JP2016191540A - Heat exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress retention of supercooled fluid in a heat exchange section and thus improve condensation performance when making the heat exchange section function as a condenser.SOLUTION: An outdoor heat exchanger 100 includes: a heat exchange section 10; an air blowing fan; a refrigerant header 40 to which each of one end sides of a plurality of refrigerant flow passages 11, 12, 13, 14 is connected at a first connection position C1; a plurality of capillary tubes 21, 22, 23, 24 connected to the other end sides of the plurality of refrigerant flow passages 11, 12, 13, 14 at second connection positions C2, respectively; an a distributor 50. A flowing direction of air blown by the air blowing fan has a speed component toward a vertical upper side, and each of the plurality of second connection positions C2 is disposed at a position equal to a position P2 that is a half of the overall height H of the heat exchange section 10 or below the position P2 in the vertical direction.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a heat exchanger.

2. Description of the Related Art Conventionally, a heat exchanger is known in which a plurality of mutually independent refrigerant channels are arranged in multiple stages in the vertical direction, and one end side of each of the plurality of refrigerant channels is connected to a refrigerant distributor through a capillary tube. (For example, refer to Patent Document 1).
In Patent Document 1, when the heat exchanger functions as a condenser, in order to prevent liquid refrigerant from accumulating in the lowermost refrigerant flow path and excessively increasing the degree of supercooling, the lowermost refrigerant flow is disclosed. It is disclosed that the height from the lower end of the path to the upper end of the lowermost capillary tube is adjusted.

Japanese Patent No. 3985831

  In Patent Document 1, the connection positions of the plurality of refrigerant flow paths and the capillary tubes connected thereto are positions at regular intervals in the entire area of the total height in the vertical direction of the heat exchanger. Therefore, the distance in the vertical direction between the connection position between the uppermost refrigerant flow path and the capillary tube and the connection position between the lowermost refrigerant flow path and the capillary tube is substantially the same as the overall height of the heat exchanger.

  Therefore, the difference between the pressure due to the self-weight of the liquid refrigerant from the connection position of the uppermost refrigerant flow path to the refrigerant flow divider and the pressure due to the self-weight of the liquid refrigerant from the connection position of the lowermost refrigerant flow path to the refrigerant flow divider is large. As a result, the liquid refrigerant from the plurality of capillary tubes is merged and equalized by the refrigerant flow divider, and the equalized pressure increases, and accordingly, the liquid refrigerant is not easily discharged from the lowermost refrigerant flow path to the capillary tube. It stays inside the road.

  The present invention has been made in view of such circumstances, and in a heat exchanger including a heat exchanging portion that circulates a refrigerant through a plurality of refrigerant passages arranged along the vertical direction, the heat exchanging portion is provided. When it functions as a condenser, it aims at suppressing condensation of a supercooled liquid in a heat exchange part, and improving condensation performance.

In order to solve the above-described problems, the present invention employs the following means.
A heat exchanger according to an aspect of the present invention includes a heat exchange unit that circulates a refrigerant through a plurality of refrigerant flow paths arranged along a vertical direction and performs heat exchange with air, and the air exchanged with the air A refrigerant fan that circulates the gas, a refrigerant in a gas phase, and a refrigerant collecting pipe that is connected to one end of each of the plurality of refrigerant channels at a first connection position, respectively, and a second end of each of the plurality of refrigerant channels. A plurality of refrigerant distribution pipes connected at a second connection position; and a refrigerant distributor for merging the plurality of refrigerant distribution pipes at a merging position, wherein a flow direction of the air blown by the blower fan is the vertical direction And each of the plurality of second connection positions is the same as or below the position that is ½ of the total height of the heat exchange section in the vertical direction. Has been placed.

  According to the heat exchanger according to one aspect of the present invention, when the heat exchange unit functions as a condenser, the supercooled liquid condensed in the heat exchange unit has a plurality of refrigerant distribution pipes at each of the plurality of second connection positions. And are merged at the merge position by the refrigerant distributor. Since the pressure of the supercooled liquid merged at the merge position is equalized, if the equalized pressure is too high, the supercooled liquid is discharged from the second connection position located below in the vertical direction to the refrigerant distribution pipe. The supercooled liquid stays inside.

