is used.
  • HFC hydrofluorocarbon
  • HFC-410A hydrofluorocarbon refrigerant
  • ODP ozone depletion potential
  • HFC refrigerants have the probability of causing global warming, and have a high GWP value, which is an indication of such a probability.
  • refrigerant having a low GWP includes HFC-32 having a lower GWP than that of HFC-410A.
  • a discharge temperature at an outlet of the compressor 11 is higher than that of the conventional refrigerant, and for this reason, for example, a material resistant to a high temperature needs to be used.
  • the refrigerant having a low GWP includes hydrofluoroolefin (HFO) having a carbon double bond in a composition and readily decomposed by an OH radical in the atmosphere.
  • HFO refrigerant examples include HFO-1234yf and HFO-1234ze.
  • these refrigerants have a high standard boiling point, and thus, the pressure of these refrigerants is lower than that at a saturation temperature equivalent to that in the case of the conventional refrigerant.
  • a refrigerant density is lower than that of the conventional HFC refrigerant, and the frequency of the compressor 11 needs to be increased to maintain the flow rate of refrigerant circulating in the refrigeration cycle apparatus 10 at a flow rate equivalent to that of the conventional refrigerant.
  • power consumption increases, leading to a lower energy saving performance.
  • HFO-1123 or a refrigerant mixture containing HFO-1123 is used as the refrigerant circulating in the refrigerant circuit in Embodiment 1.
  • HFO-1123 has a low standard boiling point, and thus, the pressure of the refrigerant is higher than that at the saturation temperature equivalent to that in the case of the conventional HFC refrigerant. That is, a refrigerant density is higher than that of the conventional refrigerant, and the flow rate of refrigerant circulating in the refrigeration cycle apparatus 10 can be maintained at the flow rate equivalent to that of the conventional refrigerant even when the frequency of the compressor 11 is decreased.
  • HFO-1123 has excellent energy saving performance. Moreover, HFO-1123 has greater latent heat than that of the conventionally-used HFC-410A, and thus, the flow rate of refrigerant circulating in the refrigeration cycle apparatus 10 can be decreased. That is, the refrigeration cycle apparatus 10 in which HFO-1123 is used as working fluid is capable of reducing a pressure loss in a flat tube 2 (a heat transfer pipe) in the heat exchanger 1 and producing a heat transfer (cooling energy) capacity equivalent to that in the case of using the conventional refrigerant.
  • the compressor 11 is configured to compress refrigerant discharged from the second heat exchanger 14 to supply high-temperature high-pressure refrigerant to the first heat exchanger 12.
  • the first heat exchanger 12 acts as a condenser to exchange heat between air supplied from the fan 15a and the refrigerant, thereby condensing and liquefying the refrigerant.
  • the expansion unit 13 includes an expansion valve, a capillary tube, a pressure reduction device, or an expansion device, for example.
  • the expansion unit 13 is configured to expand the refrigerant discharged from the first heat exchanger 12 into low-temperature low-pressure refrigerant to supply the refrigerant to the second heat exchanger 14.
  • the second heat exchanger 14 acts as an evaporator to exchange heat between air supplied from the fan 15b and the refrigerant, thereby evaporating and gasifying the refrigerant.
  • a flow switching device such as a four-way valve may be provided to switch a flow direction of refrigerant in the refrigerant circuit to cause the first heat exchanger 12 to act as the evaporator and the second heat exchanger 14 to act as the condenser.
  • Fig. 2 is a perspective view of an example of the heat exchanger of the refrigeration cycle apparatus of Embodiment 1 of the present invention.
  • the heat exchanger 1 includes a plurality of flat tubes 2, a plurality of fins 3, and a pair of headers 4a and 4b.
  • the plurality of fins 3 are arranged at intervals to allow fluid such as air to flow through the intervals.
  • the plurality of flat tubes 2 are inserted into the plurality of fins 3.
  • a direction along a longitudinal dimension of a flat cross section of each of the plurality of flat tubes 2 (hereinafter referred to as a "long-axis direction”) is in a direction of air flowing between adjacent ones of the fins 3, and the plurality of flat tubes 2 are arranged at intervals in a direction along a thickness dimension of the flat cross section (hereinafter referred to as a "short-axis direction").
