WO2024018977A1

WO2024018977A1 - Heat exchanger and refrigerant cycle device

Info

Publication number: WO2024018977A1
Application number: PCT/JP2023/025812
Authority: WO
Inventors: 航寺井; 知恵江村; 健佐藤; 信哉田端
Original assignee: ダイキン工業株式会社
Priority date: 2022-07-19
Filing date: 2023-07-13
Publication date: 2024-01-25
Also published as: JP2024013036A

Abstract

In a heat exchanger (100), a refrigerant flows in the longitudinal direction (DL) between an upper second flow hole (120b) and a lower second flow hole (120b). The heat exchanger (100) comprises a first heat transfer plate (110) and a second heat transfer plate (120) which form N flow channel regions (F1-F5) arranged next to each other in the longitudinal direction (DL). The number and cross-sectional areas of the flow channels in the first flow channel region (F1) are different from the number and cross-sectional areas of the flow channels in the Nth flow channel region (F5). The first flow channel region (F1) is located first among the N flow channel regions in the longitudinal direction (DL) from the upper second flow hole (120b) side. The Nth flow channel region (F5) is located Nth among the N flow channel regions in the longitudinal direction (DL) from the upper second flow hole (120b) side.

Description

Heat exchanger and refrigerant cycle equipment

Regarding heat exchangers and refrigerant cycle devices.

Conventionally, a heat exchanger is used that includes a heat transfer member in which a plurality of heat exchange passages for exchanging heat with a fluid and branch passages for distributing the fluid to each heat exchange passage are formed. .

Patent Document 1 (Japanese Unexamined Patent Publication No. 2016-90157) discloses a plate fin type including a metal plate in which a plurality of heat exchange channels and a pair of branch channels connected to both ends of the heat exchange channels are formed. A heat exchanger is disclosed. In such conventional heat exchangers, the fluid introduced into the heat exchanger is divided into all heat exchange channels by branch channels near the inlet of the heat exchanger, and the fluid is divided into branch channels near the outlet of the heat exchanger. They are joined by roads. Therefore, the number and cross-sectional area of heat exchange channels are often constant from near the inlet to near the outlet of the heat exchanger. In this case, pressure loss may increase in the heat exchange channel near the inlet through which the gaseous fluid flows, and the performance of the heat exchanger may deteriorate. Furthermore, the flow velocity of the fluid may decrease in the heat exchange channel near the outlet through which the liquid fluid flows, and the heat transfer efficiency may decrease.

The heat exchanger of the first aspect is a heat exchanger in which a fluid flows in a first direction between a first opening and a second opening. The heat exchanger is a member that forms N flow path areas (N is an integer of 2 or more) that are arranged adjacent to each other along the first direction between the first opening and the second opening. Equipped with. Each of the N channel regions has a channel through which fluid flows. The number of channels and the cross-sectional area of the first channel region are different from the number of channels and the cross-sectional area of the Nth channel region. The first channel region is located first from the first opening side in the first direction among the N channel regions. The Nth channel region is located Nth from the first opening side in the first direction among the N channel regions.

In the heat exchanger of the first aspect, the flow path through which the fluid flows is formed so that a suitable fluid flow rate is achieved according to the phase change (density change) of the fluid flowing inside the heat exchanger. Therefore, the performance of the heat exchanger is prevented from deteriorating due to an increase in pressure loss in the flow path near the inlet through which the gaseous fluid flows. Furthermore, a decrease in heat transfer efficiency due to a decrease in the flow velocity of the fluid in the flow path near the outlet through which the liquid fluid flows is suppressed.

The heat exchanger according to the second aspect is the heat exchanger according to the first aspect, in which the number of channels in the i-th channel region is smaller than the number of channels in the j-th channel region, and the number of channels in the i-th channel region is smaller than the number of channels in the j-th channel region. The cross-sectional area of the flow path in the flow path region is larger than the cross-sectional area of the flow path in the j-th flow path region. The i-th channel region is located i-th from the first opening side in the first direction among the N channel regions. The j-th flow path area is located at the j-th position from the first opening side in the first direction among the N flow path areas (i, j are integers satisfying 1≦i<j≦N). do.

In the heat exchanger according to the second aspect, the cross-sectional area of the flow path gradually decreases from the gas side (inlet side) to the liquid side (outlet side), so the pressure loss on the gas side is reduced, and the pressure loss on the liquid side is reduced. The fluid flow rate is ensured. Furthermore, since the number of flow paths gradually increases from the gas side to the liquid side, even if the cross-sectional area of the flow paths decreases from the gas side to the liquid side, the reduction in the heat transfer area of the fluid can be suppressed.

The heat exchanger of the third aspect is the heat exchanger of the first aspect or the second aspect, and the number of channels in the first channel region is one.

The heat exchanger of the fourth aspect is the heat exchanger of the third aspect, and the distance L1 and the distance L0 satisfy the relational expression 0.2×L0≦L1≦0.8×L0. The distance L1 is the distance in the first direction between the boundary between the second flow path area and the first flow path area and the first opening. The distance L0 is the distance in the first direction between the first opening and the second opening. The second channel region is located second from the first opening side in the first direction among the N channel regions.

The heat exchanger of the fifth aspect is the heat exchanger of the fourth aspect, and the distance L2 and the distance L0 satisfy the relational expression 0.2×L0≦L2≦0.8×L0. The distance L2 is the distance in the first direction between the first opening and the boundary between two flow path regions adjacent in the first direction among the N flow path regions. The distance L0 is the distance in the first direction between the first opening and the second opening.

The heat exchanger according to the sixth aspect is the heat exchanger according to any one of the first to fifth aspects, and the flow path is branched at the boundary between the kth flow path region and the k+1th flow path region. However, the number of channels in the k+1th channel region is twice to four times the number of channels in the k-th channel region. The k-th flow path region is located at the k-th (k is an integer satisfying 1≦k≦N−1) from the first opening side in the first direction among the N flow path regions. The (k+1)th flow path area is located at the (k+1)th position from the first opening side in the first direction among the N flow path areas.

