WO2019216183A1

WO2019216183A1 - Laminated plate type heat exchanger

Info

Publication number: WO2019216183A1
Application number: PCT/JP2019/017067
Authority: WO
Inventors: 智史二田; 功玉田
Original assignee: 株式会社デンソー
Priority date: 2018-05-11
Filing date: 2019-04-22
Publication date: 2019-11-14

Abstract

A heat exchanger (10) has a heat exchange unit (HU) constituted by a plurality of laminated plate members (20). The heat exchanger has a tank space (T11) and a throttle part (222). The tank space is formed so as to extend in the plate lamination direction, is in communication with a plurality of first flow paths (W1), and distributes, to the plurality of first flow paths, a refrigerant flowing in from an inflow section (82) and comprising a two-phase state of a gas phase and a liquid phase. The throttle part partially reduces the cross-sectional area of the tank space in a direction orthogonal to the plate lamination direction.

Description

Plate stack heat exchanger

Cross-reference of related applications

This application is based on Japanese Patent Application No. 2018-092480 filed on May 11, 2018 and Japanese Patent Application No. 2019-079353 filed on April 18, 2019. Claims the benefit of that priority, the entire contents of which are incorporated herein by reference.

This disclosure relates to a plate stack type heat exchanger.

Conventionally, as this type of heat exchanger, there is a heat exchanger described in Patent Document 1. The heat exchanger described in Patent Document 1 has a structure in which a plurality of plate members are stacked and arranged with a predetermined gap therebetween. Offset fins are arranged in the gaps between adjacent plate members. A gap between adjacent plate members constitutes a coolant channel through which a coolant flows and a cooling water channel through which cooling water flows. The refrigerant channel and the cooling water channel are alternately arranged in the stacking direction of the plate members.

Among the plurality of plate members, a first outermost plate member disposed on one end side in the stacking direction is provided with a first joint that constitutes a cooling water inlet and a first cooling water pipe that constitutes a cooling water outlet. ing. Among the plurality of plate members, a second outermost plate member disposed on the other end side in the stacking direction is provided with a second joint that constitutes a refrigerant outlet and a second cooling water pipe that constitutes a cooling water inlet. ing. The plurality of plate-like members include a cooling water tank space that distributes the cooling water flowing from the first joint to the plurality of cooling water flow paths, and a refrigerant for distributing the refrigerant flowing from the second joint to the plurality of refrigerant flow paths. A tank space is formed.

Japanese Patent Laid-Open No. 2015-59669

In the heat exchanger described in Patent Document 1, when the refrigerant flowing into the heat exchanger is in a liquid phase and gas phase two phases, the liquid phase refrigerant flowing into the refrigerant tank space from the second joint has its inertia. Thus, after colliding with the inner wall surface at the end of the refrigerant tank space and turning back, the refrigerant flows toward the second joint. Therefore, the flow rate of the liquid phase refrigerant distributed to the refrigerant flow path from the inlet portion near the second joint in the refrigerant tank space, and the flow rate of the liquid phase refrigerant distributed to the refrigerant flow path from the end of the refrigerant tank space are as follows. The flow rate of the liquid-phase refrigerant distributed from the other intermediate portion of the refrigerant tank space to the refrigerant flow path is larger. Such a deviation in the flow rate of the liquid-phase refrigerant distributed to the plurality of refrigerant channels tends to occur particularly in a plate-stacked heat exchanger having a short length in the stacking direction. When the flow rate of the refrigerant distributed from the refrigerant tank space to the plurality of refrigerant flow paths is uneven, the heat exchange amounts of the plurality of refrigerant flow paths and the plurality of cooling water flow paths also vary. This is not preferable because it causes a decrease in the heat exchange performance of the heat exchanger.

An object of the present disclosure is to provide a plate stack type heat exchanger capable of improving heat exchange performance.

A plate stacking type heat exchanger according to an aspect of the present disclosure includes a heat exchanging unit including a plurality of plate members that are stacked and arranged with a gap therebetween, and a plurality of refrigerant flows between the plurality of plate members. The first flow path and a plurality of second flow paths through which a predetermined fluid flows are formed, and heat exchange is performed between the refrigerant flowing through the first flow path and the second flow path and the predetermined fluid. The heat exchange part has a tank space and a throttle part. The tank space is formed so as to extend in the plate stacking direction when the direction in which the plurality of plate members are stacked and arranged is the plate stacking direction, communicates with the plurality of first flow paths, and flows from the inflow portion. A refrigerant having a two-phase state of a gas phase and a liquid phase is distributed to the plurality of first flow paths. The throttle part partially reduces the cross-sectional area of the tank space in the direction orthogonal to the plate stacking direction.

