CN114440328A

CN114440328A - Heat exchanger and refrigeration cycle device provided with same

Info

Publication number: CN114440328A
Application number: CN202210159443.XA
Authority: CN
Inventors: 田代雄亮
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2014-05-15
Filing date: 2014-05-15
Publication date: 2022-05-06
Also published as: EP3144624A1; US20170074564A1; JP5864030B1; EP3144624A4; JPWO2015173938A1; WO2015173938A1; CN106461350A

Abstract

The invention provides a heat exchanger and a refrigeration cycle device with the same. The fin (1) is provided with a region (L) where the heat transfer promoting portion (3) is not provided and a region other than the region (L) where the heat transfer promoting portion (3) is provided, and the region (L) is a region between the lower end portion of the heat transfer tube (2A) and the upper end portion of the heat transfer tube (2B).

Description

Heat exchanger and refrigeration cycle device provided with same

The present application is a divisional application entitled "heat exchanger and refrigeration cycle device including the same", having an application date of 5/15/2014 and an application number of "201480078695.3".

Technical Field

The present invention relates to a heat exchanger provided in a heat source device such as an outdoor unit while suppressing deterioration of frost resistance, and a refrigeration cycle including the heat exchanger.

Background

Conventionally, fin-tube type heat exchangers are used as heat exchangers for refrigeration cycle apparatuses such as air conditioners. Such a heat exchanger is generally configured by inserting a plurality of heat transfer tubes having a circular cross section into a plurality of plate-like fins having circular holes formed therein.

As such a configuration, there has been proposed "a fin-and-tube heat exchanger including a plurality of heat transfer fins stacked substantially in parallel with a predetermined interval and a plurality of heat transfer tubes penetrating the heat transfer fins in a direction substantially orthogonal to a planar direction of the heat transfer fins, wherein a substantially cylindrical fin washer extending in a direction substantially orthogonal to the planar direction of the heat transfer fins is formed around a through hole of the heat transfer fin through which the heat transfer tube penetrates, the heat transfer tube is inserted into the through hole in a state of being in close contact with the fin washer, and heat exchange is performed between a gas flowing in the planar direction of the heat transfer fins and a cold-hot medium flowing inside the heat transfer tube, wherein the heat transfer fins are provided with cutouts only in a layer direction that is a direction substantially orthogonal to a flow direction of the gas, and the fin-and-tube heat exchanger includes a ridge portion, the peak portion bulges the heat transfer fin portion on the windward side of the slit where the gas flows, has an opening portion formed by the slit on the leeward side, and is not formed at a position intersecting a straight line passing through the center of the heat transfer pipe and parallel to the flow direction of the gas (see, for example, patent document 1).

Further, it is proposed "a heat exchanger comprising:

heat transfer tubes

12, 12 …, 12 …; a plurality of electric heating fins 13a, 13a …, 13b … arranged in parallel to the

heat transfer tubes

12, 12 …, 12 … in a crossing state; and cut-and-raised

pieces

14, 14 …, 14 … provided on the electric heating surfaces of the electric heating fins 13a, 13a …, 13b …, wherein linear portions b, b …, c … for guiding condensed water extending downward are provided at the lower end portions of the cut-and-raised

pieces

14, 14 …, 14 … (see, for example, patent document 2).

Further, "a heat exchanger including a heat transfer tube, a plurality of electric heating fins arranged in parallel in a state of intersecting the heat transfer tube, and a cut-and-raised piece provided on an electric heating surface of the electric heating fins, wherein a water guide portion for drainage is provided at a lower end portion of the cut-and-raised piece has been proposed (for example, see patent document 3).

Prior art documents

Patent document

Patent document 1: japanese patent No. 4775429 (embodiment 1, etc.)

Patent document 2: japanese patent laid-open No. 2008-249320 (FIGS. 1 and 2, etc.)

Patent document 3: japanese patent laid-open No. 2010-255974 (FIGS. 1 and 2, etc.)

Disclosure of Invention

Problems to be solved by the invention

In the fin-tube type heat exchanger described in patent document 1, the formation of the ridge portion enables excellent heat transfer performance to be obtained, and the range where the ridge portion is not formed is determined to secure a drainage path for condensed water, thereby suppressing an increase in ventilation resistance.