According to the heat exchanger according to one aspect of the present invention, each of the plurality of second connection positions is arranged at the same position as or lower than the position that is ½ of the total height of the heat exchange section in the vertical direction. ing.
Therefore, the vertical distance between the second connection position located at the top in the vertical direction and the second connection position located at the bottom in the vertical direction among the plurality of second connection positions is the total height of the heat exchange unit. Same or shorter than 1/2.
As a result, as compared with the case where this distance is set to be approximately equal to the total height of the heat exchange section, the pressure due to the self-weight of the supercooled liquid from the second connection position located at the top in the vertical direction to the merge position and the maximum in the vertical direction. The difference with the pressure by the dead weight of the supercooling liquid from the 2nd connection position located in the lower part to a joining position can be made small enough, and the residence in the heat exchange part of a supercooling liquid can be suppressed.

  Moreover, according to the heat exchanger concerning 1 aspect of this invention, while a ventilation fan distribute | circulates air toward the back surface along a perpendicular direction from the front surface along the perpendicular direction of a heat exchange part, it is ventilated by a ventilation fan. The air flow direction has a velocity component directed upward in the vertical direction. Therefore, in the heat exchange unit, the change in the wind speed due to the vertical position is large in the upper half of the vertical direction, but the change in the wind speed due to the vertical position is suppressed in the lower half of the vertical direction.

  Therefore, in the lower half of the heat exchange part where the refrigerant is condensed from the two-phase flow of the gas phase and the liquid phase to the supercooled liquid, the bias of the heat exchange efficiency of each of the plurality of refrigerant channels is suppressed. As a result, the heat exchange efficiency of each of the plurality of refrigerant flow paths is biased, and the amount of supercooled liquid remaining in each of the plurality of refrigerant flow paths changes, and accordingly, the pressure difference due to the weight of the supercooled liquid at the merging position is changed. The increase is suppressed.

  Thus, according to the heat exchanger according to one aspect of the present invention, in the heat exchanger that includes the heat exchange unit that causes the refrigerant to flow through the plurality of refrigerant channels arranged along the vertical direction, the heat exchange unit includes: When functioning as a condenser, it is possible to improve the condensation performance by suppressing the supercooled liquid from staying in the heat exchange section.

In the heat exchanger according to one aspect of the present invention, each of the plurality of first connection positions is the same as or higher than a position that is 1/3 of the total height of the heat exchange unit in the vertical direction. It may be what has been done.
By doing in this way, compared with the case where the 1st connection position located in the lowest part is made to correspond with the lower end of the vertical direction of a heat exchange part, the height of the perpendicular direction from the 1st connection position located in the lowest part to a merge position is high. It is possible to sufficiently secure the thickness and promote the circulation of the supercooled liquid from the first connection position to the joining position.

In the heat exchanger according to one aspect of the present invention, at least one of the plurality of refrigerant channels branches into a plurality of branch channels at a branch position, and each of the plurality of branch channels is the The configuration connected to the refrigerant collecting pipe may be used.
With the above configuration, it is possible to reduce the number of refrigerant distribution pipes that the refrigerant flow divider joins with respect to the number of refrigerant flow paths and branch flow paths connected to the refrigerant collecting pipe. Since the number of second connection positions decreases, the vertical distance between the second connection position located at the top and the second connection position located at the bottom is shortened, and the pressure difference due to the self-weight of the supercooled liquid is reduced. It can be made sufficiently small.

In the heat exchanger configured as described above, the following conditional expression may be satisfied.
L2 / 10 ≦ L1 ≦ L2 / 2 (1)
here,
L1: a flow path length of the refrigerant flow path from the first connection position to the branch position;
L2: A flow path length of the refrigerant flow path from the first connection position to the second connection position.

  By doing in this way, the branch position on the refrigerant flow path branched into the plurality of branch flow paths can be the same as the intermediate position of the flow path length L2 of the refrigerant flow path or the first connection position side. . Thus, when the heat exchange unit functions as an evaporator, the position where the void ratio (ratio of the gas phase to the total volume of the two phases of the gas phase and the liquid phase) becomes a branch position, and the second connection position It is possible to suppress the occurrence of a bias in the amount of refrigerant flowing into each branch flow path as compared with the case where the side is set as a branch position.

  Further, the branch position on the refrigerant flow path branched into the plurality of branch flow paths can be set to a position separated from the first connection position by 1/10 of the flow path length L2 or further away therefrom. Thereby, the pressure loss of the refrigerant flow path can be suppressed to a certain level, and the circulation of the refrigerant can be promoted.

In the heat exchanger according to one aspect of the present invention, the joining position may be a position below a lower end of the heat exchange unit in the vertical direction.
By doing in this way, a merge position can be made further lower than the 2nd connection position located in the lowest part, and distribution of supercooling liquid from a plurality of 2nd connection positions to the merge position can be promoted.

