CN113217996A - Microchannel heat exchanger and air conditioner - Google Patents
Microchannel heat exchanger and air conditioner Download PDFInfo
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- CN113217996A CN113217996A CN202011445830.7A CN202011445830A CN113217996A CN 113217996 A CN113217996 A CN 113217996A CN 202011445830 A CN202011445830 A CN 202011445830A CN 113217996 A CN113217996 A CN 113217996A
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- 239000003507 refrigerant Substances 0.000 claims abstract description 237
- 238000011144 upstream manufacturing Methods 0.000 claims abstract description 23
- 239000007788 liquid Substances 0.000 claims description 94
- 238000005192 partition Methods 0.000 claims description 4
- 238000010586 diagram Methods 0.000 description 10
- 230000001105 regulatory effect Effects 0.000 description 8
- 230000005484 gravity Effects 0.000 description 5
- 238000001704 evaporation Methods 0.000 description 4
- 230000008020 evaporation Effects 0.000 description 4
- 238000001816 cooling Methods 0.000 description 3
- 238000010438 heat treatment Methods 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 238000009825 accumulation Methods 0.000 description 1
- 239000002826 coolant Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000005057 refrigeration Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000010257 thawing Methods 0.000 description 1
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F1/00—Room units for air-conditioning, e.g. separate or self-contained units or units receiving primary air from a central station
- F24F1/0007—Indoor units, e.g. fan coil units
- F24F1/0059—Indoor units, e.g. fan coil units characterised by heat exchangers
- F24F1/0063—Indoor units, e.g. fan coil units characterised by heat exchangers by the mounting or arrangement of the heat exchangers
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F1/00—Room units for air-conditioning, e.g. separate or self-contained units or units receiving primary air from a central station
- F24F1/06—Separate outdoor units, e.g. outdoor unit to be linked to a separate room comprising a compressor and a heat exchanger
- F24F1/14—Heat exchangers specially adapted for separate outdoor units
- F24F1/16—Arrangement or mounting thereof
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- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Details Of Heat-Exchange And Heat-Transfer (AREA)
- Air Filters, Heat-Exchange Apparatuses, And Housings Of Air-Conditioning Units (AREA)
- Other Air-Conditioning Systems (AREA)
- Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)
Abstract
The invention provides a microchannel heat exchanger and an air conditioner, which can easily distribute refrigerant to a plurality of refrigerant pipes equally by a simple structure. The microchannel heat exchanger according to the embodiment includes a first header constituting an upstream-side flow path, a second header into which a refrigerant from the first header is introduced, a plurality of refrigerant tubes connecting between the first header and the second header, and heat transfer fins joined to the plurality of refrigerant tubes. The microchannel heat exchanger is characterized in that an orifice for increasing the flow rate of the refrigerant flowing through the interior of at least one of the first header and the second header is provided upstream of the plurality of refrigerant tubes connected to the downstream side of the header.
Description
Technical Field
The present invention relates to a microchannel heat exchanger and an air conditioner.
Background
One of the heat exchangers of an air conditioner and the like is a microchannel heat exchanger. Fig. 5 and 6 are diagrams showing a configuration of a conventional microchannel heat exchanger 500. The microchannel heat exchanger 500 includes a refrigerant tube (flat tube) 530 and heat transfer fins 540 joined to the refrigerant tube, and the refrigerant tube (flat tube) 530 includes a plurality of small-diameter flow channels in which microchannels are formed to connect the two header portions 510 and 520.
As shown in fig. 6, the refrigerant R flows in from the lower portion of the header portion 510 in a gas-liquid two-phase state in which the refrigerant vapor and the refrigerant liquid are mixed at the time of evaporation, and is branched into a plurality of (for example, 4 paths) of small-diameter flow paths (see hatched arrows in fig. 5) in the plurality of refrigerant tubes 530. While passing through the small-diameter flow channels, the refrigerant R exchanges heat with the air a (see the hollow arrows in fig. 5) passing through the microchannel heat exchanger 500 via the heat transfer fins 540, evaporates, and flows from the small-diameter flow channels into the header portion 520. In the header portion 520, the refrigerant R in a gas-liquid two-phase state in which the refrigerant vapor and the refrigerant liquid are mixed receives an upward velocity and is distributed around the refrigerant tubes 530 on the upper side, but the refrigerant liquid is distributed while being biased toward the lower side (the direction of gravity, that is, the lower side in the vertical direction) of the header portion 520 by the gravity G. Therefore, when the refrigerant R is branched from the header portion 520 to the small-diameter flow paths in the refrigerant tubes 530 on the downstream side, the refrigerant vapor (the refrigerant R in a gaseous state) flows into the small-diameter flow paths in the refrigerant tubes 530 on the upper side in the vertical direction, and the refrigerant liquid (the refrigerant R in a liquid state) flows into the small-diameter flow paths in the refrigerant tubes 530 on the lower side in the vertical direction in many cases. Therefore, the refrigerant liquid is insufficient in the vertically upper small-diameter flow path having a large temperature difference between the air a and the refrigerant R, and evaporation to dryness occurs. If this evaporation occurs, the evaporative heat transfer performance of the microchannel heat exchanger 500 is reduced as is well known. Further, if the refrigerant liquid enters (stays) downward, there is a possibility that the refrigerant in the refrigerant circuit is insufficient, the pressure becomes low, and frost condenses early. Therefore, in the configuration in which the microchannel heat exchanger 500 is provided in the outdoor unit, heat exchange in the microchannel heat exchanger 500 is inhibited, which causes frequent defrosting operation, and there is a risk that the indoor side is not easily warmed.