The heat exchangers described in

patent documents

2 and 3 have slits or the like between the heat transfer pipes to improve heat transfer and improve performance of the heat exchanger, and have been made to provide drainage paths or the like between the heat transfer pipes to improve drainage.

When the heat exchanger configured as described above is installed in a heat source device such as an outdoor unit to perform a heating operation, the heat exchanger functions as an evaporator. When the heat exchanger is used as an evaporator, frost formation may occur in the heat exchanger. Frost formed in the heat exchanger occurs from the heat transfer tube portion in addition to the fin leading edge portion (the most upstream side of the air flow of the fin) and the fin slit portion. Frost formed in the heat transfer pipe portion may cause air passage blockage.

In the heat exchanger described in any of patent documents 1 to 3, since the heat transfer tubes that become the air escape paths during frost formation have ridges or notches therebetween, heat transfer can be promoted, and the air escape paths are blocked by the growing frost during frost formation.

In particular, when frost formation occurs in the heat transfer pipe portion located on the upstream side of the air passage, frost resistance deteriorates, air cannot reach the downstream side of the heat exchanger, and heat exchange is not performed during the frost formation, that is, frost resistance is low.

The present invention has been made to solve the above-described problems, and an object thereof is to provide a heat exchanger that ensures an escape path of air during frosting and suppresses a decrease in frost resistance, and a refrigeration cycle apparatus including the heat exchanger.

Means for solving the problems

A heat exchanger according to the present invention is a heat exchanger including a plurality of fins arranged in parallel at predetermined intervals and a heat transfer pipe penetrating the plurality of fins, the plurality of fins having a multi-row structure, the heat transfer pipe being arranged in a plurality of rows in a direction orthogonal to a row direction of the plurality of fins, the heat transfer pipe including: a first heat transfer pipe that penetrates the fins of the first row when viewed from the most upstream side of the air flow flowing through the heat exchanger; and a second heat transfer tube which penetrates the fins of the second row, is closest to the first heat transfer tube, and is located above and below the first heat transfer tube in the layer direction, wherein the fins of the first row and the fins of the second row arranged in the row direction are provided with a first region and a second region, the first region is at least partially provided with a slit, the second region is not provided with the slit, the second region is provided in at least one of a region between a lower end portion of the first heat transfer tube and an upper end portion of the second heat transfer tube and a region between an upper end portion of the first heat transfer tube and a lower end portion of the second heat transfer tube, the second region is continuous in the row direction on the fins of the first row and the fins of the second row, and extends from an upwind direction of the fins of the first row to a plane portion in a downwind direction of the fins of the second row in the air flow direction, the width of the second region in the layer direction is larger than the width of the first region in the layer direction.

The refrigeration cycle device of the present invention includes: a heat source unit on which the heat exchanger is mounted; and a utilization-side device connected to the heat source unit.

Effects of the invention

According to the heat exchanger of the present invention, since the second region is provided in the fin, an escape path of air during frost formation can be secured, and a decrease in frost resistance can be suppressed.

According to the refrigeration cycle apparatus of the present invention, since the heat exchanger is provided, even when the heat exchanger is frosted, the air passage of the heat exchanger is not blocked, and the operation can be continuously performed.

Drawings

Fig. 1 is a perspective view schematically showing an internal structure of a heat source unit provided with an example of a heat exchanger according to embodiment 1 of the present invention.

Fig. 2 is an explanatory diagram for explaining a configuration of a heat source unit provided with an example of the heat exchanger according to embodiment 1 of the present invention.

Fig. 3 is a schematic view schematically showing an example of the heat exchanger according to embodiment 1 of the present invention, as viewed from the central axis direction side of the heat transfer tubes.

Fig. 4 is a schematic view schematically showing another example of the heat exchanger according to embodiment 1 of the present invention, as viewed from the central axis direction side of the heat transfer tubes.

Fig. 5 is a schematic view schematically showing another example of the heat exchanger according to embodiment 1 of the present invention, as viewed from the central axis direction side of the heat transfer tubes.

Fig. 6 is a schematic view schematically showing a heat exchanger according to embodiment 1 of the present invention, as viewed from a direction orthogonal to the central axis direction of the heat transfer tubes.

