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
  • F25B47/00—Arrangements for preventing or removing deposits or corrosion, not provided for in another subclass
  • F25B47/02—Defrosting cycles
• • 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
• • 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
  • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
  • F28F1/00—Tubular elements; Assemblies of tubular elements
  • F28F1/10—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses
  • F28F1/12—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses the means being only outside the tubular element
  • F28F1/24—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses the means being only outside the tubular element and extending transversely
  • F28F1/30—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses the means being only outside the tubular element and extending transversely the means being attachable to the element
• • 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
  • F28F1/10—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses
  • F28F1/12—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses the means being only outside the tubular element
  • F28F1/24—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses the means being only outside the tubular element and extending transversely
  • F28F1/32—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses the means being only outside the tubular element and extending transversely the means having portions engaging further tubular elements

Definitions

• FIG. 11 is a schematic plan view of a portion of a heat exchanger according to a fourth embodiment.
• FIG. 13 is a schematic plan view of a portion of a heat exchanger according to embodiment 6.
• FIG. 23 is a schematic plan view of a first example of a portion of a heat exchanger according to embodiment 7.
• a schematic plan view of a portion of a heat exchanger according to embodiment 10 A schematic cross-sectional view of a flat portion of a corrugated fin of a heat exchanger according to embodiment 10, cut in the air flow direction.
• a schematic plan view of a portion of a heat exchanger according to embodiment 12. A diagram showing the configuration of an air conditioning device pertaining to embodiment 13.
• FIG. 1 is a diagram illustrating the configuration of a heat exchanger 10 according to a first embodiment. Arrows in Fig. 1 indicate the flow of refrigerant when the heat exchanger 10 is used as an evaporator. When the heat exchanger 10 is used as an evaporator, a low-temperature and low-pressure refrigerant flows through the refrigerant flow passage in the flat heat transfer tube 1. When the heat exchanger 10 is used as a condenser, a high-temperature and high-pressure refrigerant flows through the refrigerant flow passage in the flat heat transfer tube 1.
• the pair of headers 3 are each connected to other devices that make up the air conditioning system 90 (see Figure 28), and are pipes through which the refrigerant, a fluid that serves as a heat exchange medium, flows in and out, and through which the refrigerant branches or merges.
• the pair of headers 3 have a first header 3A and a second header 3B.
• the first header 3A and the second header 3B are arranged with a gap between them vertically.
• the pipe axis direction Z is the up-down direction of the heat exchanger 10.
• the direction perpendicular to the "pipe arrangement direction X" and the "pipe axis direction Z" is referred to as the "air flow direction Y".
• air flow direction Y air flows in the direction of the white arrow (see FIG. 2 to FIG. 4) described later.
• Each flat heat transfer tube 1 is arranged standing vertically.
• the through holes of the flat heat transfer tubes 1 extend vertically and are connected to a pair of headers 3.
• the flat heat transfer tubes 1 are arranged so that the longer sides of their flat cross sections are aligned with the air flow direction Y.
• Each flat heat transfer tube 1 is joined to the pair of headers 3 by inserting both ends of the flat heat transfer tube 1 into insertion holes (not shown) formed in each of the pair of headers 3 and brazing them.
• a brazing material containing aluminum is used for the brazing.
• the material of the fin material that constitutes the corrugated fin 2 is, for example, an aluminum alloy.
• the surface of the fin material that constitutes the corrugated fin 2 is then clad with a brazing material layer.
• the main material of the clad brazing material layer is, for example, an aluminum-silicon-based brazing material that contains aluminum.
• the plate thickness of the fin material that constitutes the corrugated fin 2 is, for example, about 50 ⁇ m to 200 ⁇ m.