Documents of the prior art
Patent document
Patent document 1: japanese patent laid-open publication No. 2013-2688
Disclosure of Invention
Problems to be solved by the invention
In order to suppress the refrigerant flowing into the plurality of refrigerant tubes from deviating to one side, patent document 1 discloses a parallel flow type heat exchanger in which a refrigerant guiding structure is formed in a header pipe. However, in patent document 1, since the heat exchanger in which the internal flow path of the header pipe is processed into a special shape is used, there are problems such as time and labor required for processing the header pipe and cost.
The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a microchannel heat exchanger and an air conditioner that can easily distribute refrigerant equally to a plurality of refrigerant tubes with a simple structure.
Means for solving the problems
The microchannel heat exchanger according to the embodiment includes a first header constituting an upstream-side flow path, a second header into which a refrigerant from the first header is introduced, a plurality of refrigerant tubes connecting between the first header and the second header, and heat transfer fins joined to the plurality of refrigerant tubes. The microchannel heat exchanger is characterized in that an orifice for increasing the flow rate of the refrigerant flowing through the interior of at least one of the first header and the second header is provided upstream of the plurality of refrigerant tubes connected to the downstream side of the header.
Effects of the invention
According to the present invention, the refrigerant can be easily distributed equally to the plurality of refrigerant tubes.
Drawings
Fig. 1 is a diagram showing a configuration of a heat cycle of an air conditioner using a microchannel heat exchanger according to an embodiment.
Fig. 2 is a diagram showing the structure of the header and the refrigerant tubes of the microchannel heat exchanger according to the embodiment.
Fig. 3 is a diagram showing an example of the shape of an orifice used in the microchannel heat exchanger according to the embodiment.
Fig. 4 is a diagram showing a configuration of an air conditioner according to another embodiment.
Fig. 5 is a diagram showing the shape of a general microchannel heat exchanger.
Fig. 6 is a diagram showing the occurrence of refrigerant liquid accumulation in a conventional microchannel heat exchanger.
Description of the reference numerals
100 … air conditioner, 110 … first heat exchanger, 120 … outdoor unit,
130 … first heat exchanger, 140 … indoor unit, 150 … gas-liquid separator
A 160 … compressor (compressor), a 170 … first expansion valve, a 180 … second expansion valve,
190 … the air pressure regulating part,
200. a 300 … micro-channel heat exchanger,
210 … first header, 220 … second header,
230a, 230b …, 240 … fins,
a 250' … first orifice, a 250 "… second orifice, a 260 … flow inlet,
270 … mesh, 280, 290 … upper wall,
295 …, 310 … first block, 320 … second block,
330 … diverter, 340 … common outflow
Detailed Description
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
Fig. 1 is a diagram showing a configuration of a heat cycle of an air conditioner 100 using a microchannel heat exchanger according to an embodiment. The air conditioner 100 includes an outdoor unit 120 having a first heat exchanger 110 and an indoor unit 140 having a second heat exchanger 130. Of the two heat exchangers, at least the first heat exchanger 110 is constituted by a microchannel heat exchanger. In addition, both the first heat exchanger 110 and the second heat exchanger 130 may be configured by microchannel heat exchangers. The outdoor unit 120 of the air conditioner 100 is provided with an outdoor fan, a four-way valve, and the like, which are not shown, and the indoor unit 140 is provided with an indoor fan, which is not shown.
In the refrigeration cycle of the air conditioner 100, for example, the first heat exchanger 110 of the outdoor unit 120 operates as an evaporator. Conventionally, the refrigerant at the inlet of the heat exchanger functioning as an evaporator is in a gas-liquid two-phase state. In this gas-liquid two-phase state, it is extremely difficult to control the flow. Therefore, in the present embodiment, the gas-liquid separator 150 is provided in the refrigerant circuit, and only the refrigerant liquid is made to flow into the refrigerant tubes of the first heat exchanger 110, and measures against the refrigerant tubes of the microchannel heat exchanger of the first heat exchanger 110 are taken against the flow splitting failure.