According to this configuration, a part of the liquid-phase refrigerant that has flowed into the tank space from the inflow portion is blocked by the throttle portion, so that the liquid-phase refrigerant that flows into the first flow path disposed on the inflow portion side near the throttle portion. The flow rate increases. That is, it is possible to increase the flow rate of the liquid-phase refrigerant flowing into the first flow path located near the middle of the tank space. Thereby, since the deviation of the flow distribution of the liquid phase refrigerant distributed from the tank space to the plurality of first flow paths can be suppressed, the heat exchange performance can be improved.

FIG. 1 is a front view showing a front structure of a plate-stacked heat exchanger according to the first embodiment. FIG. 2 is a plan view showing a planar structure of the plate stack type heat exchanger according to the first embodiment. FIG. 3 is an exploded view showing an exploded structure of the plate stacking type heat exchanger according to the first embodiment. FIG. 4 is a cross-sectional view showing a cross-sectional structure taken along line IV-IV in FIG. FIG. 5 is a cross-sectional view showing a cross-sectional structure around the aperture portion of the first embodiment. FIG. 6 is a cross-sectional view showing a cross-sectional structure of a plate stacking type heat exchanger according to a first modification of the first embodiment. FIG. 7 is a cross-sectional view showing a cross-sectional structure of a plate-stacked heat exchanger according to a first modification of the first embodiment. FIG. 8 is a cross-sectional view showing a cross-sectional structure of a plate stack type heat exchanger according to a second modification of the first embodiment. FIG. 9 is a graph showing the relationship between the number of stages of cooling water flow paths and the cooling ratio in a plate-stacked heat exchanger not provided with a throttle. FIG. 10 is a graph showing the relationship between the number of stages of the cooling water flow path and the cooling ratio in the plate stack type heat exchanger of the second embodiment. FIG. 11 is a cross-sectional view showing a cross-sectional structure of a plate-stacked heat exchanger according to another embodiment.

Hereinafter, an embodiment of a plate stacked heat exchanger will be described with reference to the drawings. In order to facilitate the understanding of the description, the same constituent elements in the drawings will be denoted by the same reference numerals as much as possible, and redundant description will be omitted.
<First Embodiment>
First, the plate lamination type heat exchanger according to the first embodiment will be described. A heat exchanger 10 shown in FIG. 1 cools cooling water by exchanging heat between, for example, cooling water for cooling a storage battery mounted on a vehicle and a refrigerant having a temperature lower than that of the cooling water. Used as equipment. In this case, the cooling water corresponds to a predetermined fluid having a temperature higher than that of the refrigerant.

1, the heat exchanger 10 includes a heat exchange unit HU in which a plurality of plate members 20 are stacked in the Z-axis direction. That is, in the present embodiment, the Z-axis direction corresponds to the plate stacking direction. Hereinafter, one direction of the Z-axis direction is referred to as “Z1 direction”, and the opposite direction is referred to as “Z2 direction”.

In each plate member 20, as indicated by the one-dot chain line and the two-dot chain line, a refrigerant flow path W1 through which the refrigerant flows and a cooling water flow path W2 through which the cooling water flows are formed. Thereby, inside the heat exchanger 10, the some refrigerant | coolant flow path W1 and the some cooling water flow path W2 are arrange | positioned alternately. In the present embodiment, the refrigerant flow path W1 corresponds to the first flow path, and the cooling water flow path W2 corresponds to the second flow path.

As shown in FIG. 2, the heat exchanger 10 has a substantially rectangular cross-sectional shape perpendicular to the Z-axis direction. Hereinafter, the longitudinal direction and the short direction of the heat exchanger 10 are referred to as “X-axis direction” and “Y-axis direction”, respectively. One direction of the X-axis direction is referred to as “X1 direction”, and the opposite direction is referred to as “X2 direction”.