• the corrugated fin 2 has a configuration in which plate-shaped fin portions 24 are connected in a wave-like manner in the tube axis direction Z.
• the corrugated fin 2 When viewed in the air flow direction Y, the corrugated fin 2 has a shape in which the fin portions 24 are connected in the tube axis direction Z with alternating inclinations in opposite directions.
• the fin portions 24 have a flat plate portion 21 and curved apex portions 20 at both ends of the flat plate portion 21 in the tube arrangement direction X.
• the corrugated fin 2 is joined to the flat heat transfer tube 1 at the apex portion 20 in surface contact with the flat surface 1a of the flat heat transfer tube 1.
• the fin portion 24 has a number of louvers 22 arranged in the air flow direction Y.
• the louvers 22 have louver slits 22a that allow air to pass through, and plate portions 22b that guide air to the louver slits 22a.
• the plate portions 22b are inclined with respect to the flat plate portion 21.
• the louver slits 22a and the plate portions 22b are configured in a rectangular shape extending in the pipe arrangement direction X.
• the louvers 22 are formed by cutting and raising the plate portions 22b from the flat plate portion 21.
• the multiple louvers 22 are divided into a first louver group 22A formed upstream in the air flow direction Y of drainage slits 23 (described below) formed in the fin portion 24, and a second louver group 22B formed downstream in the air flow direction Y of the drainage slits 23.
• the drainage slits 23 are openings that allow water that accumulates on the upper surface of the fin portion 24, especially on the flat plate portion 21 that is close to horizontal, to fall to the lower surface.
• the fin portion 24 is formed with drainage slits 23 for draining condensation water 4 formed on the fin portion 24.
• the drainage slits 23 are through holes formed in the corrugated fin 2. Under low temperature outside air conditions, moisture in the air condenses, forming condensation water 4 on the surfaces of the flat heat transfer tube 1 and the corrugated fin 2. The condensation water 4 formed on the surface of the fin portion 24 of the corrugated fin 2 flows down from the drainage slits 23 to the lower fin portion 24.
• the drainage slit 23 is formed in a rectangular shape extending longitudinally in the pipe arrangement direction X, i.e., in a direction perpendicular to the air flow direction Y.
• the drainage slit 23 is formed in the center of the fin portion 24 in the air flow direction Y, but the position where the drainage slit 23 is formed is not limited to the center.
• the areas between the multiple rows of drainage slits 23 are typically flat, similar to the flat plate portion 21.
• a flat area may also be formed between the drainage slit 23 located most upstream in the air flow direction Y and the first louver group 22A, and between the drainage slit 23 located most downstream in the air flow direction Y and the second louver group 22B, similar to the flat plate portion 21.
• the number of rows of drainage slits 23 is synonymous with the number of drainage slits 23, and hereinafter the number of drainage slits 23 will be indicated using either the expression "number of rows" or "number”.
• FIG. 4 is a schematic plan view of a portion of the heat exchanger 10 according to the first embodiment.
• FIG. 4 shows the heat exchanger 10 as viewed in the tube axis direction Z of the flat heat transfer tubes 1.
• the white arrows in FIG. 4 indicate the air flow direction.
• the corrugated fin 2 will be described in more detail with reference to FIG. 4. Note that the drainage slits 23 are not shown in FIG. 4.
• the corrugated fin 2 has a front edge 2b, which is the tip of the corrugated fin 2 on the windward side with respect to the flow of air that flows between adjacent flat heat transfer tubes 1 among the flat heat transfer tubes 1 in the air flow direction Y.
• the heat exchanger 10L according to the comparative example is a device in which the front edge 2b of the fin portion 24 does not protrude upwind relative to the air flow in the air flow direction Y.
• the horizontal axis indicates the fin length L- F of the fin portion 24, and the vertical axis indicates temperature (°C).
• the solid line A in (b) indicates the surface temperature of the fin portion 24, and the dashed line B indicates the temperature of the air around the heat exchanger 10L.
• Part A1 in (b) indicates the position of the front edge 2b of the fin portion 24, and part A2 indicates the position of the rear edge 2c.