Fig. 7 is a schematic explanatory view for explaining an example of specific numerical values of the heat exchanger according to embodiment 1 of the present invention.

Fig. 8 is a refrigerant circuit diagram schematically showing a basic refrigerant circuit configuration of a refrigeration cycle apparatus according to embodiment 2 of the present invention.

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to the drawings as appropriate. In the following drawings including fig. 1, the size relationship of each component may be different from the actual one. In the following drawings including fig. 1, the same or equivalent members are denoted by the same reference numerals and are used in common throughout the specification. Note that the modes of constituting components shown throughout the specification are merely examples, and are not limited to these descriptions.

Embodiment 1.

Fig. 1 is a perspective view schematically showing an internal configuration of a heat source unit 60 provided with an example of a heat exchanger (hereinafter, referred to as a heat exchanger 50) according to embodiment 1 of the present invention. Fig. 2 is an explanatory diagram for explaining the structure of the heat source unit 60. First, the structure of the heat source unit 60 will be described with reference to fig. 1 and 2.

The heat source unit (also referred to as an outdoor unit or an outdoor unit) 60 constitutes a part of the refrigeration cycle apparatus. The heat source unit 60 is connected to an indoor unit (also referred to as an indoor unit, a user-side device (user-side unit), or a load-side device (load-side unit)) to constitute a refrigeration cycle apparatus. The unit devices (the compressor, the heat source-side heat exchanger (heat exchanger 50), the expansion device (expansion valve 12), and the use-side heat exchanger 71) mounted on the heat source unit 60 and the indoor unit are connected by pipes to form a refrigerant circuit, and thereby, for example, an air conditioning operation and a hot water supply operation are performed. The refrigeration cycle apparatus is described in embodiment 2.

The heat source unit 60 includes a frame 60A constituting an outline. As shown in fig. 1 and 2, a partition plate 61 is provided inside the housing 60A. By providing the partition plate 61, the inside of the housing 60A is divided into a machine chamber 62 and a blower chamber 63.

The machine chamber 62 is provided with a compressor 10, a four-way valve 11, an expansion valve 12, a muffler 16, a refrigerant pipe 15 connecting these components, and the like.

The blower chamber 63 is provided with the heat exchanger 50, the blower fan 20, the fan motor 21, the motor support 22, and the like.

The details of the respective members provided in the machine chamber 62 and the blower chamber 63 will be described below.

The compressor 10 compresses a refrigerant circulating through a refrigeration cycle into a high-temperature and high-pressure refrigerant, and discharges the refrigerant.

The four-way valve 11 is a member that switches the flow of the refrigerant in accordance with the operation. When a hot-air supply operation for supplying hot air to the load side is performed, the four-way valve 11 is switched as shown by a solid line in fig. 2. When the cooling energy supply operation for supplying cooling energy to the load side is performed, switching is performed as shown by the broken line in fig. 2.

The expansion valve 12 decompresses and expands the refrigerant, and is configured to be capable of variably controlling the opening degree, for example, an electronic expansion valve or the like.

The muffler 16 serves to stabilize the flow rate of the refrigerant by accumulating a predetermined amount of the gas refrigerant and flowing the refrigerant to the compressor 10.

The heat exchanger 50 is a cross-fin-tube type heat exchanger. Details regarding the heat exchanger 50 are described later. The heat exchanger 50 is formed in a substantially L-shape in a plan view. By forming the heat exchanger 50 in a substantially L-shape, the heat exchange area of the heat exchanger 50 can be increased.

The air blowing fan 20 is an air blowing mechanism constituted by an axial flow fan (propeller fan), for example.

The fan motor 21 is used to rotate the blower fan 20. The fan motor 21 is supported by a motor support 22.

The motor support 22 is a member that supports the fan motor 21.

The operation of the heat source unit 60 during the heating energy supply operation will be described.

When the compressor 10 is driven, the refrigerant is pressurized by the compressor 10, and discharged in a high-temperature and high-pressure state. The refrigerant discharged from the compressor 10 passes through the four-way valve 11, is supplied to a heat exchanger mounted in an indoor unit, not shown, and is cooled by heat exchange with air, thereby reaching a low-temperature and high-pressure state. At this time, air for heating is supplied from the indoor unit, and the space to be air-conditioned is heated. The refrigerant returns to the heat source unit 60, and is expanded and decompressed by the expansion valve 12 into a low-temperature and low-pressure state. The refrigerant is heated by the heat exchanger 50 and then returns to the compressor 10 again.