The heat exchanger according to the seventh aspect is the heat exchanger according to any one of the first to sixth aspects, and the length in the first direction of each of the N flow path regions is the same as that between the first opening and the second opening. It is 10% to 50% of the distance in the first direction from the opening.

The heat exchanger according to the eighth aspect is the heat exchanger according to any one of the first to seventh aspects, and includes a plurality of members stacked in a second direction intersecting the first direction. N flow path regions are formed between adjacent members in the second direction.

The heat exchanger according to the ninth aspect is the heat exchanger according to the eighth aspect, and includes N flow path areas each having a flow path through which a first medium, which is a fluid, flows, and a flow path through which a second medium, which is a fluid, flows. N flow path regions having N flow path regions are alternately stacked in the second direction. The first medium flows through the channel from the first opening toward the second opening. The second medium flows through the channel from the second opening toward the first opening.

A refrigerant cycle device according to a tenth aspect includes the heat exchanger according to any one of the first to ninth aspects.

1 is a schematic configuration diagram of a refrigerant cycle device 1 including a heat exchanger 100. FIG. 1 is an exploded perspective view of a heat exchanger 100. FIG. 1 is a cross-sectional view of a heat exchanger 100. FIG. 3 is a plan view of the first heat transfer plate 110. FIG. 3 is a plan view of the second heat transfer plate 120. FIG. 3 is a plan view of the second heat transfer plate 120. FIG. 7 is a plan view of a second heat transfer plate 120 in modification A. FIG. 7 is a plan view of a second heat transfer plate 120 in modification B. FIG.

(1) Refrigerant cycle device 1
A refrigerant cycle device 1 including a heat exchanger 100 according to an embodiment of the present disclosure will be described. The refrigerant cycle device 1 is a dual refrigeration device that cools an air-conditioned space (not shown) such as an indoor room of a building by executing a vapor compression cycle.

As shown in FIG. 1, the refrigerant cycle device 1 includes a heat source side cycle 10 and a utilization side cycle 20. The heat source side cycle 10 is a vapor compression type cycle that circulates a refrigerant. The refrigerant is, for example, R1234ze. The utilization side cycle 20 is a vapor compression type cycle that circulates a heat medium that is a fluid with a lower boiling point than the refrigerant. The heat medium is, for example, carbon dioxide. Heat exchange between the refrigerant and the heat medium is performed in the heat exchanger 100.

(1-1) Heat exchanger 100
The heat exchanger 100 is a cascade condenser that exchanges heat between a refrigerant and a heat medium. The heat exchanger 100 functions as a refrigerant evaporator and a heat medium condenser. The heat exchanger 100 has a first inlet pipe 150a, a first outlet pipe 150b, a second inlet pipe 160a, a second outlet pipe 160b, a first flow path 111, and a second flow path 121.

The first flow path 111 is a flow path through which the refrigerant flows. The first flow path 111 is formed between the first introduction pipe 150a and the first outlet pipe 150b. The second flow path 121 is a flow path through which a heat medium flows. The second flow path 121 is formed between the second introduction pipe 160a and the second outlet pipe 160b. The detailed structure of the heat exchanger 100 will be described later.

(1-2) Heat source side cycle 10
The heat source side cycle 10 includes a heat source side compressor 11, a heat source side heat exchanger 12, a heat source side expansion valve 13, a first inlet pipe 150a of the heat exchanger 100, a first outlet pipe 150b, and a first flow path. 111. The heat source side cycle 10 is installed outside the air-conditioned space.

The heat source side compressor 11 sucks the low-pressure gas-phase refrigerant in the heat-source side cycle 10 from the first suction part 11a, compresses it, and discharges it as a high-pressure gas-phase refrigerant from the first discharge part 11b. The heat source side heat exchanger 12 functions as a condenser, and exchanges heat between the refrigerant and the outside air (air outside the air-conditioned space). The heat source side expansion valve 13 adjusts the flow rate of the refrigerant circulating through the heat source side cycle 10. The heat source side expansion valve 13 functions as a pressure reducing device that reduces the pressure of the refrigerant.

The first discharge part 11b of the heat source side compressor 11 is connected to one end of the heat source side heat exchanger 12. The other end of the heat source side heat exchanger 12 is connected to one end of the heat source side expansion valve 13. The other end of the heat source side expansion valve 13 is connected to the first introduction pipe 150a of the heat exchanger 100. The first outlet pipe 150b of the heat exchanger 100 is connected to the first suction part 11a of the heat source side compressor 11.

(1-3) User cycle 20
The usage cycle 20 includes a usage compressor 21, a usage heat exchanger 22, a usage expansion valve 23, a second inlet pipe 160a, a second outlet pipe 160b, and a second flow path of the heat exchanger 100. 121. The user-side cycle 20 is installed in an air-conditioned space.

The usage-side compressor 21 sucks in the low-pressure gas-phase heat medium in the usage-side cycle 20 from the second suction part 21a, compresses it, and discharges it as a high-pressure gas-phase heat medium from the second discharge part 21b. The user-side heat exchanger 22 functions as an evaporator, and exchanges heat between the heat medium and the air in the air-conditioned space. The usage-side expansion valve 23 adjusts the flow rate of the heat medium circulating through the usage-side cycle 20. The utilization side expansion valve 23 functions as a pressure reducing device that reduces the pressure of the heat medium.

The second discharge part 21b of the user-side compressor 21 is connected to the second introduction pipe 160a of the heat exchanger 100. The second outlet pipe 160b of the heat exchanger 100 is connected to one end of the usage-side expansion valve 23. The other end of the usage-side expansion valve 23 is connected to one end of the usage-side heat exchanger 22. The other end of the utilization side heat exchanger 22 is connected to the first suction section 11a of the utilization side compressor 21.