  • the headers 4a and 4b extend in the vertical direction, and are arranged to face each other.
  • the headers 4a and 4b are each connected to a corresponding one of both ends of each flat tube 2.
  • Refrigerant having flowed into the header 4a is branched in the header 4a, and then, flows into each flat tube 2.
  • the refrigerant circulating in a refrigerant passage of each flat tube 2 exchanges heat with air flowing between adjacent ones of the plurality of fins 3 and between adjacent ones of the plurality of flat tubes 2, and then, flows into the header 4b.
  • the refrigerant having flowed into the header 4b is joined in the header 4b and then flows out from the header 4b.
  • headers 4a and 4b are illustrated as being elongated in the vertical direction, and refrigerant flows toward the flat tubes 2 in the horizontal direction in the drawing; however, the direction of the headers 4a and 4b is not limited to such a direction.
  • the headers 4a and 4b may be placed in a landscape orientation, and refrigerant may flow in the vertical direction.
  • a branched pipe for branching refrigerant may be provided instead of at least one of the headers 4a and 4b.
  • the fins 3 are made of aluminum, for example. Each fin 3 is formed into an arbitrary shape by, for example, cutting an aluminum bar into a predetermined size and then pressing or processing the aluminum bar. Note that the material of the fin 3 is not limited to aluminum, and an arbitrary material such as copper can be used. Moreover, the shape of the fin 3 may be an arbitrary shape such as a plate-shaped plate fin and a corrugated fin formed in a wave shape. Further, the fin 3 may be formed in a shape having improved heat exchange performance by, for example, cutting and raising processing or formation of a recessed-raised portion.
  • Fig. 3 is a cross-sectional view of an example of the flat tube of the refrigeration cycle apparatus of Embodiment 1 of the present invention.
  • the flat tube 2 has a flat cross section.
  • the flat tube 2 includes a flat perforated tube, and a plurality of passages 21 divided by partition walls 20 are formed along the longitudinal direction of the flat tube 2.
  • the flat tube 2 is made of aluminum, for example.
  • brazing can be used for bonding the fins 3 and the flat tubes 2.
  • an adhesive may be used for bonding the fins 3 and the flat tubes 2. In the case where the fins 3 and the flat tubes 2 are bonded together by brazing using a brazing material such as an aluminum brazing material, adhesion among the fins 3 and the flat tubes 2 is better than that in the case of using the adhesive.
  • bonding the fins 3 and the flat tubes 2 by brazing can, as compared to a tube expansion method in which bonding is made by expansion of the tube inserted into the fin 3, provide the heat exchanger 1 having a higher heat transfer performance and excellent heat exchange performance.
  • Fig. 4 is a cross-sectional view of an example of the heat exchanger of the refrigeration cycle apparatus of Embodiment 1 of the present invention.
  • the flat tubes 2 are arranged in two columns in a column direction, which is the direction of air flow. Moreover, the plurality of flat tubes 2 are arranged in a row direction perpendicular to the column direction. Further, the flat tubes 2 of adjacent columns do not overlap with each other in the row direction (for example, a zig-zag pattern). Air flows from a side of parts of the fins 3 at an upstream side of the flat tubes 2.
  • Each flat tube 2 has the thickness dimension (hereinafter referred to as a "short-axis diameter DA") in the flat cross section of 2.0 mm and the longitudinal dimension (hereinafter referred to as a "long-axis diameter DB”) in the flat cross section of 19.0 mm, for example.
  • the number of holes of the passages 21 is 20 and the thickness TI of the partition wall 20 of the passage 21 is 0.20 mm, for example.
  • a wall thickness TO between an outer wall of the flat tube 2 and an inner wall of the passage 21 is 0.30 mm.
  • a row pitch DP which is a distance in the row direction between the centers of adjacent ones of the flat tubes 2, is 13.6 mm.
  • Each fin 3 has a width L in the direction of air flow of 22 mm.
  • the heat exchanger 1 has a height H_HEX of 600 mm and a fin stack width H_W of 850 mm (see Fig. 2 ).