When the refrigeration cycle apparatus performs a heating energy supply operation (for example, a heating operation), the heat exchanger 50 functions as an evaporator in the heat source unit 60. When the heat exchanger 50 is caused to function as an evaporator, frost formation may occur in the heat exchanger 50. As described above, frost formed in the heat exchanger 50 is generated from the heat transfer tube portion in addition to the fin leading edge portion and the fin slit portion. When frost grows, any air passage is closed.

In general, in a cross-fin-tube type heat exchanger, a heat transfer promoting portion such as a slit is formed in a fin in order to exhibit a heat transfer promoting effect. When such a heat transfer promoting portion is present, heat transfer can be promoted, and even an escape path of air to be secured at the time of frost formation is blocked by frost. In particular, when frost forms on the heat transfer pipe portion located on the upstream side of the air passage, air cannot reach the downstream side of the heat exchanger, and heat exchange cannot be performed during the frost formation. That is, the frost resistance of the heat exchanger is significantly reduced. Therefore, the heat exchanger 50 has the following structure.

Fig. 3 is a schematic view schematically showing an example of the heat exchanger 50 as viewed from the central axis direction side of the heat transfer tubes. Fig. 4 is a schematic view schematically showing another example of the heat exchanger 40 as viewed from the central axis direction side of the heat transfer pipe. Fig. 5 is a schematic view schematically showing another example of the heat exchanger 50, as viewed from the central axis direction side of the heat transfer tubes. Fig. 6 is a schematic view schematically showing a state of the heat exchanger 50 viewed from a direction orthogonal to the central axis direction of the heat transfer tubes. Fig. 7 is a schematic explanatory diagram for explaining an example of specific numerical values of the heat exchanger 50. The heat exchanger 50 will be described in detail with reference to fig. 3 to 7. Fig. 3 and 4 illustrate a heat exchanger 50 having a 2-row structure as an example, and fig. 5 illustrates a heat exchanger 50 having a 3-row structure as an example.

As shown in fig. 5, the heat exchanger 50 includes a plurality of fins 1 arranged in parallel with each other at predetermined intervals, and a heat transfer tube 2 penetrating the plurality of fins 1, and performs heat exchange between air flowing between the fins 1 and refrigerant flowing inside the heat transfer tube 2.

The fins 1 are arranged in a plurality of rows in a direction parallel to the air flow direction.

In fig. 3, the fin 1 disposed on the upstream side of the air flow is illustrated as a fin 1A, and the fin 1 disposed on the downstream side of the air flow is illustrated as a fin 1B. That is, in the example shown in fig. 3, the fins 1 have a 2-row structure.

In fig. 5, the fin 1 disposed on the upstream side of the air flow is illustrated as a fin 1A, the fin 1 disposed on the downstream side of the air flow is illustrated as a fin 1C, and the fin 1 disposed between the fin 1A and the fin 1C is illustrated as a fin 1B. That is, in the example shown in fig. 5, the fins 1 have a 3-row structure.

The direction parallel to the air flow direction is defined as the "column direction".

The fins 1A correspond to "fins in the first row" when viewed from the most upstream side of the air flow flowing through the heat exchanger 50.

The fins 1B correspond to "fins in the second row" when viewed from the most upstream side of the air flow flowing through the heat exchanger 50.

The heat transfer tubes 2 are provided in plural in a direction perpendicular to the flow direction of the air in the fins 1.

In fig. 3, the heat transfer tubes 2 penetrating the fins 1A are illustrated as heat transfer tubes 2A, and the heat transfer tubes 2 penetrating the fins 1B are illustrated as heat transfer tubes 2B. That is, in the example shown in fig. 3, the heat transfer pipe 2 is arranged in a plurality of layers. That is, the heat transfer tubes 2 are arranged in a plurality of layers in the direction orthogonal to the row direction of the fins 1.