  According to the present invention, in a heat exchanger including a heat exchange unit that circulates a refrigerant through a plurality of refrigerant channels arranged along the vertical direction, when the heat exchange unit functions as a condenser, the supercooling liquid is It is possible to improve the condensation performance by suppressing the retention in the heat exchange section.

It is a system configuration figure of a heat exchange system. It is a longitudinal cross-sectional view which shows an outdoor heat exchanger. It is a figure which shows the refrigerant | coolant system | strain of an outdoor heat exchanger. It is a figure which shows the refrigerant | coolant system | strain of the outdoor heat exchanger of a comparative example. It is a figure which shows the relationship between the position on the refrigerant system of an outdoor heat exchanger, and the pressure of a refrigerant | coolant. It is a figure which shows the relationship between the position on the refrigerant system of the outdoor heat exchanger of a comparative example, and the pressure of a refrigerant | coolant. It is a figure which shows the relationship between the height of the perpendicular direction of a heat exchange part, and a wind speed ratio. It is a figure which shows the modification of the refrigerant | coolant system | strain of an outdoor heat exchanger.

Below, the heat exchange system 1 concerning one Embodiment of this invention is demonstrated with reference to drawings.
The heat exchange system 1 of this embodiment is a system in which an outdoor heat exchanger 100 (heat exchanger) and an indoor heat exchanger 200 are connected by a refrigerant system to circulate the refrigerant.
An example of the heat exchange system 1 is an air conditioning system in which one or more indoor heat exchangers are connected to one outdoor heat exchanger. Another example of the heat exchange system is a heat pump hot water supply system using a CO ₂ refrigerant.

As shown in the system configuration diagram of FIG. 1, the heat exchange system 1 includes an outdoor heat exchanger 100, an indoor heat exchanger 200, a compressor 210 that compresses a refrigerant, and a liquid component contained in a high-temperature and high-pressure refrigerant gas. It is the system | strain provided with the accumulator 220 which removes, the four-way valve 230, and the expansion valve 240, and connected these with refrigerant | coolant piping.
The heat exchanging system 1 shown in FIG. 1 can selectively execute a cooling operation for cooling the room and a heating operation for heating the room by switching the circulation direction of the refrigerant by the four-way valve 230.

  When performing the heating operation, the four-way valve 230 guides the refrigerant compressed by the compressor 210 to the indoor heat exchanger 200 to cause the indoor heat exchanger 200 to function as a condenser (condenser), and is adiabatically expanded by the expansion valve 240. The direction of circulation of the refrigerant is set so as to guide the refrigerant to the outdoor heat exchanger 100 to function as an evaporator (evaporator) (direction indicated by a solid arrow in FIG. 1).

  On the other hand, when performing the cooling operation, the four-way valve 230 guides the refrigerant compressed by the compressor 210 to the outdoor heat exchanger 100 so that the outdoor heat exchanger 100 functions as a condenser (condenser), and the expansion valve 240 insulates the air. The circulation direction of the refrigerant is set so that the expanded refrigerant is guided to the indoor heat exchanger 200 to function as an evaporator (evaporator) (direction indicated by a broken arrow in FIG. 1).

As shown in the longitudinal sectional view of FIG. 2, in the outdoor heat exchanger 100 of the present embodiment, the heat exchange unit 10 and the blower fan 30 are arranged inside an exterior 100 a whose longitudinal section is formed in a vertically long rectangular shape. Device.
The exterior 100a is a box-shaped housing that is formed in a rectangular shape in plan view and installed on the installation surface S. A suction port 100b and a suction port 100c are formed on the side surface of the exterior 100a, and air is introduced into the interior from the outside of the exterior 100a. Further, a discharge port 100d is formed on the upper surface of the exterior 100a so that air that has passed through the heat exchanging unit 10 is discharged from the inside of the exterior 100a to the outside.

As shown by an arrow in FIG. 2, the blower fan 30 is a device that blows air so as to discharge the air inside the exterior 100 a upward in the vertical direction.
The blower fan 30 circulates air inside the exterior 100a from the front surface 10a of the heat exchange unit 10 that is a surface along the vertical direction toward the back surface 10b of the heat exchange unit 10 that is a surface along the vertical direction.