  • Fig. 5 is a characteristic graph of a relationship between the short-axis diameter DA of the flat tube and a coefficient of performance (COP) in the refrigeration cycle apparatus of Embodiment 1 of the present invention.
  • Fig. 5 shows a result obtained by simulation of the coefficient of performance (COP) for each short-axis diameter DA using the short-axis diameter DA of the flat tube 2 as a parameter when the heat exchanger 1 is used as the evaporator as an example. Moreover, Fig. 5 shows comparison between the case of using HFC-410A as the refrigerant circulating in the refrigerant circuit and the case of using HFO-1123 as the refrigerant circulating in the refrigerant circuit.
  • COP coefficient of performance
  • an aspect ratio B/A which is a ratio between the inner length B of the passages 21 in the long-axis direction of the flat tube 2 and the inner length A of the passages 21 in the short-axis direction of the flat tube 2, is a preset constant value.
  • the aspect ratio B/A is equivalent to that of the above-described dimension example. That is, in the above-described dimension example, the inner length B of the passages 21 is 0.73 mm, and the inner length A of the passages 21 is 1.4 mm.
  • the aspect ratio B/A is 0.52.
  • a ratio between the row pitch DP of the flat tubes 2 and the short-axis diameter DA of the flat tube 2 is a preset constant value.
  • a ratio is equivalent to that of the above-described dimension example. That is, DP/DA is 6.8, for example.
  • a ratio between the wall thickness TO and the short-axis diameter DA of the flat tube 2 is a preset constant value.
  • such a ratio is equivalent to that of the above-described dimension example. That is, TO/DA is 0.15, for example.
  • the long-axis diameter DB of the flat tube 2 and the height H_HEX and the fin stack width H_W of the heat exchanger 1 are equivalent to those of the above-described dimension example.
  • the amount of heat transferred from the fins 3 and the flat tube 2 (a received heat amount) is constant.
  • other parameters of the heat transfer pipe and the heat exchanger 1 than above such as the pitch of the fins 3, the number of holes, and a path configuration of the heat exchanger 1, and operation conditions in a refrigeration cycle are values when the coefficient of performance is substantially optimal.
  • the short-axis diameter DA of the flat tube 2 is extremely small, the cross-sectional area of each passage 21 of the flat tube 2 is narrowed, and thus, a pressure loss in the tube increases.
  • the number of paths of the heat exchanger 1 needs to be increased.
  • the refrigerant needs to be equally distributed by the headers 4a and 4b for sufficient performance.
  • the short-axis diameter DA of the flat tube 2 is extremely small, refrigerant is difficult to be equally distributed.
  • the upper limit of the number of paths is determined depending on the size of the heat exchanger 1.
  • the pressure loss in the flat tube 2 is smaller in the case of using HFO-1123 as refrigerant flowing through the flat tube 2 than in the case of HFC-410A.
  • the number of paths can be reduced, and the coefficient of performance is improved.
  • the coefficient of performance in the case of using HFO-1123 as refrigerant is substantially equal to or higher than a peak value of the coefficient of performance in the case of HFC-410A.
  • sufficient performance can be exhibited.
  • the inner length B of the passage 21 in the long-axis direction of the flat tube 2 is 0.33 mm, for example.
  • the size of sludge caused due to chemical reaction of a decomposition product of HFO-1123 is about 0.15 mm.
  • the short-axis diameter DA of the flat tube 2 is set to satisfy a relationship of 0.9 mm ⁇ DA ⁇ 3.0 mm. Consequently, heat transfer performance of the heat exchanger 1 can be improved in the case of using HFO-1123 or the refrigerant mixture containing HFO-1123 as refrigerant circulating in the refrigerant circuit, and a reduction in reliability can be suppressed even when sludge is caused due to refrigerant decomposition.
  • the aspect ratio B/A when a smaller value is selected as the aspect ratio B/A, the inner length B of the passage 21 in the long-axis direction of the flat tube 2 is not sufficient, and the pressure loss in the tube increases. For this reason, in the case of a small short-axis diameter DA as described above, such a diameter is typically increased depending on the aspect ratio to such an extent that pressure resistance performance is maintained.
  • the short-axis diameter DA of the flat tube 2 is 1.0 mm ⁇ DA ⁇ 1.8 mm