(1-4) Operation The operation of the heat source side cycle 10 and the usage side cycle 20 while the refrigerant cycle device 1 is in operation will be explained. When the refrigerant cycle device 1 starts operating, a control unit (not shown) drives the heat source side compressor 11 and the usage side compressor 21, and adjusts the opening degrees of the heat source side expansion valve 13 and the usage side expansion valve 23 to match the air conditioning load. Set the appropriate opening according to the

(1-4-1) Operation of heat source side cycle 10 The heat source side compressor 11 sucks the low-pressure gas phase refrigerant in the heat source side cycle 10 from the first suction part 11a, and converts it into a high-pressure gas phase refrigerant to the first discharge part. It is discharged from 11b. The refrigerant in the high-pressure gas phase reaches the heat source side heat exchanger 12 . The heat source side heat exchanger 12 condenses high-pressure gas phase refrigerant into high-pressure liquid phase refrigerant. At this time, the refrigerant releases heat to the outside air. The high-pressure liquid phase refrigerant reaches the heat source side expansion valve 13 . The heat source side expansion valve 13, which is set to an appropriate opening degree, reduces the pressure of the high-pressure liquid phase refrigerant and converts it into a low-pressure gas-liquid two-phase refrigerant. The low-pressure gas-liquid two-phase refrigerant passes through the first introduction pipe 150a of the heat exchanger 100 and enters the first flow path 111. The heat exchanger 100 evaporates a low-pressure gas-liquid two-phase refrigerant into a low-pressure gas-phase refrigerant. At this time, the refrigerant absorbs heat from the heat medium passing through the second flow path 121 of the heat exchanger 100. The low-pressure gas phase refrigerant passes through the first outlet pipe 150b, exits the first flow path 111, and is sucked into the heat source side compressor 11 from the first suction portion 11a.

(1-4-2) Operation of the utilization side cycle 20 The utilization side compressor 21 sucks the low-pressure gas-phase heat medium in the utilization-side cycle 20 from the second suction part 21a, and uses it as a high-pressure gas-phase heat medium as a second suction medium. It is discharged from the discharge part 21b. The high-pressure gas phase heat medium passes through the second introduction pipe 160a of the heat exchanger 100 and enters the second flow path 121. The heat exchanger 100 condenses a high-pressure gas-phase heat medium into a high-pressure liquid-phase heat medium. At this time, the heat medium releases heat to the refrigerant passing through the first flow path 111 of the heat exchanger 100. The high-pressure liquid phase heat medium passes through the second outlet pipe 160b, exits the second flow path 121, and reaches the usage-side expansion valve 23. The usage-side expansion valve 23, which is set to an appropriate opening degree, reduces the pressure of the high-pressure liquid-phase heat medium and converts it into a low-pressure gas-liquid two-phase heat medium. The low-pressure gas-liquid two-phase heat medium reaches the utilization side heat exchanger 22 . The utilization side heat exchanger 22 evaporates the low-pressure gas-liquid two-phase heat medium into a low-pressure gas-phase heat medium. At this time, the heat medium absorbs heat from the air within the air-conditioned space. The heat medium in the low-pressure gas phase exits the usage-side heat exchanger 22 and is sucked into the usage-side compressor 21 from the second suction section 21a.

(2) Heat exchanger 100
(2-1) Overall configuration As shown in FIG. 2, the heat exchanger 100 includes a plurality of first heat transfer plates 110, a plurality of second heat transfer plates 120, a first frame 130, and a second frame. 140. The heat exchanger 100 has a first flow path 111 and a second flow path 121 formed therein.

The first heat transfer plate 110 and the second heat transfer plate 120 are metal plate members having the same rectangular outer shape. In this embodiment, as shown in FIG. 2, the first heat transfer plate 110, the second heat transfer plate 120, the first frame 130, and the second frame 140 are formed in a rectangular shape extending along the longitudinal direction DL. has been done.

The plurality of first heat transfer plates 110 and the plurality of second heat transfer plates 120 are alternately stacked between the first frame 130 and the second frame 140. The number of each of the plurality of first heat transfer plates 110 and the plurality of second heat transfer plates 120 is not limited, and is appropriately set according to the required performance. The materials and dimensions of the first frame 130, the first heat transfer plate 110, the second heat transfer plate 120, and the second frame 140 are not limited, and are appropriately set according to the required performance. The first frame 130, the first heat transfer plate 110, the second heat transfer plate 120, and the second frame 140 are integrally joined by, for example, brazing.

In the following description, the direction in which the first heat transfer plate 110 and the second heat transfer plate 120 are stacked is called the stacking direction DS, and the direction perpendicular to the longitudinal direction DL and the stacking direction DS is called the width direction DW. Further, as shown in FIG. 2, the directions of "top", "bottom", "left", "right", "front", and "back" are defined. The longitudinal direction DL is an up-down direction. The width direction DW is the left-right direction. The stacking direction DS is the front-back direction.

(2-2) Detailed configuration (2-2-1) First heat transfer plate 110
The first heat transfer plate 110 is a corrugated fin having a corrugated cross section. In the present embodiment, as shown in FIGS. 2 and 3, the waveform of the first heat transfer plate 110 is formed so that the top portion thereof draws a herringbone pattern convex upward in plan view.

The first heat transfer plate 110 forms a first flow path 111 and a second flow path 121 together with the second heat transfer plate 120 stacked adjacently. The first heat transfer plate 110 has a first joint region 110a, two first communication holes 110b, two first through holes 110c, a first front surface 110sa, and a first rear surface 110sb.

The first bonding region 110a is a region for bonding the first heat transfer plate 110 and the second heat transfer plate 120 to each other. The first joint region 110a is a band-shaped region with an edge of a predetermined width bent toward the front side.

The first flow hole 110b is a circular hole that introduces or leads the refrigerant into the first flow path 111. The first communication hole 110b is formed on the upper left side and the lower right side of the first heat transfer plate 110.

The first through hole 110c is a circular hole that allows the heat medium to pass in the stacking direction DS. The first through hole 110c is formed on the upper right side and the lower left side of the first heat transfer plate 110.

The first front surface 110sa is the front surface of the first heat transfer plate 110. The first front surface 110sa is a surface that faces a second rear surface 120sb of the second heat transfer plate 120, which will be described later, when the first heat transfer plate 110 and the second heat transfer plate 120 are stacked.