In fig. 5, the heat transfer tubes 2 penetrating the fins 1A are illustrated as heat transfer tubes 2A, the heat transfer tubes 2 penetrating the fins 1B are illustrated as heat transfer tubes 2B, and the heat transfer tubes 2 penetrating the fins 1C are illustrated as heat transfer tubes 2C. That is, in the example shown in fig. 5, the heat transfer pipe 2 is arranged in a plurality of layers.

The direction perpendicular to the flow direction of the air is defined as the "layer direction". The heat transfer pipe 2A corresponds to a "first heat transfer pipe" of the present invention, and the heat transfer pipe 2B corresponds to a "second heat transfer pipe" of the present invention.

In the heat exchanger 50, in order to suppress frost formation in the flow path portion of air that will eventually escape during frost formation, no heat transfer promoting portions such as slits are provided between the heat transfer tubes 2 in front of and behind the fins 1. The front and rear heat transfer tubes 2 are the

heat transfer tube

2A and 1 or 2 heat transfer tubes 2B closest to the heat transfer tube 2A and above and below the heat transfer tube 2A, with reference to the heat transfer tube 2A on the most upstream side in the air flow for heat exchange. That is, in the heat exchanger 50, the heat transfer promoting portions are not provided in the region between the lower end portions of the heat transfer tubes 2A and the upper end portions of the heat transfer tubes 2B, and in the region between the upper end portions of the heat transfer tubes 2A and the lower end portions of the heat transfer tubes 2B (the region (second region) L shown in fig. 3 and 5, and there are 3 regions L in fig. 3 and 5).

However, since the heat exchanger 50 shown in fig. 5 has a 3-row structure, the region L is elongated in the row direction, and no heat transfer promoting portion is provided between the lower end portion of the heat transfer tube 2C and the upper end portion of the heat transfer tube 2B. The region L is set to a region including at least the lower end portion of the heat transfer tubes 2A and the central portion of the upper end portion of the heat transfer tubes 2B.

On the other hand, in the heat exchanger 50, the heat transfer promoting portions 3 such as slits for exhibiting the heat transfer promoting effect are formed in the regions (first regions) of the fins 1 not including the regions L. However, the region of the fin 1 not including the region L may be a region in which the heat transfer promoting portion 3 can be formed, and the heat transfer promoting portion 3 does not need to be formed. In addition, δ 2 described below forms the heat transfer promoting portion 3 in a region of the fin 1 not including the region L.

Thus, even if frost grows in the heat exchanger 50, the region L can be secured as an air escape path. In particular, even if frost grows in the heat transfer tubes 2A, the region L functions as an air escape path, and therefore the air reaches the downstream of the heat exchanger 50 and continues heat exchange. Therefore, according to the heat exchanger 50, deterioration of frost resistance can be suppressed.

On the other hand, in the heat exchanger 50, the heat transfer promoting portion 3 can be formed in a region not including the region L, and heat transfer can be promoted by forming the heat transfer promoting portion 3.

In fig. 3 and 5, the region L is shown by way of example as being parallel to the column direction, but the region L need not be strictly parallel. For example, the region L may be secured to be inclined from the upstream toward the downstream of the air flow. In this case, the region L also functions as a drainage path when the frost melts. That is, the region L may include the central portions of the lower end portions of the heat transfer tubes 2A (heat transfer tubes 2C) and the upper end portions of the heat transfer tubes 2B, and the central portions of the upper end portions of the heat transfer tubes 2A (heat transfer tubes 2C) and the lower end portions of the heat transfer tubes 2B, and may or may not be parallel to the row direction.

In addition, the region L may be provided in a part. For example, as shown in fig. 4, a region L may be defined between the uppermost heat transfer tube 2A and the uppermost heat transfer tube 2B. Alternatively, although not shown, the space between the heat transfer tubes 2A of the lowermost layer and the heat transfer tubes 2B of the lowermost layer may be set as the region L. That is, the number of the regions L is not particularly limited. However, when the regions L are set on both the upper and lower sides of the heat exchanger tube as shown in fig. 3 and 5, the deterioration of frost resistance can be further suppressed. Further, if the region L is set between the

heat transfer tubes

2A and 2B in the lowermost layer, the absence of the heat transfer promoting portions 3 increases the drainage property, and the drainage property after defrosting improves.