In the air conditioner 100 of fig. 1, the compressor (compressor) 160 of the outdoor unit 120 is connected to the second heat exchanger 130 of the indoor unit 140. The second heat exchanger 130 operates as a condenser (condenser) during the heating operation to generate a refrigerant liquid. The second heat exchanger 130 is connected to the gas-liquid separator 150 via a first expansion valve 170. The gas-liquid separator 150 accumulates refrigerant liquid and refrigerant gas. The gas-liquid separator 150 that separates the two-phase gas-liquid refrigerant into the liquid refrigerant and the gas refrigerant is provided upstream of a first header described later.
When the refrigerant liquid in the gas-liquid separator 150 is sent to the first heat exchanger 110 and the first heat exchanger 110 operates as an evaporator, a refrigerant gas is generated. The first heat exchanger 110 is connected to the compressor 160. The refrigerant gas in the gas-liquid separator 150 is connected to the compressor 160 side of the first heat exchanger 110 via the second expansion valve 180, and forms a gas pressure regulating functional unit 190 (corresponding to a bypass passage in the present invention). That is, the flow rate and the flow pressure of the refrigerant gas sent from the first heat exchanger 110 to the compressor 160 can be adjusted by adjusting the pressure of the second expansion valve 180.
Next, an operation in the heating operation of the air conditioner 100 of fig. 1 will be described.
The refrigerant gas generated in the first heat exchanger 110 operating as an evaporator is supplied to the compressor 160 while being pressure-regulated by the gas pressure regulating function unit 190. The compressor 160 sends the refrigerant gas to the second heat exchanger 130 of the indoor unit 140. The second heat exchanger 130 operates as a condenser, and exchanges heat between the refrigerant gas and the air in the room to condense the refrigerant gas, thereby generating a refrigerant liquid and radiating heat to the room. The second heat exchanger 130 outputs the generated refrigerant liquid to the first expansion valve 170 of the outdoor unit 120.
The first expansion valve 170 performs pressure adjustment on the input refrigerant liquid as necessary, and sends the refrigerant liquid to the gas-liquid separator 150. Thus, even if the refrigerant liquid sent from the first expansion valve 170 contains refrigerant gas, the refrigerant liquid and the refrigerant gas are separated and accumulated in the gas-liquid separator 150 by being sent into the refrigerant liquid of the gas-liquid separator 150.
The refrigerant liquid in the gas-liquid separator 150 is then sent to the first heat exchanger 110, which operates as an evaporator. The first heat exchanger 110 is constituted by a microchannel heat exchanger described later. The first heat exchanger 110 exchanges heat between the refrigerant liquid and outdoor air to evaporate the refrigerant liquid, thereby generating a refrigerant gas. The refrigerant gas above the refrigerant liquid in the gas-liquid separator 150 is sent to the second expansion valve 180. By adjusting the pressure of the second expansion valve 180, the refrigerant gas sent from the first heat exchanger 110 to the compressor 160 is subjected to gas pressure adjustment, and only the refrigerant gas is supplied to the compressor 160, whereby the drift of the two-phase refrigerant can be suppressed. Accordingly, only the refrigerant gas can be supplied to the compressor 160, and thus only the refrigerant gas can be flowed into the refrigerant tube of the second heat exchanger 130.
Next, a countermeasure against the flow splitting failure in the first heat exchanger 110 will be described.
Fig. 2 is a diagram showing the configuration of the header portion and the refrigerant tubes of the microchannel heat exchanger 200 used in the first heat exchanger 110. In fig. 2, the first header 210 and the second header 220 are a common pipe that is common to a plurality of small-diameter refrigerant passages 230 described later. The first header 210 is divided into a lower portion (upstream portion) into which the refrigerant flows and an upper portion (downstream portion) into which the refrigerant flows by a partition wall (wall portion constituting an upper wall 280 described later) provided horizontally at a substantially center. On the other hand, the second header 220 communicates a lower portion (upstream portion) and an upper portion (downstream portion) via a second orifice 250 ″, which will be described later. The lower portion of the first header 210 and the lower portion of the second header 220 are connected by a plurality of small-diameter refrigerant channels 230(230a), and the upper portion of the first header 210 and the upper portion of the second header 220 are connected by a plurality of small-diameter refrigerant channels 230(230 b).