  • the coefficient of performance in the case of using HFO-1123 as refrigerant flowing through the flat tube 2 is within 2% of a maximum value.
  • the short-axis diameter DA of the flat tube 2 is set to satisfy a relationship of 1.0 mm ⁇ DA ⁇ 1.8 mm so that excellent performance can be particularly exhibited.
  • Embodiment 1 in the case of using HFO-1123 or the refrigerant mixture containing HFO-1123 as refrigerant circulating in the refrigerant circuit, the heat transfer performance of the heat exchanger 1 can be improved. Moreover, the refrigeration cycle apparatus 10 can be provided, with which a reduction in the reliability can be suppressed even when sludge is caused due to refrigerant decomposition.
  • Fig. 6 is a cross-sectional view of an example of a flat tube of a refrigeration cycle apparatus of Embodiment 2 of the present invention.
  • Fig. 7 is an enlarged cross-sectional view of the example of the flat tube of the refrigeration cycle apparatus of Embodiment 2 of the present invention.
  • a flat tube 2 of Embodiment 2 is configured so that one or more protrusions 22 are formed in a passage direction on each inner wall surface of each passage 21. Note that, in the example of Fig. 7 , the case where two-phase gas-liquid refrigerant flows is illustrated, "25" indicates a two-phase flow liquid film, and "26" indicates a gas-liquid interface.
  • a contact area between the inner wall surface of the passage 21 and refrigerant can be increased. Moreover, disturbance of the flow of refrigerant in the passage 21 can be promoted. Further, as illustrated in Fig. 7 , liquid refrigerant is concentrated on a bottom portion 24 of each protrusion 22 due to surface tension of refrigerant. Consequently, drainability in a tube axial direction can be improved, and the thickness of the two-phase flow liquid film 25 around the bottom portion 24 of the protrusion 22 can be reduced. Thus, heat can be more efficiently exchanged than that of the case where the protrusions 22 are provided.
  • the protrusion 22 has a triangular cross-sectional shape, but the present invention is not limited to such a shape.
  • the protrusion 22 has any cross-sectional shapes such as a semicircular shape, an oval shape, and a rectangular shape, an advantageous effect similar to the above-described purpose can be obtained.
  • sludge 31 caused in decomposition of HFO-1123 tends to be accumulated between adjacent ones of the protrusions 22, for example.
  • the sludge 31 tends to be accumulated on a lower one of the inner wall surfaces 23 of the passage 21 of the flat tube 2 in the direction of gravitational force.
  • Such sludge 31 accumulated in the passage 21 leads to an increase in a pressure loss in the tube or clogging.
  • a pressure in a refrigerant circuit increases more than necessary, and for this reason, reliability may be lowered.
  • the size of sludge caused due to chemical reaction of a decomposition product of HFO-1123 is smaller than 0.15 mm.
  • a distance D between adjacent ones of the protrusions 22 are set to satisfy 0.15 mm ⁇ D so that refrigerant can flow without accumulation of the sludge 31 in the passage 21.
  • the pressure loss in the tube can be reduced by increasing the distance D between adjacent ones of the protrusions 22.
  • the distance D between adjacent ones of the protrusions 22 becomes too large, the incremental modulus of a heat transfer area of the inner wall surface of the passage 21 decreases. Further, disturbance of the flow of refrigerant in the passage 21 cannot be sufficiently promoted.
  • the distance D between adjacent ones of the protrusions 22 is preferably equal to or shorter than 0.50 mm.
  • the distance D between adjacent ones of the protrusions 22 is set to satisfy a relationship of 0.15 mm ⁇ D ⁇ 0.50 mm.
  • Fig. 9 is a cross-sectional view of an example of the flat tube of the refrigeration cycle apparatus of Embodiment 2 of the present invention.
  • Fig. 10 is an enlarged cross-sectional view of the example of the flat tube of the refrigeration cycle apparatus of Embodiment 2 of the present invention.
  • a single protrusion 22 is provided on a lower one of inner wall surfaces 23 of a passage 21 in the direction of gravitational force, and a single protrusion 22 is provided on an upper one of the inner wall surfaces of the passage 21 in the direction of gravitational force.
  • the number of protrusions 22 is not limited to such an example, and a plurality of protrusions 22 may be provided on a single inner wall surface. Note that, in the case of providing the plurality of protrusions 22, a distance D between these protrusions 22 is set to satisfy the above-described relationship.