The first rear surface 110sb is the rear surface of the first heat transfer plate 110. The first rear surface 110sb is a surface that faces a second front surface 120sa of the second heat transfer plate 120, which will be described later, when the first heat transfer plate 110 and the second heat transfer plate 120 are stacked.

The first heat transfer plate 110 is formed using, for example, press working, although the manufacturing method is not limited.

(2-2-2) Second heat transfer plate 120
The second heat transfer plate 120 forms a first flow path 111 and a second flow path 121 together with the first heat transfer plate 110 stacked adjacent to each other. The second heat transfer plate 120 has a second bonding region 120a, two second communication holes 120b, two second through holes 120c, a second front surface 120sa, and a second rear surface 120sb.

The second bonding region 120a is a region for bonding the first heat transfer plate 110 and the second heat transfer plate 120 to each other. The second joint region 120a is a band-shaped region with a predetermined width edge bent toward the front.

The second flow hole 120b is a circular hole that introduces or leads out the heat medium to the second flow path 121. The second communication hole 120b is formed on the upper right side and the lower left side of the second heat transfer plate 120. The second communication hole 120b is formed at a position that overlaps and communicates with the first through hole 110c when the first heat transfer plate 110 and the second heat transfer plate 120 are stacked. The size and shape of the second communication hole 120b are the same as the first through hole 110c.

The second through hole 120c is a circular hole that allows the refrigerant to pass in the stacking direction DS. The second through hole 120c is formed on the upper left side and the lower right side of the second heat transfer plate 120. The second through hole 120c is formed at a position that overlaps and communicates with the first communication hole 110b when the first heat transfer plate 110 and the second heat transfer plate 120 are stacked. The size and shape of the second through hole 120c are the same as the first communication hole 110b.

The second front surface 120sa is the front surface of the second heat transfer plate 120. The second front surface 120sa is a surface that faces the first rear surface 110sb of the first heat transfer plate 110 when the first heat transfer plate 110 and the second heat transfer plate 120 are stacked.

The second rear surface 120sb is the rear surface of the second heat transfer plate 120. The second rear surface 120sb is a surface that faces the first front surface 110sa of the first heat transfer plate 110 when the first heat transfer plate 110 and the second heat transfer plate 120 are stacked.

The second heat transfer plate 120 is formed using, for example, press working, although the manufacturing method is not limited. Details of the shape of the second heat transfer plate 120 will be described later.

(2-2-3) First frame 130 and second frame 140
The first frame 130 and the second frame 140 are metal plate-like members that sandwich the plurality of first heat transfer plates 110 and the plurality of second heat transfer plates 120, which are stacked alternately, at both ends in the stacking direction DS. be.

(2-2-4) First inlet pipe 150a and first outlet pipe 150b
The first introduction pipe 150a is a pipe that introduces the refrigerant into the first flow path 111. The first introduction pipe 150a is provided to pass through the upper left side of the first frame 130 and communicate with the first flow path 111. More specifically, the first introduction pipe 150a is a first communication hole formed on the upper left side that communicates with each other when the first heat transfer plate 110, the second heat transfer plate 120, and the first frame 130 are stacked. 110b and the second through hole 120c.

The first outlet pipe 150b is a pipe that leads out the refrigerant from the first flow path 111. The first outlet pipe 150b is provided to penetrate the lower right side of the first frame 130 and communicate with the first flow path 111. More specifically, the first outlet pipe 150b is a first communication hole formed on the lower right side that communicates with each other when the first heat transfer plate 110, the second heat transfer plate 120, and the first frame 130 are stacked. 110b and the second through hole 120c.

(2-2-5) Second introduction pipe 160a and second outlet pipe 160b
The second introduction pipe 160a is a pipe that introduces the heat medium into the second flow path 121. The second introduction pipe 160a is provided to pass through the upper right side of the first frame 130 and communicate with the second flow path 121. More specifically, the second introduction pipe 160a is a second communication hole formed on the upper right side that communicates with each other when the first heat transfer plate 110, the second heat transfer plate 120, and the first frame 130 are stacked. 120b and the first through hole 110c.

The second outlet pipe 160b is a pipe that leads out the heat medium from the second flow path 121. The second outlet pipe 160b is provided to penetrate the lower left side of the first frame 130 and communicate with the second flow path 121. More specifically, the second introduction pipe 160a is a second communication hole formed on the lower left side that communicates with each other when the first heat transfer plate 110, the second heat transfer plate 120, and the first frame 130 are stacked. 120b and the first through hole 110c.

(2-2-6) First flow path 111 and second flow path 121
As shown in FIG. 3, by alternately stacking the first heat transfer plates 110 and the second heat transfer plates 120, first flow channels 111 and second flow channels 121 are formed alternately in the stacking direction DS. be done. More specifically, the first heat transfer plate 110 and the second heat transfer plate 120 are stacked alternately, so that the first front surface 110sa of the first heat transfer plate 110 and the second rear surface of the second heat transfer plate 120 are stacked alternately. The space where 120sb faces becomes the first flow path 111. Furthermore, by alternately stacking the first heat transfer plate 110 and the second heat transfer plate 120, the first rear surface 110sb of the first heat transfer plate 110 and the second front surface 120sa of the second heat transfer plate 120 are mutually connected. The opposing space becomes the second flow path 121.

The first heat transfer plate 110 and the second heat transfer plate 120 are joined by brazing. More specifically, in the first heat transfer plate 110 and the second heat transfer plate 120, the first bonding area 110a and the second bonding area 120a are bonded to each other by brazing.

In the following description, the first flow path 111 is located between the first communication hole 110b on the upper side and the first communication hole 110b on the lower side, and has a rectangular shape whose dimension in the width direction DW is constant in the longitudinal direction DL. represents the area of Similarly, the second flow path 121 is located between the upper second flow hole 120b and the lower second flow hole 120b, and is a rectangular region whose dimension in the width direction DW is constant in the longitudinal direction DL. represents. 4 and 5 show the ranges of the first flow path 111 and the second flow path 121 in the longitudinal direction DL and the width direction DW, respectively.