The small-diameter refrigerant flow paths 230 (corresponding to refrigerant tubes in the present invention) connecting the first header 210 and the second header 220 are formed by refrigerant tubes (flat tubes) in which a plurality of small-diameter tubes are arranged in the lateral direction. That is, the small-diameter refrigerant flow paths 230a and 230b are each constituted by a refrigerant tube (flat tube) having a microchannel formed therein. In the present embodiment, the 4 rows of small-diameter refrigerant channels 230 connecting the lower portion of the first header 210 and the lower portion of the second header 220 are referred to as small-diameter refrigerant channels 230a, and the 4 rows of small-diameter refrigerant channels 230 connecting the upper portion of the first header 210 and the upper portion of the second header 220 are referred to as small-diameter refrigerant channels 230 b. The refrigerant (refrigerant liquid) from the gas-liquid separator 150 flows through the lower portion of the first header 210, the small-diameter refrigerant passage 230a, the lower portion of the second header 220, the upper portion of the second header 220, the small-diameter refrigerant passage 230b, and the upper portion of the first header 210, and flows out to the compressor 160 side. The plurality of small-diameter refrigerant flow paths 230a and 230b are joined to the plurality of heat transfer fins 240, and heat exchange is performed between the refrigerant passing through the small-diameter refrigerant flow paths 230 and the air passing through the first heat exchanger 110 (that is, the refrigerant can absorb heat from the air).
Here, in the embodiment, as a countermeasure against the flow dividing failure, the orifices 250 are provided in the first header 210 and the second header 220, respectively. Specifically, the orifice 250 is formed by a hole that opens to a partition wall provided in the first header 210 and the second header 220. The refrigerant liquid accelerated by the orifice 250 collides with the upper walls 280 and 290 of the headers to swirl. This prevents the refrigerant liquid from separating due to gravity and prevents a flow splitting failure. In fig. 2, the orifice in the first header 210 on the inflow side (upstream side) is referred to as a first orifice 250 ', and the orifice in the second header 220 on the downstream side of the first orifice 250' is referred to as a second orifice 250 ″.
The first orifice 250' is provided upstream (i.e., vertically below) of the plurality of small-diameter refrigerant flow paths (refrigerant tubes) 230a connected to the downstream side of the first header 210. More specifically, the first orifice 250' is provided between the inlet 260 through which the refrigerant flows into the first header 210 and the opening of the small-diameter refrigerant passage (refrigerant tube) 230a on the side of the first header 210. In the present embodiment, the first orifice 250' is provided in the vicinity of the upper side of the inflow port 260 that opens in the horizontal direction (the direction perpendicular to the first header 210) on the lower side of the first header 210. The second orifice 250 ″ is disposed upstream of the plurality of small-diameter refrigerant flow paths (refrigerant tubes) 230b connected to the downstream side of the second header 220. More specifically, the second orifice 250 ″ is provided between the opening of the small-diameter refrigerant flow passage (refrigerant tube) 230a on the second header 220 side and the opening of the small-diameter refrigerant flow passage (refrigerant tube) 230b on the second header 220 side. In the present embodiment, the second orifice 250 ″ is provided in the folded-back intermediate portion of the second header 220 in the horizontal direction (the direction perpendicular to the second header 220). The folded middle portion is a position between the uppermost position of the lower 4 rows of the small-diameter refrigerant passages 230a and the lowermost position of the upper 4 rows of the small-diameter refrigerant passages 230 b.
Fig. 3 shows an example of the first throttle hole 250' and the second throttle hole 250 ″. For example, in fig. 3(a), a plurality of circular holes 250a are provided in the orifice 250 (both orifices are shown). In fig. 3(b), the orifice 250 is provided with a plurality of rectangular holes 250 b. In fig. 3(c), of the plurality of circular holes of the orifice hole 250, the center hole 250c1 is formed larger than the outer holes 250c 2. In fig. 3(d), a plurality of rectangular holes 250d smaller than those in fig. 3(b) are provided. In this manner, the size, shape, number, and the like of the holes of the orifice 250 may be optimally designed according to the size of the orifice itself, the pressure at the time of inflow of the refrigerant liquid, and the like.
Returning to fig. 2, in the present embodiment, meshes 270 are provided in the inlet 260 of the first header 210. By providing the mesh 270, turbulence can be generated in the refrigerant liquid. The refrigerant liquid flowing in through mesh 270 is accelerated in speed by first orifice 250' in first header 210 in the vicinity of inflow port 260, and collides with upper wall 280 due to its momentum. This can cause the refrigerant liquid that has been disturbed in the first header 210 to swirl. The refrigerant liquid is easily distributed equally to the four small-diameter refrigerant flow paths 230a by the swirl generated in the first header 210. In the small-diameter refrigerant flow path 230a, the refrigerant liquid exchanges heat with outdoor air and evaporates, and a refrigerant gas is generated. At this stage, the refrigerant liquid is not completely gasified, and therefore a part of the remaining refrigerant liquid and the generated refrigerant gas are sent to the second header 220.