  • sludge 31 caused in decomposition of HFO-1123 tends to be accumulated between the protrusion 22 and a side wall of the passage 21.
  • the sludge 31 tends to be accumulated on a lower one of the inner wall surfaces 23 of the passage 21 of a flat tube 2 in the direction of gravitational force.
  • a distance C from a bottom portion 24 of the protrusion 22 to the side wall of the passage 21 is set to satisfy 0.15 mm ⁇ C so that refrigerant can flow without accumulation of the sludge 31 in the passage 21.
  • the distance C is preferably equal to or shorter than 0.50 mm.
  • the distance C from the bottom portion 24 of the protrusion 22 to the side wall of the passage 21 is set to satisfy a relationship of 0.15 mm ⁇ D ⁇ 0.50 mm.
  • Fig. 11 is a characteristic graph of a relationship between pressure resistance performance and a ratio between a wall thickness TO and a short-axis diameter DA of a flat tube in a refrigeration cycle apparatus of Embodiment 3 of the present invention.
  • HFO-1123 In the case of using HFO-1123 or a refrigerant mixture containing HFO-1123 as refrigerant flowing through a refrigerant circuit, HFO-1123 has a lower standard boiling point than that of conventionally-used HFC-410A. Thus, a pressure is higher than that at a saturation temperature equivalent to the case of HFC-410A. For this reason, sufficient pressure resistance performance of a flat tube 2 needs be to ensured.
  • the wall thickness TO and the short-axis diameter DA of the flat tube 2 are used as parameters under calculation conditions in simulation of a coefficient of performance as shown in Fig. 5 of Embodiment 1 described above.
  • the horizontal axis represents the ratio TO/DA between the wall thickness TO and the short-axis diameter DA of the flat tube 2
  • the vertical axis represents a ratio Pr/Pn between the pressure resistance performance Pr of the flat tube 2 and required pressure resistance Pn of the flat tube 2.
  • TO/DA and Pr/Pn are in a proportional relationship. That is, regardless of an absolute value of the short-axis diameter DA of the flat tube 2, a decrease in TO/DA results in a decrease in the value of Pr/Pn.
  • a ratio of the wall thickness TO to the short-axis diameter DA decreases with a decrease in TO/DA, a cross-sectional area of a passage 21 and a heat transfer area of the passage 21 increase, and heat exchange performance is also enhanced.
  • the ratio of the wall thickness TO to the short-axis diameter DA decreases with a decrease in TO/DA, the pressure resistance performance Pr is lowered, and Pr/Pn decreases.
  • the pressure resistance performance Pr needs to exceed the required pressure resistance Pn. That is, when Pr/Pn is equal to or smaller than one, sufficient pressure resistance performance cannot be ensured. For this reason, Pr/Pn > 1 needs to be satisfied. In the example shown in Fig. 11 , when TO/DA falls below 0.10, Pr/Pn is equal to or smaller than one. Thus, a relationship of 0.10 ⁇ TO/DA needs to be satisfied. On the other hand, when TO/DA extremely increases, sufficient pressure resistance performance is ensured. However, the cross-sectional area and the heat transfer area of the passage 21 decreases, and the heat exchange performance is also lowered.
  • TO/DA is preferably 0.10 ⁇ TO/DA ⁇ 0.20.
  • the present invention is not limited to the air-conditioning apparatus, and a similar advantageous effect can be also obtained in the case where the present invention is applied to the refrigeration cycle apparatus 10 in which the above-described heat exchanger 1 is used as at least one of the first heat exchanger 12 and the second heat exchanger 14 in the refrigerant circuit formed by connecting at least the compressor 11, the first heat exchanger 12, the expansion unit 13, and the second heat exchanger 14 in sequence to each other via pipes.
  • Reference Signs List is not limited to the air-conditioning apparatus, and a similar advantageous effect can be also obtained in the case where the present invention is applied to the refrigeration cycle apparatus 10 in which the above-described heat exchanger 1 is used as at least one of the first heat exchanger 12 and the second heat exchanger 14 in the refrigerant circuit formed by connecting at least the compressor 11, the first heat exchanger 12, the expansion unit 13, and the second heat exchanger 14 in sequence to each other via pipes.