(2-3) Flow of refrigerant and heat medium The refrigerant introduced from the first introduction pipe 150a of the heat exchanger 100 passes through the upper second through hole 120c and the first distribution hole 110b and enters the first flow path 111. flows into. The refrigerant that has flowed into the first flow path 111 flows through the first flow path 111 toward the first flow hole 110b on the lower side. The refrigerant that has reached the first flow hole 110b on the lower side passes through the second through hole 120c on the lower side and is led out from the first outlet pipe 150b. During this time, the liquid refrigerant flowing through the first flow path 111 exchanges heat with the heat medium in the adjacent second flow path 121 via the first heat transfer plate 110 or the second heat transfer plate 120, and evaporates. It becomes a gaseous refrigerant. In other words, the heat exchanger 100 functions as a refrigerant evaporator.

On the other hand, the heat medium introduced from the second introduction pipe 160a of the heat exchanger 100 flows into the second flow path 121 through the upper second communication hole 120b and the first through hole 110c. The heat medium that has flowed into the second flow path 121 flows through the second flow path 121 toward the second flow hole 120b on the lower side. The heat medium that has reached the second flow hole 120b on the lower side passes through the first through hole 110c on the lower side and is led out from the second outlet pipe 160b. During this time, the gaseous heat medium flowing through the second flow path 121 exchanges heat with the refrigerant in the adjacent first flow path 111 via the first heat transfer plate 110 or the second heat transfer plate 120, and is condensed. , becomes a liquid heat medium. In other words, the heat exchanger 100 functions as a heat medium condenser.

(2-4) Detailed configuration of second flow path 121 In the heat exchanger 100, the heat medium flowing through the second flow path 121 is distributed between the upper second flow hole 120b and the lower second flow hole 120b. flows along the longitudinal direction DL. In this embodiment, the heat medium flows in from the upper second flow hole 120b, passes through the second flow path 121, and then flows out from the lower second flow hole 120b. The upper second communication hole 120b communicates with the second introduction pipe 160a via the upper first through hole 110c. The second flow hole 120b on the lower side communicates with the second outlet pipe 160b via the first through hole 110c on the lower side. The gaseous heat medium before being heat exchanged in the heat exchanger 100 flows from the second introduction pipe 160a into the second flow path 121 through the upper second communication hole 120b. In the process of passing through the second flow path 121, the gaseous heat medium undergoes heat exchange and becomes liquid. After flowing out of the second flow path 121, the liquid heat medium passes through the second flow hole 120b on the lower side and is supplied to the second outlet pipe 160b.

The first heat transfer plate 110 and the second heat transfer plate 120 form N flow path regions. The value N is an integer greater than or equal to 2. In this embodiment, as shown in FIG. 6, the value N is 5, and the first heat transfer plate 110 and the second heat transfer plate 120 form five flow path regions F1 to F5. Each flow path region F1 to F5 has a portion of the second flow path 121. Each of the flow path regions F1 to F5 is a rectangular region arranged adjacent to each other along the longitudinal direction DL between the upper second flow hole 120b and the lower second flow hole 120b. The dimension in the width direction DW of each flow path region F1 to F5 is equal to the dimension in the width direction DW of the second flow path 121.

In the following description, among the N channel regions, the channel region located xth from the upper second communication hole 120b side in the longitudinal direction DL will be referred to as the x-th channel region. The value x is an integer satisfying 1≦x≦N. For example, in FIG. 6, the first flow path area F1 is located below the upper second flow hole 120b, and the second flow path area F2 is located below the first flow path area F1. Further, the fifth flow path area F5 (Nth flow path area) is located below the fourth flow path area F4 and above the second flow hole 120b on the lower side. In this way, the first to Nth flow path regions are arranged adjacent to each other in a line along the longitudinal direction DL from the second communication hole 120b on the upper side toward the second communication hole 120b on the lower side. .

Each flow path region F1 to F5 has one or more flow path elements 131. The flow path element 131 is a space through which the heat medium flows along the longitudinal direction DL. When the channel region has a plurality of channel elements 131, the plurality of channel elements 131 are arranged along the width direction DW. Two channel elements 131 adjacent in the width direction DW are partitioned by a partition element 132 extending along the longitudinal direction DL. In FIGS. 5-8, the partitioning elements 132 are shown as hatched areas.

As shown in FIG. 3, the channel element 131 corresponds to a space where the first rear surface 110sb of the first heat transfer plate 110 and the second front surface 120sa of the second heat transfer plate 120 are opposed to each other. Further, the partition element 132 corresponds to a portion where the first rear surface 110sb of the first heat transfer plate 110 and the second front surface 120sa of the second heat transfer plate 120 are joined. When the channel region has a plurality of channel elements 131, the plurality of channel elements 131 have the same dimension in the width direction DW and the same cross-sectional area.

Two flow path regions adjacent in the longitudinal direction DL have different numbers of flow path elements 131 and different cross-sectional areas. Further, in each of the flow path regions F1 to F5, the number and cross-sectional area of the flow path elements 131 are constant. Therefore, when N channel regions are formed, the number and cross-sectional area of the channel elements 131 in the first channel region are the same as the number and cross-sectional area of the channel elements 131 in the N-th channel region. It is different from the area.

Specifically, when the values i and j are integers satisfying 1≦i<j≦N, the number of channel elements 131 in the i-th channel region is greater than the number of channel elements 131 in the j-th channel region. , and the cross-sectional area of the flow path element 131 in the i-th flow path region is larger than the cross-sectional area of the flow path element 131 in the j-th flow path region. For example, as shown in FIG. 6, the second flow path area F2 has two flow path elements 131, and the third flow path area F3 has four flow path elements 131. In this case, the dimension in the width direction DW of the channel element 131 in the second channel region F2 is larger than the dimension in the width direction DW of the channel element 131 in the third channel region F3. Therefore, the cross-sectional area of the flow path element 131 in the second flow path area F2 is larger than the cross-sectional area of the flow path element 131 in the third flow path area F3.