In the second header 220, the refrigerant liquid is also accelerated by the second orifice 250 "and collides with the upper wall 290. This can swirl the refrigerant liquid in the second header 220. The refrigerant liquid is easily distributed uniformly to the four small-diameter refrigerant flow paths 230b by the swirl generated in the second header 220, and then the refrigerant liquid passes through the small-diameter refrigerant flow paths 230b and turns back toward the first header 210. In the small-diameter refrigerant flow path 230b, the refrigerant liquid that is not gasified by the heat exchange in the small-diameter refrigerant flow path 230a is evaporated by the heat exchange with the outdoor air, and the refrigerant liquid is gasified to generate the refrigerant gas. The generated refrigerant gas is supplied from the outlet 295 provided on the upper side of the upper wall 280 of the first header 210 toward the compressor 160 (see fig. 1).
Therefore, in the embodiment, the refrigerant liquid is turbulent by the mesh 270, and the refrigerant liquid accelerated by the first and second orifices 250' and 250 ″ provided in the first and second headers 210 and 220 collides with the upper walls 280 and 290 to be swirled. This makes it possible to easily and equally distribute the refrigerant liquid in the upstream-side plurality of small-diameter refrigerant flow paths 230a and the downstream-side plurality of small-diameter refrigerant flow paths 230 b. Note that, in the first header 210, if the coolant can be distributed substantially equally only by the first orifice 250' on the upstream side, the mesh 270 may not be provided.
Fig. 4 is a diagram showing another embodiment of the air conditioner.
In the present embodiment, the flow rate of the refrigerant flowing through each of the small-diameter refrigerant flow paths can be further reduced, and the pressure loss can be further suppressed. Specifically, in the air conditioner shown in fig. 4, the microchannel heat exchanger is divided into two blocks, and the amount of refrigerant flowing through the small-diameter refrigerant flow path of each block is reduced, thereby suppressing the pressure loss.
The microchannel heat exchanger 300 of the air conditioner shown in fig. 4 is divided into a first block 310 and a second block 320. The basic configuration of each block 310, 320 is the same as that shown in fig. 2. That is, in the present embodiment, the first header 410 and the second header 420 are divided into the flow path blocks corresponding to the blocks 310 and 320, respectively. Specifically, the first header 410 is divided into a lower block constituting a lower half portion and an upper block constituting an upper half portion, and the lower block and the upper block of the first header 410 are divided into a lower portion into which the refrigerant flows and an upper portion into which the refrigerant flows out, respectively. The second header 420 is divided into a lower block constituting the lower half and an upper block constituting the upper half, and the lower block and the upper block of the second header 420 are divided into a lower portion and an upper portion, respectively, through which the refrigerant communicates via the orifice.
The inflow ports 315 and 325 are connected to the lower portion of the upper block of the first header 410 constituting the first block 310 and the lower portion of the lower block of the first header 410 constituting the second block 320, respectively. Further, meshes are provided inside the inlets 315 and 325. The inlets 315 and 325 are connected to the flow divider 330 via refrigerant pipes. Thus, the refrigerant (refrigerant liquid) is split into two flows by the flow splitter 330, and is sent to the first block 310 and the second block 320, respectively, while being turbulent by the mesh openings. Further, a common outlet port 340 is connected to an upper portion of an upper block of the first header 410 constituting the first block 310 and an upper portion of a lower block of the first header 410 constituting the second block 320. The common outlet 340 is configured such that an outlet portion connected to the first block 310 and an outlet portion connected to the second block 320 join in the middle. Further, the flow paths from the lower portion of the lower block of the first header 410 to the common flow outlet 340 via the plurality of small-diameter refrigerant flow paths 230, the lower block of the second header 420, and the upper portion of the lower block of the first header 410, and the flow paths from the lower portion of the upper block of the first header 410 to the common flow outlet 340 via the plurality of small-diameter refrigerant flow paths 230, the upper block of the second header 420, and the upper portion of the upper block of the first header 410 correspond to the branch flow paths in the present invention, respectively.
In the microchannel heat exchanger 300 configured as described above, the flow dividing process and the heat exchange operation described in the first embodiment are performed in the first block 310 and the second block 320. That is, in the flow dividing process, as shown in fig. 4, the refrigerant liquid accelerated by the orifices 360 ', 360 ", 370', 370" provided in the headers 410, 420 is caused to collide with the upper wall to swirl, whereby the refrigerant liquid can be equally distributed into the small-diameter refrigerant flow paths. The first block 310 and the second block 320 gasify the refrigerant liquid flowing in to generate only the refrigerant gas, and supply the generated refrigerant gas to the compressor 160 from the common outlet 340. Therefore, according to the air conditioner of the present embodiment, the microchannel heat exchanger is divided into two blocks, and the amount of refrigerant flowing through the small-diameter refrigerant passage of each block is reduced, whereby the pressure loss can be reduced. The orifices 360 ', 360 ", 370', 370" are provided in the respective blocks of the first header 410 and the second header 420, but are not limited thereto. That is, an orifice for increasing the flow rate of the refrigerant flowing through the inside may be provided in at least one block of at least one of the first header 410 and the second header 420.