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Geometry (AREA)
  • Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)
EP14909044.1A 2014-12-26 2014-12-26 Appareil à cycle de réfrigération Withdrawn EP3239640A4 (fr)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/JP2014/084466 WO2016103437A1 (fr) 2014-12-26 2014-12-26 Appareil à cycle de réfrigération

Publications (2)

Publication Number Publication Date
EP3239640A1 true EP3239640A1 (fr) 2017-11-01
EP3239640A4 EP3239640A4 (fr) 2018-09-26

Family

ID=56149530

Family Applications (1)

Application Number Title Priority Date Filing Date
EP14909044.1A Withdrawn EP3239640A4 (fr) 2014-12-26 2014-12-26 Appareil à cycle de réfrigération

Country Status (3)

Country Link
EP (1) EP3239640A4 (fr)
JP (1) JP6415600B2 (fr)
WO (1) WO2016103437A1 (fr)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2018059638A (ja) * 2016-09-30 2018-04-12 株式会社富士通ゼネラル 熱交換器および冷凍サイクル装置
JP2021081081A (ja) * 2019-11-14 2021-05-27 ダイキン工業株式会社 伝熱管、及び、熱交換器
US20230375283A1 (en) * 2020-10-20 2023-11-23 Mitsubishi Electric Corporation Heat exchanger and refrigeration cycle apparatus

Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63116095A (ja) * 1986-10-31 1988-05-20 Matsushita Refrig Co 偏平熱交換器管
JPH06185885A (ja) * 1992-07-24 1994-07-08 Furukawa Electric Co Ltd:The 偏平多穴凝縮伝熱管
JP2000154987A (ja) * 1998-11-19 2000-06-06 Daikin Ind Ltd 空気熱交換器
JP3313086B2 (ja) * 1999-06-11 2002-08-12 昭和電工株式会社 熱交換器用チューブ
JP2001165532A (ja) * 1999-12-09 2001-06-22 Denso Corp 冷媒凝縮器
JP2002318086A (ja) * 2001-04-16 2002-10-31 Japan Climate Systems Corp 熱交換器用チューブ
JP2009063228A (ja) * 2007-09-06 2009-03-26 Showa Denko Kk 扁平状伝熱管
JP2010255864A (ja) * 2009-04-21 2010-11-11 Showa Denko Kk 扁平管および熱交換器
JP2012102969A (ja) * 2010-11-12 2012-05-31 Showa Denko Kk 蓄冷機能付きエバポレータ
WO2012157764A1 (fr) * 2011-05-19 2012-11-22 旭硝子株式会社 Fluide moteur, et système à cycle thermique
CN102269536A (zh) * 2011-08-17 2011-12-07 三花丹佛斯（杭州）微通道换热器有限公司 用于换热器的扁管以及具有该扁管的换热器
WO2014203353A1 (fr) * 2013-06-19 2014-12-24 三菱電機株式会社 Climatiseur