As shown by arrows in FIG. 2, the suction ports 100b and 100c formed on the side surface of the exterior 100a introduce air into the exterior 100a from the side of the exterior 100a.
The air introduced into the exterior 100a along the horizontal direction parallel to the installation surface S from the suction ports 100b and 100c gradually changes from the horizontal direction to the vertically upward direction, and from the discharge port 100d to the vertical direction. Will be discharged along.
Therefore, as shown by an arrow in FIG. 2, the flow direction of the air that is blown by the blower fan 30 and passes through the heat exchanging unit 10 has a velocity component directed upward in the vertical direction.

Next, the refrigerant system of the outdoor heat exchanger 100 will be described with reference to FIG.
FIG. 3 is a side view of the outdoor heat exchanger 100 shown in FIG. 2, and the exterior 100a is omitted. The vertical direction in FIG. 3 matches the vertical direction with reference to the installation surface S in FIG.
As shown in FIG. 3, the outdoor heat exchanger 100 includes a heat exchange unit 10, a refrigerant distribution pipe 20, a refrigerant header 40 (refrigerant collecting pipe), and a distributor 50 (refrigerant distributor).

The heat exchanging unit 10 is a device that exchanges heat with air blown by the blower fan 30 by circulating the refrigerant through the plurality of refrigerant flow paths 11, 12, 13, and 14 arranged along the vertical direction.
The refrigerant flow paths 11, 12, 13, and 14 are tube-shaped members formed of a metal member such as copper, and a flow path through which the refrigerant flows is formed.

  For example, the heat exchange unit 10 has the plurality of refrigerant flow paths 11, 12, 13, and 14 inserted into insertion holes of a plurality of aluminum plate-like fins (not shown) that are continuously arranged in the horizontal direction. It can be configured as a fin-and-tube heat exchanger.

The refrigerant header 40 is a pipe through which a gas-phase refrigerant flows and one end sides of the plurality of refrigerant flow paths 11, 12, 13, and 14 are connected at the first connection position C1.
When the outdoor heat exchanger 100 functions as a condenser (condenser), the refrigerant header 40 supplies gas-phase refrigerant to the plurality of refrigerant flow paths 11, 12, 13, and 14. On the other hand, when the outdoor heat exchanger 100 functions as an evaporator (evaporator), gas phase refrigerant is supplied to the refrigerant header 40 from the plurality of refrigerant flow paths 11, 12, 13, and 14.

The refrigerant distribution pipe 20 includes capillary tubes 21, 22, 23, and 24 that are connected to the other end sides of the plurality of refrigerant flow paths 11, 12, 13, and 14 at the second connection position C2, respectively.
The distributor 50 is a device that joins the capillary tubes 21, 22, 23, and 24 at the joining position C3. The merge position C3 is disposed at a position below the lower end of the heat exchange unit 10 in the vertical direction (vertical direction in FIG. 3) orthogonal to the installation surface S of the outdoor heat exchanger 100.

When the outdoor heat exchanger 100 functions as a condenser (condenser), the supercooled liquid discharged from the second connection position C2 of the plurality of refrigerant flow paths 11, 12, 13, 14 is capillary tubes 21, 22, 23, 24 and is led to the merging position C3 of the distributor 50.
On the other hand, when the outdoor heat exchanger 100 functions as an evaporator (evaporator), the supercooled liquid discharged from the junction position C3 of the distributor 50 is guided to each of the capillary tubes 21, 22, 23, and 24, and a plurality of refrigerants It is supplied to the second connection position C2 of the flow paths 11, 12, 13, and 14.

As shown in FIG. 3, in the vertical direction (vertical direction in FIG. 3) perpendicular to the installation surface S of the outdoor heat exchanger 100, each of the plurality of first connection positions C <b> 1 is 1 of the total height H of the heat exchange unit 10. It arrange | positions rather than the position P1 used as / 3.
Here, the heat exchange part 10 means the distance from the lower end to the upper end of the heat exchange part 10 in the vertical direction, as shown in FIG.

  As shown in FIG. 3, the first connection position C1 at which the refrigerant flow path 14 and the refrigerant header 40 are connected is located at the lowest position in the vertical direction, but this position is above the position P1. Similarly, the first connection position C1 where the refrigerant flow path 13 and the refrigerant header 40 are connected, the first connection position C1 where the refrigerant flow path 12 and the refrigerant header 40 are connected, and the refrigerant flow path 11 and the refrigerant header 40. Is connected to the first connection position C1 above the position P1.

  In FIG. 3, the first connection position C1 where the refrigerant flow path 14 and the refrigerant header 40 are connected is disposed above the position P1, but the refrigerant flow path 14 and the refrigerant header 40 are The lowermost first connection position C1 to be connected may coincide with the position P1.