A first refrigerant tank space T11 and a second refrigerant tank space T12 are formed inside the two corners of the four corners of the heat exchanger 10 so as to extend in the Z-axis direction. Yes. In addition, a first cooling water tank space T21 and a second cooling water tank space T22 are formed in the remaining two corners located on the diagonal line so as to extend in the Z-axis direction.

At the end of the upper surface of the heat exchanger 10 on the X2 direction side, there are a refrigerant inflow portion 82 communicated with the first refrigerant tank space T11 and a cooling water outflow portion 83 communicated with the first cooling water tank space T21. Is provided. As shown in FIG. 1, at the end of the bottom surface of the heat exchanger 10 on the X1 axis direction side, a refrigerant outflow part 80 communicated with the second refrigerant tank space T12 and a second cooling water tank space T22 communicated. The cooling water inflow portion 81 is provided.

In the heat exchanger 10, a refrigerant having a two-phase state of a gas phase and a liquid phase flows in from the refrigerant inflow portion 82, and cooling water flows in from the cooling water inflow portion 81. As indicated by a one-dot chain line in FIG. 1, the refrigerant that has flowed into the first refrigerant tank space T 11 from the refrigerant inflow portion 82 is distributed to a plurality of refrigerant flow paths W 1 inside the heat exchanger 10. The refrigerant that has flowed through the plurality of refrigerant flow paths W1 is collected in the second refrigerant tank space T12 and then flows out of the refrigerant outflow portion 80. Further, as indicated by a two-dot chain line in FIG. 1, the cooling water that has flowed into the second cooling water tank space T22 from the cooling water inflow portion 81 is distributed to the plurality of cooling water flow paths W2 inside the heat exchanger 10. The The cooling water that has flowed through the plurality of cooling water flow paths W2 is collected in the first cooling water tank space T21 and then flows out from the cooling water outflow portion 83. In the heat exchanger 10, the cooling water is cooled by heat exchange between the refrigerant flowing through the refrigerant flow path W1 and the cooling water flowing through the cooling water flow path W2.

Next, a specific structure of the heat exchanger 10 will be described. As shown in FIG. 3, the heat exchanger 10 includes a plate member 20, a refrigerant fin 30, a cooling water fin 40, a first outermost shell plate 50, and a second outermost shell plate 60. I have. These members are made of a metal material such as aluminum.

The plate member 20 includes an outer plate 21 and an inner plate 22.
The outer plate 21 is made of a plate-like member having a cross-sectional shape orthogonal to the Z-axis direction formed in a substantially rectangular shape. On the outer peripheral edge portion of the outer plate 21, an overhang portion 210 protruding in the Z1 direction is formed. The plurality of outer plates 21 are arranged so that the tip portions of the respective overhanging portions 210 face the Z1 direction, and are stacked as shown in FIG. The overhang portions 210 of the plurality of outer plates 21 are joined to each other by brazing.

As shown in FIG. 4, a protrusion 212 that protrudes in a cylindrical shape in the Z2 direction is formed at a position corresponding to the first refrigerant tank space T11 in the outer plate 21 with an axis m1 parallel to the Z-axis direction as a center. ing. The internal space of the protrusion 212 is a through hole 211 that penetrates the outer plate 21 in the Z-axis direction along the axis m1.

The inner plate 22 is made of a plate-like member having a cross-sectional shape orthogonal to the Z-axis direction formed in a substantially rectangular shape. As shown in FIG. 3, the inner plate 22 is disposed in a gap between the

outer plates

21 and 21 adjacent in the Z-axis direction. The inner plate 22 is joined to the

outer plates

21 and 21 adjacent in the Z-axis direction by brazing. As shown in FIG. 4, the inner plate 22 divides a space formed between adjacent

outer plates

21 and 21 into independent refrigerant flow paths W1 and cooling water flow paths W2 that are not communicated with each other. Yes.

As shown in FIG. 4, the inner plate 22 is formed with a protruding portion 221 that protrudes in a cylindrical shape in the Z1 direction about the axis m1 at a portion corresponding to the through hole 211 of the outer plate 21. The protrusion 221 is formed with a burring hole 220 that penetrates the outer plate 21 in the Z-axis direction along the axis m1. The burring hole 220 is formed when burring the first refrigerant tank space T11 in the heat exchanger 10. The outer peripheral surface of the protrusion 221 is joined to the inner peripheral surface of the through hole 211 of the outer plate 21 by brazing. The first refrigerant tank space T11 is configured by connecting the through holes 211 of the plurality of inner plates 22 in the Z-axis direction by such a joining structure. That is, the first refrigerant tank space T11 is formed so as to extend along the axis m1. In the heat exchanger 10 of the present embodiment, the length L of the first refrigerant tank space T11 is set to 110 mm or less.