In the embodiment, the microchannel heat exchanger 200 is described as an example of the configuration of the first heat exchanger 110 in fig. 1, but the same configuration may be implemented in the second heat exchanger 130 that operates as an evaporator during the cooling operation. The refrigerant gas generated by the second heat exchanger 130 during the cooling operation is sent to the compressor 160 via a four-way valve not shown. In the cooling operation, the first heat exchanger 110 operates as a condenser. Therefore, both the first heat exchanger 110 and the second heat exchanger 130 may be configured by the microchannel heat exchanger described in the embodiment. Further, the refrigerant gas sent from the common outlet 340 in fig. 4 may be supplied to the compressor 160 by performing gas pressure adjustment of 0 using the gas pressure adjustment functional unit 19 in fig. 1.
As described above, the microchannel heat exchanger 200 according to the first embodiment includes: in the microchannel heat exchanger 200, the first header 210 constituting the flow path on the upstream side, the second header 220 into which the refrigerant from the first header 210 is introduced, the plurality of small-diameter refrigerant flow paths 230 connecting the first header 210 and the second header 220, and the heat transfer fins 240 joined to the plurality of small-diameter refrigerant flow paths 230, at least one of the first header 210 and the second header 220 is configured such that the orifice 250 for increasing the flow velocity of the refrigerant flowing through the inside is provided upstream of the plurality of small-diameter refrigerant flow paths 230 connected to the downstream side of the header, and therefore, the refrigerant liquid can collide with the header upper wall and swirl can be generated by the orifice 250 provided in the header. This prevents the refrigerant liquid from being biased downward by gravity or prevents a flow splitting failure from occurring. In addition, the refrigerant liquid in the header can be easily distributed equally to the plurality of refrigerant tubes. As a result, the occurrence of evaporation to dryness can be suppressed. Further, since the orifice 250 is provided in the first header 210 or the second header 220, the flow path in the header does not need to be formed into a complicated shape, and the processing is easy. As a result, the manufacturing cost can be reduced.
Further, since the mesh 270 is provided upstream of the first orifice 250', the refrigerant liquid flowing into the first header 210 can be turbulent by the mesh 270. This makes it possible to further evenly distribute the refrigerant liquid in the first header 210 to the plurality of small-diameter refrigerant flow paths 230. Further, the mesh may be provided directly before the second orifice 250 ", that is, between the second orifice 250" and the openings of the plurality of small-diameter refrigerant flow paths 230 on the upstream side.
Further, since the inflow port 260 connected to the first header 210 and through which the refrigerant passes toward the first header 210 is provided and the mesh 270 is provided in the inflow port 260, turbulence can be generated in the refrigerant liquid flowing into the first header 210. This makes it possible to further evenly distribute the refrigerant liquid in the first header 210 to the plurality of small-diameter refrigerant flow paths 230. In addition, the mesh is easier to install than a configuration in which the mesh is provided in the first header 210.
Further, since the second header 220 is configured such that the second orifice 250 ″ is provided between the connection position of the plurality of small-diameter refrigerant flow paths 230 on the upstream side and the connection position of the plurality of small-diameter refrigerant flow paths 230 on the downstream side, the refrigerant liquid can collide with the upper wall in the second header 220 and swirl is generated in the second header 220 by the second orifice 250 ″. This prevents the refrigerant liquid from being biased downward by gravity in the second header 220, thereby preventing a flow splitting failure from occurring. Therefore, the refrigerant liquid in the second header 220 can be easily distributed equally to the plurality of small-diameter refrigerant flow paths 230.
Further, the gas-liquid separator 150 for separating the two-phase gas-liquid refrigerant into the liquid refrigerant and the gas refrigerant is provided upstream of the first header 210, and the liquid refrigerant from the gas-liquid separator 150 can be introduced into the first header 210, so that only the refrigerant liquid is supplied to the first header 210. This makes it easier to equally distribute the refrigerant to the plurality of small-diameter refrigerant channels 230. Further, with the gas-liquid separator 150, only the refrigerant gas can be made to flow into the compressor 160, and it is easy to make only the refrigerant gas flow into the first heat exchanger 130.