• FIG. 7 is a diagram showing the relationship between the protrusion length ratio ( Lt / LF ) of the fin portion 24 and the heating low-temperature capacity (%).
• frost forms on the corrugated fins of the heat exchanger when the heat exchanger is operated for heating under environmental conditions of low outside air temperature.
• the heating capacity decreases, so the heat exchanger switches from heating operation to defrosting operation.
• the heat exchanger cannot perform heating or the heating capacity decreases.
• defrosting operation melts frost by flowing a refrigerant at a temperature higher than 0°C through the heat exchanger, and the fan is usually stopped during this operation.
• the inventors focused on the protrusion length ratio ( Lt /L F ) of the fin portions 24.
• the inventors conducted an experiment on corrugated fins 2 with different protrusion lengths of the fin portions 24, in which after a certain amount of frost had formed, a defrosting operation was performed under conditions of an outside air temperature of about 0°C and a certain wind speed, and the time required for defrosting (the time until the frost has almost disappeared visually) was measured.
• the heating low-temperature capacity can be significantly improved when the protrusion length ratio ( Lt / LF ) of the fin portion 24 is in the range of greater than 0 and less than 0.22.
• the protrusion length ratio ( Lt / LF ) of the fin portion 24 is 0.22 or more, there is almost no improvement in the heating low-temperature capacity, and residual frost is likely to occur.
• the fin portion 24 of the heat exchanger 10 includes a leading edge protrusion 2a that constitutes a portion extending to the windward side from the brazed portion 10a of the windwardmost portion between the flat heat transfer tubes 1 and the corrugated fins 2.
• the heat exchanger 10 is configured so that the relationship between the fin portion 24 and the flat heat transfer tubes 1 of Lt /L F satisfies the formula 0 ⁇ Lt /L F ⁇ 0.22.
• the heat exchanger 10 is configured such that the relationship between the fin portion 24 and the flat heat transfer tubes 1 of Lt /L F satisfies the formula 0.06 ⁇ Lt /L F ⁇ 0.22.
• the heat exchanger 10 can improve the frost resistance while suppressing remaining ice at the tip of the fin portion 24 even during defrosting operation, and can improve the heating low-temperature capacity.
• the heating operation capacity of the heat exchanger 10 when Lt /L F is 0.06 is improved by at least 10% compared to the heating operation capacity when Lt /L F is 0.
• FIG. 8 is a schematic cross-sectional view of the flat plate portion 21 of the corrugated fin 2 of the heat exchanger 10 according to the second embodiment, cut in the air flow direction Y.
• FIG. 9 is a schematic cross-sectional view of the flat plate portion 21 of the corrugated fin 2 of the heat exchanger 10M according to the comparative example, cut in the air flow direction Y.
• the second embodiment further specifies the configuration of the louvers 22.
• the white arrows in FIG. 8 and FIG. 9 indicate the direction in which the air flows.
• the dashed arrows in FIG. 8 and FIG. 9 indicate an example of the direction in which the condensed water 4 flows.
• the second embodiment will be described, but the description of the same parts as in the first embodiment will be omitted, and the same reference numerals will be used for the same or corresponding parts as in the first embodiment.
• FIG. 12 is a schematic plan view of a part of the heat exchanger 10 according to the fourth embodiment.
• FIG. 13 is a schematic cross-sectional view of the flat plate portion 21 of the corrugated fin 2 of the heat exchanger 10 according to the fourth embodiment cut in the air flow direction Y.
• the fourth embodiment further specifies the configuration of the leading edge protrusion 2a.
• the white arrows in FIG. 12 and FIG. 13 indicate the direction in which the air flows.
• the dashed arrows in FIG. 12 and FIG. 13 indicate an example of the direction in which the condensed water 4 flows.
• the fourth embodiment will be described, but descriptions of parts that overlap with the first to third embodiments will be omitted, and the same reference numerals will be used for the same or corresponding parts as the first to third embodiments.
• the front edge protrusion 2a of the heat exchanger 10 in embodiment 4 includes a first edge fold 2a1 that is bent toward the upper surface side of the fin portion 24 and overlapped on the flat plate portion 21.
• the hatched portion indicates the first edge fold 2a1.
• the edge of the first edge fold 2a1 forms a step 2a2 with respect to the flat plate portion 21.