In addition to the heat exchanger 50, the size of the region L is preferably determined in consideration of the length (δ 1) of the stagnation region around the heat transfer tubes 2. The portion δ 1 is a portion where the frost formation amount is originally small due to peeling of the air flow from the leading edge portion of the heat transfer pipe 2. That is, the region L is set to a range other than the portion of δ 1. This can form the heat transfer promoting portion 3 in the portion δ 1, promote heat transfer in the portion δ 1, and ensure an air escape path in the region L in terms of width.

In addition to the heat exchanger 50, it is preferable that the region other than the region L, that is, the region where the heat transfer promoting portion 3 is formed be determined in consideration of the stagnation region length (δ 2) of the wake flow of the heat transfer tube 2. The section δ 2 is a wake portion of the heat transfer pipe 2, and is a portion where air is originally hard to flow. That is, the heat transfer promoting portion 3 is not formed in the region L, and the heat transfer promoting portion 3 is formed in the region including δ 2. Thus, the heat transfer promoting portion 3 is formed in the portion δ 2, and heat transfer is promoted in the portion δ 2, so that the air can escape through the region L in terms of width. In this case, the region L may include δ 1 or may not include δ 1, and both of them may be included.

As described above, according to the heat exchanger 50, the formation of the region L ensures an escape path of air during frosting, and thus can suppress a decrease in frost resistance. Therefore, the heat exchanger 50 can continue the operation because the air passage is not closed even when frost forms.

Embodiment 2.

Fig. 8 is a refrigerant circuit diagram schematically showing a basic refrigerant circuit configuration of a refrigeration cycle apparatus 100 according to embodiment 2 of the present invention. The configuration and operation of the refrigeration cycle apparatus 100 will be described with reference to fig. 8. The refrigeration cycle apparatus 100 includes the heat source unit 60 and the indoor unit 70, and is capable of performing a heating energy supply operation (for example, a heating operation) or a cooling energy supply operation (for example, a cooling operation) by circulating a refrigerant through component devices mounted on the heat source unit 60 and the indoor unit 70. In embodiment 2, the same components as those in embodiment 1 are denoted by the same reference numerals, and description thereof is omitted.

The indoor unit (also referred to as an indoor unit, a user-side device (user-side unit), or a load-side machine (load-side unit)) 70 constitutes a part of the refrigeration cycle apparatus 100 together with the heat source machine 60. The refrigerant circuit is formed by connecting the unit devices (the compressor 10, the heat exchanger 50, the expansion valve 12, and the use side heat exchanger 71) mounted on the heat source unit 60 and the indoor unit 70 by pipes. The refrigeration cycle apparatus 100 is used, for example, when performing an air conditioning operation of an air-conditioning target space (an indoor space in which the indoor unit 70 is installed, or the like). The refrigeration cycle apparatus 100 is used, for example, when a hot water supply operation is performed in which water is boiled to hot water by the use-side heat exchanger 71. However, in embodiment 2, a case where the refrigeration cycle apparatus 100 performs an air-conditioning operation will be described.

The heat source unit 60 is as described in embodiment 1.

The indoor unit 70 is mounted with a use side heat exchanger 71 and an air blowing fan 72.

The use-side heat exchanger (also referred to as an indoor heat exchanger or a load-side heat exchanger) 71 may be a cross-fin-and-tube heat exchanger, similar to the heat exchanger 50. However, in the case of performing heat exchange with water, brine, or the like, the use-side heat exchanger 71 may be configured by a microchannel heat exchanger, a shell-and-tube heat exchanger, a heat pipe heat exchanger, a double-tube heat exchanger, a plate heat exchanger, or the like. Here, a case where the use-side heat exchanger 71 exchanges heat with the refrigerant by air will be described as an example.

The air blowing fan 72 is an air blowing mechanism constituted by a straight flow fan (cross flow fan), for example.

The air-conditioning operation of the refrigeration cycle apparatus 100 will be described.

[ heating operation ]

When the compressor 10 is driven, the refrigerant is pressurized by the compressor 10, and discharged in a high-temperature and high-pressure state. The refrigerant discharged from the compressor 10 is supplied to the use side heat exchanger 71, and is cooled by heat exchange with air, and is brought into a low-temperature and high-pressure state. At this time, air for heating is supplied from the indoor unit 70, and the space to be air-conditioned is heated. The refrigerant flows out of the use side heat exchanger 71, is expanded and decompressed by the expansion valve 12, and is brought into a low-temperature and low-pressure state. The refrigerant is heated by the heat exchanger 50 and then returns to the compressor 10 again.