Furthermore, in this embodiment, as shown in FIG. 6, the number of flow path elements 131 in the first flow path region F1 is one. In other words, the first flow path region F1 does not have the partition element 132.

Furthermore, in this embodiment, as shown in FIG. 6, a confluence region 133 is provided between the fifth flow path region F5 (Nth flow path region) and the second flow hole 120b on the lower side. It is formed. The confluence region 133 communicates with all flow path elements 131 of the fifth flow path region F5. The dimension of the merging region 133 in the longitudinal direction DL is preferably 20% or less of the dimension of the second flow path 121 in the longitudinal direction DL.

Therefore, the number of flow path elements 131 in the flow path regions F1 to F5 gradually increases from the upper second flow hole 120b to the lower second flow hole 120b, and the number of flow path elements 131 in the flow path regions F1 to F5 gradually increases. The cross-sectional area of channel element 131 gradually decreases. In other words, in the process in which the gaseous heat medium flows through the second flow path 121 and becomes a liquid heat medium, the number of flow path elements 131 through which the heat medium flows gradually increases, and the number of flow path elements 131 is interrupted. The area gradually decreases.

Furthermore, in the second flow path 121, the boundary between two flow path regions adjacent in the longitudinal direction DL is a position where the number and cross-sectional area of the flow path elements 131 change. Therefore, in the second flow path 121, the flow of the heat medium gradually branches during the process in which the heat medium flows from the first flow path region F1 toward the fifth flow path region F5. The heat medium that has passed through the flow path element 131 of the fifth flow path region F5 joins together in the merging region 133 and is supplied to the second flow hole 120b on the lower side.

In FIG. 6, the numbers of channel elements 131 in the first to fifth channel regions F1 to F5 are 1, 2, 4, 8, and 16, respectively. In other words, the number of flow path elements 131 doubles each time the flow of the heat medium branches during the flow of the heat medium from the first flow path region F1 toward the second flow hole 120b on the lower side. ing.

The number of each flow path region F1 to F5, the dimension in the longitudinal direction DL, etc. are not limited, and are appropriately set according to the required performance. Further, the number of flow path elements 131 in each flow path region F1 to F5 is not limited, and is appropriately set according to the required performance. For example, the first flow path area F1 may have one flow path element 131, and the second flow path area F2 may have ten flow path elements 131. In this case, the number of flow path elements 131 doubles each time the flow of the heat medium branches during the process in which the heat medium flows from the second flow path region F2 toward the second flow hole 120b on the lower side. You can leave it there.

(3) Features (3-1)
Conventionally, a plate-fin type heat exchanger has been used, which includes a metal plate in which a plurality of heat exchange channels for exchanging heat with a fluid and a pair of branch channels connected to both ends of the heat exchange channels are formed. It is being In such a heat exchanger, the fluid flowing into the heat exchanger is divided into all heat exchange channels by a branch channel near the inlet of the heat exchanger, and is merged by a branch channel near the outlet of the heat exchanger. do. Therefore, the number and cross-sectional area of the heat exchange channels are constant from near the inlet to near the outlet of the heat exchanger. When a gaseous fluid undergoes a phase change to a liquid fluid due to heat exchange in the heat exchange channel, pressure loss increases in the heat exchange channel near the inlet where the gaseous fluid flows, reducing the performance of the heat exchanger. Sometimes. Furthermore, the flow velocity of the fluid may decrease in the heat exchange channel near the outlet through which the liquid fluid flows, and the heat transfer efficiency may decrease.

The heat exchanger 100 of this embodiment includes first heat transfer plates 110 and second heat transfer plates 120 that are alternately stacked. The first heat transfer plate 110 and the second heat transfer plate 120 form a second flow path 121 in which a gaseous heat medium is condensed through heat exchange to become a liquid heat medium. In the second flow path 121, in the process of the heat medium flowing from the inlet side where the gaseous heat medium flows in toward the outlet side where the liquid heat medium flows out, the flow of the heat medium gradually branches and heats up. The cross-sectional area of the channel element 131 through which the medium flows gradually decreases. The larger the cross-sectional area of the flow path near the inlet through which the gaseous heat medium flows, the easier it is to reduce pressure loss. The smaller the cross-sectional area of the flow path near the outlet through which the liquid heat medium flows, the easier it is to suppress a decrease in the flow velocity of the heat medium. Therefore, in the heat exchanger 100, the flow path element 131 through which the heat medium flows is cut off so that a suitable flow rate of the heat medium is realized according to the phase change (density change) of the heat medium flowing through the second flow path 121. A second flow path 121 whose area gradually decreases is formed.

Therefore, in the heat exchanger 100 of the present embodiment, pressure loss is suppressed from increasing in the flow path near the inlet through which the gaseous fluid flows, and therefore the performance of the heat exchanger is suppressed from deteriorating. Furthermore, in the heat exchanger 100 of the present embodiment, the flow velocity of the fluid is prevented from decreasing in the flow path near the outlet through which the liquid fluid flows, so that the heat transfer efficiency is prevented from decreasing.

(3-2)
In the heat exchanger 100 of the present embodiment, in the second flow path 121, the heat medium flows from the inlet side where the gaseous heat medium flows in toward the outlet side where the liquid heat medium flows out. The flow gradually branches, and the number of channel elements 131 through which the heat medium flows gradually increases.

Therefore, in the heat exchanger 100 of the present embodiment, even if the cross-sectional area of the flow path through which the fluid flows from the inlet side to the outlet side gradually decreases, this contributes to the decrease in the flow rate of the fluid and the heat exchange of the fluid. Since the reduction in area (heat transfer area) of the portion where the heat transfer occurs is suppressed, a decrease in heat transfer efficiency is suppressed.

(4) Modification example (4-1) Modification example A
Next, specific examples of the second flow path 121 of the above embodiment will be described in Modifications A to D. 7-8 are plan views of the second heat transfer plate 120 similar to FIG. 6.