• the first edge fold 2a1 is a portion where the plate-like member that constitutes the fin portion 24 is overlapped upwardly with respect to the flat plate portion 21.
• the corrugated fin 2 has the first edge fold 2a1 at the end on the front edge 2b side in the air flow direction Y.
• the bent portion of the first edge fold 2a1 constitutes the front edge 2b of the fin portion 24.
• the front edge protruding portion 2a of the heat exchanger 10 according to the fourth embodiment includes a first edge folded portion 2a1 folded toward the upper surface side of the fin portion 24 and overlapped with the flat plate portion 21.
• the edge of the first edge folded portion 2a1 forms a step 2a2 with respect to the flat plate portion 21.
• the heat exchanger 10 according to the fourth embodiment has the first edge folded portion 2a1, and by forming the step 2a2 on the front edge protruding portion 2a, it is possible to suppress the condensed water 4 from being guided to the front edge portion 2b and reduce the growth of frost due to outside wind.
• the heat exchanger 10 according to the fourth embodiment forms the first edge folded portion 2a1 by folding the edge of the fin portion 24, and increases the thickness of the plate of the fin portion 24 on the front edge portion 2b side, thereby increasing the thermal conductivity and making it easier to melt the frost on the front edge portion 2b side. Therefore, by having the first edge folded portion 2a1, the heat exchanger 10 of embodiment 4 can improve the frost resistance while suppressing remaining ice at the tips of the fins even during defrosting operation, thereby improving the low-temperature heating capacity.
• the heat exchanger 10 according to the fourth embodiment has the first folded edge portion 2a1, which improves the fin strength of the leading edge protruding portion 2a compared to a case where the heat exchanger does not have this configuration. Also, the heat exchanger 10 has the first folded edge portion 2a1, which makes it possible to increase the thickness of the fin material and improve the strength of the fin tip portion, making it less likely for the corrugated fin 2 to collapse when manufacturing a structure in which the fin portion 24 protrudes upstream, thereby improving manufacturability.
• Fig. 14 is a schematic cross-sectional view of the flat plate portion 21 of the corrugated fin 2 of the heat exchanger 10 according to the fifth embodiment, cut in the air flow direction Y.
• the fifth embodiment further specifies the configuration of the leading edge protrusion 2a.
• the outline arrows in Fig. 14 indicate the direction in which the air flows.
• the dashed arrows in Fig. 14 indicate an example of the direction in which the condensed water 4 flows.
• the fifth embodiment will be described below, but descriptions of parts that overlap with the first to fourth embodiments will be omitted, and the same reference numerals will be used to denote the same or corresponding parts as the first to fourth embodiments.
• the front edge protrusion 2a of the heat exchanger 10 includes a second edge fold 2a3 that is folded toward the underside of the fin portion 24 and overlaps the flat portion 21.
• the edge of the second edge fold 2a3 forms a step 2a2 with respect to the flat portion 21.
• the second edge fold 2a3 is a portion where the plate-like member that constitutes the fin portion 24 is overlapped below the flat portion 21.
• the corrugated fin 2 has the second edge fold 2a3 at the end on the front edge 2b side in the air flow direction Y.
• the folded portion of the second edge fold 2a3 constitutes the front edge 2b of the fin portion 24.
• the edge portion of the second edge fold 2a3 facing inward of the heat exchanger 10 forms the step 2a2.
• the corrugated fin 2 has first edge folds 2a1 and second edge folds 2a3 formed alternately in the tube axis direction Z. That is, the corrugated fin 2 includes a first edge fold 2a1 and a second edge fold 2a3.
• the front edge protrusion 2a of the heat exchanger 10 has at least one drainage slit 23 extending in the pipe arrangement direction X, which allows condensation water 4 (see FIG. 2) on the upper surface of the fin section 24 to fall and be drained.
• the drainage slit 23 is an opening formed in the fin section 24, and is a through hole.
• the number of drainage slits 23 may be one or more.
• the drainage slit 23 is a long opening with a width along the pipe arrangement direction X. At least a portion of the drainage slit 23 is formed on the windward side of the position of the windwardest brazed section 10a. In other words, at least a portion of the drainage slit 23 is formed in the fin section 24 between the position of the front edge 2b and the position of the windwardest brazed section 10a.