  Further, as shown in FIG. 3, in the vertical direction (vertical direction in FIG. 3), each of the plurality of second connection positions C <b> 2 is below the position P <b> 2 that is ½ of the total height H of the heat exchange unit 10. Is arranged.

  As shown in FIG. 3, the second connection position C2 where the refrigerant flow path 11 and the capillary tube 21 are connected is located at the uppermost part in the vertical direction, but this position is below the position P2. Similarly, the second connection position C2 where the refrigerant flow path 12 and the capillary tube 22 are connected, the second connection position C2 where the refrigerant flow path 13 and the capillary tube 23 are connected, and the refrigerant flow path 14 and the capillary tube 24. The second connection position C2 to which is connected is lower than the position P2.

  In FIG. 3, the second connection position C2 where the refrigerant flow path 11 and the capillary tube 21 are connected is disposed below the position P2. However, the refrigerant flow path 11 and the capillary tube 21 are connected to each other. The uppermost second connection position C2 to be connected may coincide with the position P1.

Next, the relationship between the position of the outdoor heat exchanger 100 of the present embodiment on the refrigerant system and the pressure of the refrigerant will be described in comparison with the outdoor heat exchanger 100 ′ of the comparative example.
FIG. 4 is a diagram showing a refrigerant system of the outdoor heat exchanger 100 ′ of the comparative example.
As shown in FIG. 4, in the outdoor heat exchanger 100 ′ of the comparative example, the refrigerant flow paths 11 ′, 12 ′, 13 ′, and 14 ′ and the refrigerant header 40 ′ are connected at the first connection position C1 ′. .
As shown in FIG. 4, the first connection position C1 ′ located at the lowermost part is disposed below the position P1 that is 1/3 of the total height H of the heat exchange unit 10 ′.

As shown in FIG. 4, the outdoor heat exchanger 100 ′ of the comparative example includes a refrigerant flow path 11 ′, 12 ′, 13 ′, 14 ′ and a refrigerant distribution pipe 20 ′ (capillary tubes 21 ′, 22 ′, 23). ', 24') are connected at the second connection position C2 '.
As shown in FIG. 4, the second connection position C2 ′ located at the top is arranged above the position P2 that is ½ of the total height H of the heat exchange unit 10 ′.

FIG. 5 is a diagram showing the relationship between the position of the outdoor heat exchanger 100 on the refrigerant system and the pressure of the refrigerant. Here, the refrigerant system refers to a system including the refrigerant header 40, the refrigerant flow paths 11, 12, 13, 14 and the refrigerant distribution pipe 20 shown in FIG.
In FIG. 5, the refrigerant system including the refrigerant flow path 11 and the capillary tube 21 is the first system, the system including the refrigerant flow path 12 and the capillary tube 22 is the second system, the refrigerant flow path 13 and the capillary tube 23. A system including the refrigerant system 14 is referred to as a third system, and a system including the refrigerant flow path 14 and the capillary tube 24 is referred to as a fourth system.

As shown in FIG. 5, since the first connection position C1 is connected to the refrigerant header 40, the refrigerant pressure at the first connection position C1 is the same pressure Pr1 in each of the first to fourth systems. .
Moreover, as shown in FIG. 5, since the merge position C3 is connected to the distributor 50, the refrigerant pressure at the merge position C3 is the same pressure Pr3 in each of the first to fourth systems.

In FIG. 5, the refrigerant pressure increases from the second connection position C2 toward the merge position C3 because the second connection position C2 is disposed above the merge position C3. This is because pressure due to the weight of the liquid) occurs.
In FIG. 5, although the pressure of the refrigerant increases from the second connection position C2 toward the merge position C3, the pressure Pr3 at the merge position C3 is lower than the pressure Pr1 at the first connection position C1.
Therefore, in each of the first to fourth systems of the outdoor heat exchanger 100 of the present embodiment, the refrigerant smoothly circulates without staying from the first connection position C1 to the joining position C3.

FIG. 6 is a diagram illustrating the relationship between the position of the outdoor heat exchanger 100 ′ of the comparative example on the refrigerant system and the pressure of the refrigerant. Here, the refrigerant system refers to a system comprising the refrigerant header 40 ', the refrigerant flow paths 11', 12 ', 13', 14 'and the refrigerant distribution pipe 20' shown in FIG.
In FIG. 6, the refrigerant system including the refrigerant flow path 11 ′ and the capillary tube 21 ′ is the first system, the system including the refrigerant flow path 12 ′ and the capillary tube 22 ′ is the second system, and the refrigerant flow path 13. A system including 'and the capillary tube 23' is referred to as a third system, and a system including the refrigerant flow path 14 'and the capillary tube 24' is referred to as a fourth system.