In FIG. 7, the distance L0 is the distance in the longitudinal direction DL between the second communication hole 120b on the upper side and the second communication hole 120b on the lower side. The position of the second communication hole 120b is the center of the circular shape of the second communication hole 120b. The distance L0 is a distance between the first heat transfer plate 110 and the second heat transfer plate 120, in which the heat medium flowing in from the upper second circulation hole 120b and flowing out from the lower second circulation hole 120b moves. This is the distance in the longitudinal direction DL. The distance L1 is the distance in the longitudinal direction DL between the boundary B1 between the first flow path area F1 and the second flow path area F2 and the upper second communication hole 120b.

In the above embodiment, it is preferable that the distance L0 and the distance L1 satisfy the relational expression 0.2×L0≦L1≦0.8×L0. In this case, in the longitudinal direction DL, the position where the flow of the heat medium first branches is at a position of 20% to 80% of the distance L0 corresponding to the length of the flow path of the heat medium. The position where the flow of the heat medium first branches corresponds to the position in the longitudinal direction DL of the boundary B1.

(4-2) Modification B
In FIG. 8, the distance L0 is the distance in the longitudinal direction DL between the second communication hole 120b on the upper side and the second communication hole 120b on the lower side. The position of the second communication hole 120b is the center of the circular shape of the second communication hole 120b. The distance L0 is a distance between the first heat transfer plate 110 and the second heat transfer plate 120, in which the heat medium flowing in from the upper second circulation hole 120b and flowing out from the lower second circulation hole 120b moves. This is the distance in the longitudinal direction DL. The distance L2 is the distance in the longitudinal direction DL between the boundary of two flow path regions adjacent in the longitudinal direction DL and the upper second communication hole 120b.

FIG. 8 shows boundaries B1 to B4 between two flow path regions adjacent in the longitudinal direction DL from the upper second flow hole 120b toward the lower second flow hole 120b. The number of boundaries is one less than the number of channel regions. FIG. 8 shows five flow path regions F1 to F5 and four boundaries B1 to B4. In the longitudinal direction DL, boundaries B1 to B4 are located at positions where the flow of the heat medium branches. In FIG. 8, the distance L2 is shown as the distance in the longitudinal direction DL between the boundary B2 and the upper second communication hole 120b.

In the above embodiment, it is preferable that the distance L0 and the distance L2 satisfy the relational expression 0.2×L0≦L2≦0.8×L0. In this case, in the longitudinal direction DL, the positions where the heat medium flow branches are all located at 20% to 80% of the distance L0 corresponding to the length of the heat medium flow path. The position where the flow of the heat medium branches corresponds to the position in the longitudinal direction DL of the boundaries B1 to B4.

(4-3) Modification C
In the above embodiment, the length in the longitudinal direction DL of each flow path region F1 to F5 is preferably 10% to 50% of the distance L0. The distance L0 is the distance in the longitudinal direction DL between the second communication hole 120b on the upper side and the second communication hole 120b on the lower side. The position of the second communication hole 120b is the center of the circular shape of the second communication hole 120b. The distance L0 is a distance between the first heat transfer plate 110 and the second heat transfer plate 120, in which the heat medium flowing in from the upper second circulation hole 120b and flowing out from the lower second circulation hole 120b moves. This is the distance in the longitudinal direction DL.

In this case, the distance from one branch position to the next branch position in the longitudinal direction DL is preferably 10% to 50% of the distance L0 corresponding to the length of the heat medium flow path. The branch position is a position in the longitudinal direction DL where the flow of the heat medium branches.

Note that in Modifications A to C, the distance L0 may be the dimension of the first heat transfer plate 110 and the second heat transfer plate 120 in the longitudinal direction DL. Further, the distance L0 may be a dimension of the second flow path 121 in the longitudinal direction DL.

(4-4) Modification D
In the above embodiment, when the value k is an integer satisfying 1≦k≦N-1, the number of channels in the k+1th channel region is equal to 2 times the number of channels in the k-th channel region. Preferably, it is 4 times to 4 times. In other words, each time the heat medium flow branches at the boundary between two adjacent flow path regions in the longitudinal direction DL, the number of heat medium flow paths increases by two to four times.

(4-5) Modification E
In the embodiment described above, the flow path regions F1 to F5 of the second flow path 121 have one or more flow path elements 131. The flow path element 131 corresponds to a space where the first rear surface 110sb of the first heat transfer plate 110 and the second front surface 120sa of the second heat transfer plate 120 face each other. In other words, in the channel element 131, the first heat transfer plate 110 is not in contact with the second heat transfer plate 120. However, in the channel element 131, a reinforcing element for bringing the first heat transfer plate 110 and the second heat transfer plate 120 into contact with each other is provided on at least one of the first heat transfer plate 110 and the second heat transfer plate 120. Good too. The reinforcing element is a component for ensuring the strength in the channel element 131 of the first heat transfer plate 110 and the second heat transfer plate 120. By providing the reinforcing element, the first rear surface 110sb of the first heat transfer plate 110 and the second front surface 120sa of the second heat transfer plate 120 come into contact with each other in the flow path element 131, thereby improving the flow path of the second flow path 121. A reduction in cross-sectional area is suppressed.

The reinforcing element is, for example, a point-like protrusion formed on at least one of the first heat transfer plate 110 and the second heat transfer plate 120. The reinforcing element has a size that does not reduce the flow velocity of the heat medium in the flow path element 131, and has a shape that does not substantially branch the flow path in the flow path element 131. In other words, the reinforcing elements preferably have dimensions and shapes that do not influence the number and cross-sectional area of the channel elements 131 of the channel region.

(4-6) Modification example F
In the embodiment described above, the heat exchanger 100 is formed so that the refrigerant flowing through the first flow path 111 and the heat medium flowing through the second flow path 121 flow in parallel. However, the heat exchanger 100 may be formed such that the refrigerant flowing through the first flow path 111 and the refrigerant flowing through the second flow path 121 flow in opposite directions. For example, in the first flow path 111, the refrigerant flows from the lower first flow hole 110b toward the upper first flow hole 110b, and in the second flow path 121, the heat medium flows through the upper second flow hole 110b. It may flow from 120b toward the second flow hole 120b on the lower side.