Also Published As

Publication number Publication date
JPWO2016103437A1 (ja) 2017-04-27
EP3239640A4 (fr) 2018-09-26
WO2016103437A1 (fr) 2016-06-30
JP6415600B2 (ja) 2018-10-31

Similar Documents

Publication Publication Date Title
JP4738401B2 (ja) 空気調和機
JP6851492B2 (ja) 管支持構造を有する凝縮器
EP3021064B1 (fr) Dispositif de pompe à chaleur
EP3205967B1 (fr) Échangeur thermique et dispositif de climatisation
CN102016482B (zh) 热交换器以及使用该热交换器的空调机
US20180106563A1 (en) Heat exchanger and refrigeration cycle apparatus
EP3315876B1 (fr) Échangeur de chaleur et dispositif à cycle de réfrigération pourvu d'un échangeur de chaleur
CN102455087B (zh) 集管单元和具有该集管单元的热交换器
WO2014147788A1 (fr) Échangeur de chaleur, dispositif à cycle de réfrigération, et méthode de production pour échangeur de chaleur
WO2011086881A1 (fr) Tube de transfert de chaleur pour échangeur de chaleur, échangeur de chaleur, dispositif à cycle de réfrigération et dispositif de climatisation
JP2010038502A (ja) 熱交換器用の伝熱管、熱交換器、冷凍サイクル装置及び空気調和装置
CN102563979A (zh) 热交换器
JPWO2014181400A1 (ja) 熱交換器及び冷凍サイクル装置
EP3239640A1 (fr) Appareil à cycle de réfrigération
EP3062037B1 (fr) Échangeur thermique et dispositif à cycle de réfrigération utilisant ledit échangeur thermique
JP2005195192A (ja) 内面溝付伝熱管
JP6053693B2 (ja) 空気調和機
EP4155646A1 (fr) Échangeur de chaleur, unité extérieure et dispositif à cycle de réfrigération
JPWO2020012549A1 (ja) 熱交換装置、熱交換器ユニット及び冷凍サイクル装置
JP5646257B2 (ja) 冷凍サイクル装置
JP2008309443A (ja) 伝熱管接続構造
US11965701B2 (en) Heat exchanger and refrigeration cycle apparatus
EP3971507A1 (fr) Échangeur de chaleur, et dispositif de cycle frigorifique
JP2003004396A (ja) 熱交換器および冷凍空調装置
JP2003185361A (ja) 接触型熱交換器及びそれを用いたヒートポンプ式給湯装置

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

17P Request for examination filed

Effective date: 20170413

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

AX Request for extension of the european patent

Extension state: BA ME

DAX Request for extension of the european patent (deleted)
A4 Supplementary search report drawn up and despatched

Effective date: 20180827

RIC1 Information provided on ipc code assigned before grant

Ipc: F25B 1/00 20060101ALI20180821BHEP

Ipc: F28F 1/02 20060101AFI20180821BHEP

Ipc: F28D 21/00 20060101ALI20180821BHEP

Ipc: F28D 1/053 20060101ALI20180821BHEP

17Q First examination report despatched

Effective date: 20190131

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

Free format text: STATUS: THE APPLICATION HAS BEEN WITHDRAWN

18W Application withdrawn

Effective date: 20190409