As shown in FIG. 6, since the first connection position C1 ′ is connected to the refrigerant header 40 ′, the refrigerant pressure at the first connection position C1 ′ is the same pressure Pr1 ′ in each of the first to fourth systems. It has become.
Further, as shown in FIG. 6, since the merge position C3 ′ is connected to the distributor 50, the refrigerant pressure at the merge position C3 ′ is the same pressure Pr3 ′ in each of the first to fourth systems. .

In FIG. 6, the refrigerant pressure increases from the second connection position C2 ′ toward the merge position C3 ′ because the second connection position C2 ′ is disposed above the merge position C3 ′. This is because pressure is generated due to the dead weight of the refrigerant (supercooled liquid).
In FIG. 6, the pressure of the refrigerant increases from the second connection position C2 ′ toward the merge position C3 ′, and the pressure Pr3 ′ at the merge position C3 ′ is higher than the pressure Pr1 ′ at the first connection position C1. It is high.

  Therefore, in each of the first to fourth systems of the outdoor heat exchanger 100 ′ of the comparative example, the refrigerant is likely to stay from the first connection position C <b> 1 ′ to the joining position C <b> 3 ′. In particular, in the fourth system arranged at the lowermost part, the refrigerant pressure Pr1 ′ at the first connection position C1 ′ is the refrigerant pressure in the entire region of the refrigerant system from the first connection position C1 ′ to the merge position C3 ′. Is over. For this reason, in the fourth system arranged at the lowermost part, the refrigerant stays in the entire region from the first connection position C1 'to the joining position C3'.

  Thus, in the outdoor heat exchanger 100 ′ of the comparative example, the stagnation of the refrigerant occurs because the second connection position C2 ′ disposed at the uppermost position compared to the outdoor heat exchanger 100 of the present embodiment. This is because the pressure is increased due to the weight of the refrigerant (supercooled liquid).

Next, the relationship between the vertical height of the heat exchange unit 10 and the wind speed ratio will be described with reference to FIG.
In FIG. 7, the horizontal axis indicates the vertical height of the heat exchanging unit 10, and the origin indicates the lower end of the heat exchanging unit 10 in the vertical direction. Moreover, in FIG. 7, the vertical axis | shaft has shown the wind speed ratio of the air ventilated by the ventilation fan 30 in the height of the vertical direction of the heat exchange part 10 shown on a horizontal axis. This wind speed ratio indicates the ratio when the average value of the wind speed at each position of the height in the vertical direction of the heat exchange unit 10 is 1.0.

As shown in FIG. 7, in the lower half of the heat exchanging unit 10 (the horizontal axis is in the range of H / 2 from the origin), the wind speed ratio converges in the range of 0.5 to 0.7 and has little fluctuation. On the other hand, in the upper half of the heat exchanging unit 10 (the horizontal axis is in the range of H / 2 to H), the wind speed ratio greatly fluctuates in the range of 0.7 to 2.0.
This is because the flow direction of the air blown by the blower fan 30 has a velocity component that is directed upward in the vertical direction, and it is easy to flow through the upper half of the heat exchange unit 10.

In the outdoor heat exchanger 100 having the wind speed ratio shown in FIG. 7, when the second connection position C2 is arranged in the upper half of the heat exchange unit 10 and the refrigerant is supplied to the joining position C3, the second connection position C2 is arranged in a region with a high wind speed ratio. In this case, the heat exchange efficiency is biased between the refrigerant flow path disposed in the region with the high wind speed ratio and the refrigerant flow path disposed in the region with the relatively low wind speed ratio. If it does so, the quantity of the supercooling liquid which retains in each of a plurality of refrigerant channels will change, and the difference of the pressure by the self-weight of supercooling liquid will become large in connection with it.
Therefore, in the outdoor heat exchanger 100 of the present embodiment, each of the plurality of second connection positions C2 is arranged in the lower half of the heat exchange unit 10.