(4-7) Modification example G
In the embodiment described above, the heat exchanger 100 has a branching structure in which the flow of the heat medium gradually branches in the second flow path 121, and the number of flow path elements 131 through which the heat medium flows gradually increases. However, the heat exchanger 100 may have a branch structure similar to the second flow path 121 in the first flow path 111. Specifically, the first flow path 111 may have a branch structure in which the flow of the refrigerant gradually branches and the number of spaces (corresponding to the flow path elements 131) through which the refrigerant flows gradually increases.

Furthermore, in the heat source side heat exchanger 12 of the heat source side cycle 10, the flow path through which the refrigerant flows may have a branch structure similar to the second flow path 121. Further, in the usage-side heat exchanger 22 of the usage-side cycle 20, the flow path through which the heat medium flows may have a branch structure similar to the second flow path 121.

(4-8) Modification H
In the embodiment described above, R1234ze was exemplified as the refrigerant and carbon dioxide was exemplified as the heat medium, but the refrigerant and the heat medium are not limited thereto.

As the refrigerant, R32, HFO refrigerant, mixed refrigerant of R32 and HFO refrigerant, carbon dioxide, ammonia, propane, etc. may be used. As the heat medium, R-32, an HFO refrigerant, a mixed refrigerant of HFC-32 and HFO refrigerant, refrigerants such as carbon dioxide, ammonia, and propane, water, and antifreeze may be used.

(4-9) Modification I
In the embodiment described above, the first introduction pipe 150a, the first outlet pipe 150b, the second introduction pipe 160a, and the second outlet pipe 160b are all formed in the first frame 130. However, at least a portion of the first inlet pipe 150a, the first outlet pipe 150b, the second inlet pipe 160a, and the second outlet pipe 160b may be formed in the second frame 140.

(4-10) Modification J
In the embodiment described above, the refrigerant cycle device 1 is a binary refrigeration device having a heat source side cycle 10 and a usage side cycle 20. However, the refrigerant cycle device 1 may be a refrigeration device having only one vapor compression cycle for circulating refrigerant. For example, the refrigerant cycle device 1 includes a refrigerant cycle that includes elements corresponding to a heat source side compressor 11, a heat source side heat exchanger 12, a heat source side expansion valve 13, and a usage side heat exchanger 22. Good too. In this case, the heat source side heat exchanger 12 that functions as a refrigerant condenser may have a branch structure similar to the second flow path 121 of the above embodiment.

Although the embodiments of the present disclosure have been described above, it will be understood that various changes in form and details can be made without departing from the spirit and scope of the present disclosure as described in the claims. .

1: Refrigerant cycle device 100: Heat exchanger 110: First heat transfer plate (member)
120: Second heat transfer plate (member)
120b: Upper second communication hole (first opening)
120b: Lower second communication hole (second opening)
131: Channel element (channel)
DL: Longitudinal direction (first direction)
DS: Lamination direction (second direction)
F1: First flow path area F2: Second flow path area F5: Fifth flow path area (Nth flow path area)

Japanese Patent Application Publication No. 2016-90157

Claims

A heat exchanger in which a fluid flows in a first direction (DL) between a first opening (120b) and a second opening (120b),
Members (110 , 120),
Each of the N flow path regions has a flow path (131) through which the fluid flows,
The number of channels and the cross-sectional area of the first channel region (F1) located first from the first opening side in the first direction among the N channel regions are different from the number and cross-sectional area of the channels of the Nth channel region (F5) located Nth from the first opening side in the first direction among the channel regions;
Heat exchanger (100).
The number of channels in the i-th channel region located i-th from the first opening side in the first direction among the N channel regions is less than the number of channels in the j-th channel region located at the j-th (i, j are integers satisfying 1≦i<j≦N) from the first opening side in the first direction; ,
The cross-sectional area of the flow path in the i-th flow path region is larger than the cross-sectional area of the flow path in the j-th flow path region.
The heat exchanger according to claim 1.
The number of channels in the first channel region is 1,
The heat exchanger according to claim 1 or 2.
A boundary between a second flow path area (F2) located second from the first opening side in the first direction among the N flow path areas and the first flow path area; The distance L1 in the first direction between the first opening and the second opening, and the distance L0 in the first direction between the first opening and the second opening are as follows:
Satisfies the relational expression 0.2×L0≦L1≦0.8×L0,
The heat exchanger according to claim 3.
A distance L2 in the first direction between the first opening and a boundary between two adjacent flow path areas in the first direction among the N flow path areas, and a distance L2 between the first opening and the first opening. The distance L0 in the first direction between the two openings is
Satisfies the relational expression 0.2×L0≦L2≦0.8×L0,
The heat exchanger according to claim 4.
A k-th flow path region located at the k-th (k is an integer satisfying 1≦k≦N-1) from the first opening side in the first direction among the N flow path regions. The flow path branches at the boundary between the flow path area and the k+1st flow path area located at the k+1th position from the first opening side in the first direction among the N flow path areas,
The number of channels in the k+1 channel region is twice to four times the number of channels in the k-th channel region.
A heat exchanger according to any one of claims 1 to 5.
The length of each of the N flow path regions in the first direction is 10% to 50% of the distance in the first direction between the first opening and the second opening,
A heat exchanger according to any one of claims 1 to 6.
comprising a plurality of the members stacked in a second direction (DS) intersecting the first direction,
the N flow path regions are formed between the members adjacent in the second direction;
A heat exchanger according to any one of claims 1 to 7.
The N flow path areas having the flow paths through which the first medium that is the fluid flows and the N flow path areas having the flow paths through which the second medium that is the fluid flows are arranged in the second direction. layered alternately,
The first medium flows through the flow path from the first opening toward the second opening,
The second medium flows through the flow path from the second opening toward the first opening.
The heat exchanger according to claim 8.
A heat exchanger according to any one of claims 1 to 9 is provided.
Refrigerant cycle device (1).