Further, since the gas pressure regulating function unit 190 is provided so as to bypass the first header and the second header, and the gas pressure of the compressor is regulated by the gas pressure regulating function unit 190, the pressure of the refrigerant gas sent to the compressor can be adjusted by adjusting the pressure of the gas pressure regulating function unit 190. This can reduce the workload of the compressor 160.
In the other embodiment shown in fig. 4, the first header 410 and the second header 420 are each divided into a plurality of blocks by partition walls, a plurality of flow dividing paths each composed of at least the block of the first header 410, the block of the second header 420, and the plurality of small-diameter refrigerant flow paths 230 are formed, and a flow divider 330 for dividing the refrigerant into the flow dividing paths is provided, and at least one block of at least one of the first header 410 and the second header 420 is configured such that an orifice for increasing the flow rate of the refrigerant flowing therethrough is provided upstream of the plurality of small-diameter refrigerant flow paths 230 connected to the downstream side of the block. Further, by causing the refrigerant liquid to collide with the header upper wall by the orifices provided in the headers of the respective blocks to generate a swirl, the refrigerant liquid can be prevented from being biased downward, and a flow dividing failure can be prevented from occurring. This makes it easy to equally distribute the refrigerant liquid in the header of each block to the plurality of small-diameter refrigerant channels 230.
Further, the inlets 315 and 325 are configured such that a plurality of inlets 315 and 325 are provided for each block on the upstream side of the first header 410 (i.e., the lower portion of the upper block of the first header 410 and the lower portion of the lower block of the first header 410), and a mesh is provided for each of the inlets 315 and 325, so that turbulence can be generated in the refrigerant liquid flowing into each block of the first header 410 by the mesh. This makes it easy to distribute the refrigerant liquid from each block in the first header 410 to the plurality of small-diameter refrigerant channels 230 more uniformly.
Since the microchannel heat exchanger as described above is mounted on the outdoor unit 120 of the air conditioner 100, the air conditioner 100 can suppress a flow distribution failure in the first heat exchanger 110 of the outdoor unit 120.
Further, if the microchannel heat exchanger as described above is mounted on the indoor unit 140 of the air conditioner 100, the air conditioner 100 can be provided in which a flow-splitting failure in the second heat exchanger 130 of the indoor unit 140 can be suppressed.
The embodiments of the present invention are provided as examples, and are not intended to limit the scope of the invention. These new embodiments can be implemented in other various ways, and various omissions, substitutions, and changes can be made without departing from the spirit and scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalent scope thereof.
Claims (10)
1. A microchannel heat exchanger including a first header constituting an upstream-side flow path, a second header into which a refrigerant is introduced from the first header, a plurality of refrigerant tubes connecting between the first header and the second header, and heat transfer fins joined to the plurality of refrigerant tubes,
in at least one of the first header and the second header, an orifice for increasing the flow rate of the refrigerant flowing through the interior is provided upstream of the plurality of refrigerant tubes connected to the downstream side of the header.
2. The microchannel heat exchanger of claim 1,
a mesh is provided upstream of the orifice.
3. The microchannel heat exchanger of claim 2,
an inflow port connected to the first header and through which the refrigerant passes toward the first header,
the mesh is provided at the inflow port.
4. The microchannel heat exchanger of any one of claims 1 to 3,
in the second header, the orifice is provided between a connection position of the plurality of refrigerant tubes on an upstream side and a connection position of the plurality of refrigerant tubes on a downstream side.
5. The microchannel heat exchanger of any one of claims 1 to 4,
a gas-liquid separator for separating a gas-liquid two-phase refrigerant into a liquid refrigerant and a gas refrigerant is provided upstream of the first header,
liquid refrigerant from the gas-liquid separator can be introduced into the first header.
6. The microchannel heat exchanger of claim 5,
a bypass passage connected to the gas-liquid separator and bypassing the first header and the second header,
the bypass flow path is used to regulate the pressure of the gas in the compressor.
7. The microchannel heat exchanger of any one of claims 1 to 6,
the first header and the second header are divided into a plurality of blocks by partition walls,
a plurality of branch paths formed at least by the block of the first header, the block of the second header, and the plurality of refrigerant tubes are formed,
the microchannel heat exchanger is provided with a flow divider for dividing the refrigerant into flow paths,
in at least one block of the header of at least one of the first header and the second header, an orifice for increasing the flow rate of the refrigerant flowing through the block is provided upstream of the plurality of refrigerant tubes connected to the downstream side of the block.
8. The microchannel heat exchanger of claim 7,
a plurality of the inflow ports are provided in each block on the upstream side of the first header,
the meshes are provided at each inflow port.
9. An air conditioner is characterized in that,
the outdoor unit of the air conditioner, wherein the microchannel heat exchanger according to any one of claims 1 to 8 is mounted on the outdoor unit.