The operation and effect of the heat exchange system 1 of the present embodiment described above will be described.
According to the outdoor heat exchanger 100 included in the heat exchange system 1 of the present embodiment, when the heat exchange unit 10 functions as a condenser, the supercooled liquid condensed in the heat exchange unit 10 has a plurality of second connection positions C2. Are respectively discharged to the capillary tubes 21, 22, 23, and 24, and are merged by the distributor 50 at the merge position C3. Since the pressure of the supercooled liquid merged at the merge position C3 is equalized, if this equalized pressure is too high, the supercooled liquid is transferred from the second connection position C2 positioned below in the vertical direction to the capillary tube 24. Becomes difficult to be discharged and the supercooled liquid stays inside.

According to the outdoor heat exchanger 100 of the present embodiment, each of the plurality of second connection positions C2 is the same as or lower than the position P2 that is ½ of the total height H of the heat exchange unit 10 in the vertical direction. Is arranged.
Therefore, the vertical distance between the second connection position C2 located at the top in the vertical direction and the second connection position C2 located at the bottom in the vertical direction among the plurality of second connection positions C2 is the heat exchange unit. It is equal to or shorter than 1/2 of the total height H of 10.

  Thereby, compared with the case where this distance is made to be about the same as the total height H of the heat exchange unit 10, the pressure due to the weight of the supercooled liquid from the second connection position C2 located at the uppermost part in the vertical direction to the joining position C2, and The difference between the pressure due to the self-weight of the supercooled liquid from the second connection position C2 located at the lowest position in the vertical direction to the merge position C3 is sufficiently reduced, and the retention of the supercooled liquid in the heat exchange unit 10 is suppressed. Can do.

  Moreover, according to the outdoor heat exchanger 100 of this embodiment, while the ventilation fan 30 distribute | circulates air toward the back surface 10b along the vertical direction from the front surface 10a along the vertical direction of the heat exchange part 10, a ventilation fan The flow direction of the air blown by 30 has a velocity component directed upward in the vertical direction. Therefore, in the heat exchanging unit 10, the change in the wind speed due to the vertical position is large in the upper half of the vertical direction, but the change in the wind speed due to the vertical position is suppressed in the lower half of the vertical direction.

  Therefore, in the lower half of the heat exchange unit 10 where the refrigerant is condensed from the two-phase flow of the gas phase and the liquid phase to the supercooled liquid, the bias of the heat exchange efficiency of each of the plurality of refrigerant channels is suppressed. As a result, the heat exchange efficiency of each of the plurality of refrigerant flow paths is biased, and the amount of supercooled liquid staying in each of the plurality of refrigerant flow paths changes, and accordingly, the pressure difference due to the weight of the supercooled liquid at the merging position C3. Is suppressed from increasing.

  Thus, according to the present embodiment, in the outdoor heat exchanger 100 including the heat exchange unit 10 that circulates the refrigerant through the plurality of refrigerant channels arranged along the vertical direction, the heat exchange unit 10 is used as a condenser. When making it function, it can suppress that a supercooled liquid retains in the heat exchange part 10, and can improve a condensation performance.

In the outdoor heat exchanger 100 of the present embodiment, each of the plurality of first connection positions C1 is the same as or higher than the position P1 that is 1/3 of the total height H of the heat exchange unit 10 in the vertical direction. Has been.
By doing in this way, compared with the case where the 1st connection position C1 located in the lowest part is made to correspond with the lower end of the perpendicular direction of the heat exchange part 10, the vertical from the 1st connection position C1 located in the lowest part to a merge position A sufficient height in the direction can be secured, and the circulation of the supercooling liquid from the first connection position C1 to the joining position C3 can be promoted.

[Other Embodiments]
In the above description, each of the plurality of refrigerant flow paths 11, 12, 13, 14 is connected to the refrigerant header 40 as it is, but other modes may be used.
For example, as shown in FIG. 8, the refrigerant flow paths 111 and 112 may be branched at the branch positions B <b> 1 and B <b> 2 of the heat exchange unit 110 and then connected to the refrigerant header 40.

The heat exchange unit 110 included in the outdoor heat exchanger 300 illustrated in FIG. 8 includes a refrigerant channel 111 and a refrigerant channel 112. One end side of the refrigerant flow path 111 is branched into a branch flow path 111a and a branch flow path 111b at a branch position B1 inside the heat exchange unit 110, and is connected to the refrigerant header 40 at a first connection position C1. Similarly, one end side of the refrigerant flow path 112 is branched into a branch flow path 112a and a branch flow path 112b at a branch position B2 inside the heat exchange unit 110, and is connected to the refrigerant header 40 at a first connection position C1. .
Here, both the refrigerant flow path 111 and the refrigerant flow path 112 are branched to the branch flow path at the branch position, but only one of the refrigerant flow path 111 and the refrigerant flow path 112 is branched at the branch position. You may make it branch on a road.