[ Cooling operation ]

When the compressor 10 is driven, the refrigerant is pressurized by the compressor 10, and discharged in a high-temperature and high-pressure state. The refrigerant discharged from the compressor 10 is supplied to the heat exchanger 50, and is cooled by heat exchange with air, thereby being in a low-temperature and high-pressure state. The refrigerant flows out of the heat exchanger 50, is expanded and decompressed by the expansion valve 12, and is brought into a low-temperature and low-pressure state. The refrigerant is heated by the use side heat exchanger 71. At this time, air for cooling is supplied from the indoor unit 70, and the space to be air-conditioned is cooled. The refrigerant flowing out of the use side heat exchanger 71 returns to the compressor 10 again.

As described above, since the refrigeration cycle apparatus 100 includes the heat exchanger 50, an air escape path can be secured even when frost is formed, and a decrease in frost resistance can be suppressed. In the refrigeration cycle apparatus 100, even when the heat exchanger 50 is frosted, the air passage of the heat exchanger 50 is not closed, and therefore the heating energy supply operation can be continuously performed.

The numerical values described in embodiment 1 are merely examples, and are not limited to the numerical values described.

Description of the symbols

1 fin, 1A fin, 1B fin, 1C fin, 2 heat transfer tube, 2A heat transfer tube, 2B heat transfer tube, 2C heat transfer tube, 3 heat transfer promoting portion, 10 compressor, 11 four-way valve, 12 expansion valve, 15 refrigerant piping, 16 muffler, 20 blower fan, 21 fan motor, 22 motor support, 50 heat exchanger, 60 heat source machine, 60A frame, 61 partition plate, 62 machine room, 63 blower room, 70 indoor unit, 71 utilization side heat exchanger, 72 blower fan, 100 refrigeration cycle device, L region.

Claims

1. A heat exchanger having a plurality of fins arranged in parallel at predetermined intervals and a heat transfer tube penetrating the plurality of fins, the plurality of fins having a multi-row structure, the heat transfer tube being arranged in a plurality of layers in a direction orthogonal to a row direction of the plurality of fins,

the heat exchanger is characterized in that it is provided with,

the heat transfer pipe includes: a first heat transfer pipe that penetrates the fins of the first row when viewed from the most upstream side of the air flow flowing through the heat exchanger; and a second heat transfer pipe which penetrates the fins of the second row, is closest to the first heat transfer pipe, and is located above and below the first heat transfer pipe in the layer direction,

a first region and a second region are provided on the first row of fins and the second row of fins arranged in the row direction, the first region having a slit formed at least in a part thereof, the second region not having the slit formed therein,

the second region is provided in at least one of a region between the lower end portion of the first heat transfer pipe and the upper end portion of the second heat transfer pipe and a region between the upper end portion of the first heat transfer pipe and the lower end portion of the second heat transfer pipe, and is a flat surface portion that is continuous in the row direction on the fins in the first row and the fins in the second row and extends in the direction of the air flow from the windward direction of the fins in the first row to the leeward direction of the fins in the second row,

the width of the second region in the layer direction is larger than the width of the first region in the layer direction.

2. The heat exchanger of claim 1,

the first region is a region independent from the second region.

3. The heat exchanger according to claim 1 or 2,

the second region includes at least a central portion between a lower end portion of the first heat transfer pipe and an upper end portion of the second heat transfer pipe.

4. The heat exchanger according to any one of claims 1 to 3,

the second region includes at least a central portion between an upper end portion of the first heat transfer pipe and a lower end portion of the second heat transfer pipe.

5. The heat exchanger according to any one of claims 1 to 4,

the second region is a region other than the length of the stagnation region around the heat transfer pipe.

6. The heat exchanger according to any one of claims 1 to 5,

the first region is a region including a length of a stagnation region of a wake of the heat transfer pipe, and at least the slit is formed in the region.

7. A refrigeration cycle device is characterized by comprising:

a heat source unit on which the heat exchanger according to any one of claims 1 to 6 is mounted; and

and a utilization-side device connected to the heat source unit.