10. An air conditioner is characterized in that,
the microchannel heat exchanger according to any one of claims 1 to 8 is mounted on an indoor unit of the air conditioner.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2020-016629 | 2020-02-03 | ||
| JP2020016629A JP7470909B2 (en) | 2020-02-03 | 2020-02-03 | Microchannel heat exchanger and air conditioner |
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| CN113217996A true CN113217996A (en) | 2021-08-06 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202011445830.7A Pending CN113217996A (en) | 2020-02-03 | 2020-12-09 | Microchannel heat exchanger and air conditioner |
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| JP (1) | JP7470909B2 (en) |
| CN (1) | CN113217996A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116147233A (en) * | 2023-04-21 | 2023-05-23 | 广东美博智能环境设备有限公司 | Efficient refrigeration plant heat exchange tube |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114264092A (en) * | 2022-01-04 | 2022-04-01 | 珠海格力电器股份有限公司 | Refrigerant circulation equipment and system, control method, controller and storage medium |
| JP7392757B2 (en) * | 2022-03-30 | 2023-12-06 | 株式会社富士通ゼネラル | Air conditioner indoor unit |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH03140764A (en) * | 1989-10-26 | 1991-06-14 | Nippondenso Co Ltd | Heat exchanger |
| JP2004233014A (en) * | 2003-01-31 | 2004-08-19 | Toyo Radiator Co Ltd | Heat exchanger, and method for manufacturing flat tube and header thereof |
| US20090183857A1 (en) * | 2007-10-19 | 2009-07-23 | David Bland Pierce | Turbulator for a heat exchanger tube, and method of manufacture |
| CN102519181A (en) * | 2011-12-09 | 2012-06-27 | 广东美的电器股份有限公司 | Parallel flow heat exchanger |
| CN103620336A (en) * | 2011-07-05 | 2014-03-05 | 夏普株式会社 | Heat exchanger and air conditioner equipped with same |
| CN104272040A (en) * | 2012-04-26 | 2015-01-07 | 三菱电机株式会社 | Coolant distributor, and heat exchanger equipped with coolant distributor |
| JP2016095094A (en) * | 2014-11-14 | 2016-05-26 | 東芝キヤリア株式会社 | Heat exchanger and refrigeration cycle device |
| JP2018194251A (en) * | 2017-05-19 | 2018-12-06 | 株式会社富士通ゼネラル | Heat exchanger |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000304378A (en) * | 1999-04-23 | 2000-11-02 | Mitsubishi Heavy Ind Ltd | Condenser, refrigerant system and air conditioner for vehicle |
| FR2988825B1 (en) | 2012-03-30 | 2015-05-01 | Valeo Systemes Thermiques | THERMAL EXCHANGER, IN PARTICULAR FOR VEHICLE |
| WO2016121123A1 (en) * | 2015-01-30 | 2016-08-04 | 三菱電機株式会社 | Refrigeration cycle device |
| JP6544294B2 (en) * | 2016-05-10 | 2019-07-17 | 株式会社デンソー | Heat exchanger |
-
2020
- 2020-02-03 JP JP2020016629A patent/JP7470909B2/en active Active
- 2020-12-09 CN CN202011445830.7A patent/CN113217996A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH03140764A (en) * | 1989-10-26 | 1991-06-14 | Nippondenso Co Ltd | Heat exchanger |
| JP2004233014A (en) * | 2003-01-31 | 2004-08-19 | Toyo Radiator Co Ltd | Heat exchanger, and method for manufacturing flat tube and header thereof |
| US20090183857A1 (en) * | 2007-10-19 | 2009-07-23 | David Bland Pierce | Turbulator for a heat exchanger tube, and method of manufacture |
| CN103620336A (en) * | 2011-07-05 | 2014-03-05 | 夏普株式会社 | Heat exchanger and air conditioner equipped with same |
| CN102519181A (en) * | 2011-12-09 | 2012-06-27 | 广东美的电器股份有限公司 | Parallel flow heat exchanger |
| CN104272040A (en) * | 2012-04-26 | 2015-01-07 | 三菱电机株式会社 | Coolant distributor, and heat exchanger equipped with coolant distributor |
| JP2016095094A (en) * | 2014-11-14 | 2016-05-26 | 東芝キヤリア株式会社 | Heat exchanger and refrigeration cycle device |
| JP2018194251A (en) * | 2017-05-19 | 2018-12-06 | 株式会社富士通ゼネラル | Heat exchanger |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116147233A (en) * | 2023-04-21 | 2023-05-23 | 广东美博智能环境设备有限公司 | Efficient refrigeration plant heat exchange tube |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2021124226A (en) | 2021-08-30 |
| JP7470909B2 (en) | 2024-04-19 |
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