  By doing in this way, the number (two) of capillary tubes which the distributor 50 merges can be decreased with respect to the number (four) of the branch flow paths connected to the refrigerant header 40. Since the number of second connection positions C2 is reduced, the vertical distance between the second connection position C2 located at the top and the second connection position C2 located at the bottom is shortened, and the pressure due to the weight of the supercooled liquid Can be made sufficiently small.

  The other end side of the refrigerant flow path 111 is connected to the capillary tube 121 of the refrigerant distribution pipe 120 at the second connection position C2, and the other end side of the refrigerant flow path 112 is connected to the capillary of the refrigerant distribution pipe 120 at the second connection position C2. It is connected to the tube 122.

Here, in the outdoor heat exchanger 300 shown in FIG. 8, the following conditional expressions are satisfied.
L2 / 10 ≦ L1 ≦ L2 / 2 (1)
here,
L1: the flow path lengths of the refrigerant flow paths 111 and 112 from the first connection position C1 to the branch positions B1 and B2,
L2: The flow path length of the refrigerant flow paths 111 and 112 from the first connection position C1 to the second connection position C2.

  By doing in this way, branch position B1 and B2 on refrigerant flow paths 111 and 112 branched into a plurality of branch flow paths are equal to or more than the intermediate position of flow path length L2 of refrigerant flow paths 111 and 112. It can be on the first connection position C1 side. Thus, when the heat exchange unit 10 functions as an evaporator, the position where the void ratio (the ratio of the gas phase to the total volume of the two phases of the gas phase and the liquid phase) becomes the branch positions B1 and B2, Compared with the case where the second connection position C2 side is set to the branch positions B1 and B2, it is possible to suppress a deviation in the amount of refrigerant flowing into each branch flow path.

  The branch positions B1 and B2 on the refrigerant flow paths 111 and 112 branched into a plurality of branch flow paths are separated from the first connection position C1 by 1/10 of the flow path length L2 or further away from the position. can do. Thereby, the pressure loss of the refrigerant flow paths 111 and 112 can be suppressed to a certain level and the circulation of the refrigerant can be promoted.

DESCRIPTION OF SYMBOLS 1 Heat exchange system 10 Heat exchange part 10a Front surface 10b Back surface 11, 12, 13, 14 Refrigerant flow path 20 Refrigerant distribution piping 21, 22, 23, 24 Capillary tube 30 Blower fan 40 Refrigerant header (refrigerant collecting piping)
50 Distributor (refrigerant shunt)
100,300 Outdoor heat exchanger (heat exchanger)
200 Indoor Heat Exchanger 210 Compressor 220 Accumulator 230 Four-way Valve 240 Expansion Valve C1 First Connection Position C2 Second Connection Position C3 Junction Position S Installation Surface

Claims (5)

A heat exchanging unit that exchanges heat with air by circulating the refrigerant through a plurality of refrigerant channels arranged along the vertical direction;
A blower fan that circulates the air from the front surface along the vertical direction of the heat exchange unit toward the back surface along the vertical direction;
A refrigerant collecting pipe in which gas-phase refrigerant flows and one end side of each of the plurality of refrigerant flow paths is connected at a first connection position;
A plurality of refrigerant distribution pipes respectively connected to the other end side of the plurality of refrigerant flow paths at a second connection position;
A refrigerant distributor that merges the plurality of refrigerant distribution pipes at a merge position;
The flow direction of the air blown by the blower fan has a velocity component directed upward in the vertical direction,
Each of the plurality of second connection positions is a heat exchanger that is disposed at the same position as or lower than a position that is ½ of the total height of the heat exchange section in the vertical direction.   2. The heat exchanger according to claim 1, wherein each of the plurality of first connection positions is the same as or higher than a position that is 1/3 of the total height of the heat exchange unit in the vertical direction. . At least one of the plurality of refrigerant channels branches into a plurality of branch channels at a branch position;
The heat exchanger according to claim 1 or 2, wherein each of the plurality of branch channels is connected to the refrigerant collecting pipe. The heat exchanger according to claim 3 satisfying the following conditional expression.
L2 / 10 ≦ L1 ≦ L2 / 2 (1)
here,
L1: a flow path length of the refrigerant flow path from the first connection position to the branch position;
L2: A flow path length of the refrigerant flow path from the first connection position to the second connection position.   The heat exchanger according to any one of claims 1 to 4, wherein the joining position is a position below a lower end of the heat exchange unit in the vertical direction.

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