• the leading edge protruding portion 2a of the heat exchanger 10 is provided with the convex portion 25 or the concave portion 26, which can suppress the condensation water 4 from flowing to the tip portion of the fin portion 24, and can improve the frost formation resistance while suppressing the generation of residual frost.
• the leading edge protruding portion 2a of the heat exchanger 10 is provided with the convex portion 25 or the concave portion 26, which can improve the fin strength of the leading edge protruding portion 2a compared to a case where the heat exchanger 10 does not have the configuration.
• the rear edge protrusion 2e of the heat exchanger 10 includes a third edge fold 2e1 that is bent toward the upper surface of the fin portion 24 and overlapped with the flat portion 21.
• the hatched portion indicates the third edge fold 2e1.
• the edge of the third edge fold 2e1 forms a step 2e2 with respect to the flat portion 21.
• the third edge fold 2e1 is a portion where the plate-like member that constitutes the fin portion 24 is overlapped upwardly with respect to the flat portion 21.
• the corrugated fin 2 has the third edge fold 2e1 at the end on the rear edge 2c side in the air flow direction Y.
• the bent portion of the third edge fold 2e1 constitutes the rear edge 2c of the fin portion 24.
• the trailing edge protrusion 2e includes a trailing edge side edge fold 2g that is bent toward the upper or lower surface of the fin portion 24 and overlapped with the flat plate portion 21.
• the trailing edge side edge fold 2g that is bent toward the upper surface of the fin portion 24 and overlapped with the flat plate portion 21 is the third edge fold 2e1 (see FIG. 26) described above.
• the trailing edge side edge fold 2g that is bent toward the lower surface of the fin portion 24 and overlapped with the flat plate portion 21 is the fourth edge fold 2e3 (see FIG. 26) described above.
• the edge of the trailing edge side edge fold 2g forms a step 2e2 with respect to the flat plate portion 21.
• Embodiment 13. 28 is a diagram showing the configuration of an air-conditioning apparatus 90 according to embodiment 13.
• Embodiment 13 relates to an air-conditioning apparatus 90 as an example of a refrigeration cycle apparatus equipped with the heat exchanger 10 according to embodiments 1 to 12.
• the air-conditioning apparatus 90 uses the heat exchanger 10 according to embodiments 1 to 12 as an outdoor heat exchanger 230.
• the outdoor heat exchanger 230 exchanges heat between the refrigerant and the outdoor air.
• the outdoor heat exchanger 230 functions as an evaporator, evaporating and vaporizing the refrigerant.
• the outdoor heat exchanger 230 functions as a condenser, condensing and liquefying the refrigerant.
• the outdoor fan 240 sends outdoor air into the outdoor heat exchanger 230, promoting heat exchange in the outdoor heat exchanger 230.
• the refrigerant that flows into the indoor heat exchanger 110 evaporates and gasifies by exchanging heat with the air in the space to be air-conditioned.
• the gasified refrigerant passes through the four-way valve 220 and is sucked into the compressor 210 again.
• the air conditioning device 90 performs air conditioning related to cooling.
• the outdoor fan 240 is stopped, the four-way valve 220 is switched to the same state as during the cooling operation, and the high-temperature, high-pressure gas refrigerant flows into the outdoor heat exchanger 230. This melts the frost adhering to the flat heat transfer tubes 1 and the corrugated fins 2.
• the high-temperature, high-pressure gas refrigerant flows into the flat heat transfer tubes 1 through the header 3 (see FIG. 1). Then, the high-temperature refrigerant flowing into the flat heat transfer tubes 1 melts the frost adhering to the flat heat transfer tubes 1 and the corrugated fins 2 and turns them into water.

Landscapes

• Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• Mechanical Engineering (AREA)
• Thermal Sciences (AREA)
• General Engineering & Computer Science (AREA)
• Geometry (AREA)
• Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)

Priority Applications (3)

Applications Claiming Priority (1)

Publications (1)

Family

ID=93793811

Family Applications (1)

Country Status (2)

Citations (8)

Family Cites Families (5)

• 2024
  • 2024-01-18 WO PCT/JP2024/001185 patent/WO2025154215A1/ja active Pending
  • 2024-01-18 JP JP2024541211A patent/JP7596606B1/ja active Active
  • 2024-11-27 JP JP2024205981A patent/JP2025112266A/ja active Pending

Patent Citations (8)

Also Published As

Similar Documents

Legal Events