The first refrigerant tank space T11 is communicated with a plurality of refrigerant flow paths W1 through an inlet P formed between the inner plate 22 and the outer plate 21. The first refrigerant tank space T11 and the cooling water flow path W2 are partitioned by the joint structure of the protrusion 212 of the outer plate 21 and the protrusion 221 of the inner plate 22, so that the first refrigerant tank space T11 and the cooling water flow path W2 Communication is blocked. That is, the first refrigerant tank space T11 communicates only with the plurality of refrigerant flow paths W1.

Of the protrusions 221 formed on the plurality of inner plates 22, the first refrigerant tank orthogonal to the Z-axis direction is provided at the protrusion 221 disposed at a position shifted in the Z2 direction from the intermediate position in the Z-axis direction. The narrowed portion 222 is formed so as to partially narrow the cross-sectional area of the space T11.

Specifically, in the burring hole 220 of the inner plate 22 where the narrowed portion 222 is not formed, the portion corresponding to the tip of the protruding portion 221 is the narrowest. That is, the minimum value of the cross-sectional area of the burring hole 220 orthogonal to the Z-axis direction is “S1” shown in FIG. This cross-sectional area S1 corresponds to the minimum value of the cross-sectional area of the first refrigerant tank space T11 in the portion excluding the throttle portion 222. On the other hand, the cross-sectional area S2 of the flow hole 222a of the throttle part 222 orthogonal to the Z-axis direction is smaller than the minimum value S1 of the cross-sectional area of the first refrigerant tank space T11.

In addition, the throttle part 222 is not formed in the second refrigerant tank space T12, the first cooling water tank space T21, and the second cooling water tank space T22. The second refrigerant tank space T12, the first cooling water tank space T21, and the second cooling water tank space T22 have a similar structure to the first refrigerant tank space T11 except that the throttle portion 222 is not formed. Therefore, a detailed description of their structure is omitted.

As shown in FIG. 3, the refrigerant fins 30 are respectively disposed in a plurality of refrigerant flow paths W 1 formed between the outer plate 21 and the inner plate 22. The cooling water fins 40 are respectively disposed in a plurality of cooling water flow paths W 2 formed between the outer plate 21 and the inner plate 22. As the refrigerant fin 30 and the cooling water fin 40, for example, corrugated fins formed in a wave shape can be used. The refrigerant fin 30 and the cooling water fin 40 have a function of improving the heat exchange performance of the heat exchanger 10 by increasing the heat transfer area.

As shown in FIG. 3, the first outermost shell plate 50 is fixed to the inner plate 22 disposed at the extreme end in the Z1 direction by brazing. As shown in FIG. 2, the first outermost shell plate 50 is provided with a refrigerant inflow portion 82 and a cooling water outflow portion 83. The first outermost shell plate 50 closes one end of the second refrigerant tank space T12 in the Z1 direction and one end of the second coolant tank space T22 in the Z1 direction. As shown in FIG. 4, the cross-sectional area S3 of the refrigerant inflow portion 82 orthogonal to the Z-axis direction is smaller than the minimum value S1 of the cross-sectional area of the first refrigerant tank space T11.

As shown in FIG. 3, the second outermost shell plate 60 is fixed to the outer plate 21 disposed at the endmost portion in the Z2 direction by brazing. The second outermost shell plate 60 is assembled with the refrigerant outflow portion 80 and the cooling water inflow portion 81 shown in FIG. The second outermost shell plate 60 closes one end portion in the Z2 direction of the first refrigerant tank space T11 and one end portion in the Z1 direction of the first cooling water tank space T21.

Next, an operation example of the heat exchanger 10 of the present embodiment will be described.
As shown in FIG. 4, in the heat exchanger 10, a refrigerant having a liquid phase and a gas phase two-phase state flows from the refrigerant inflow portion 82 into the first refrigerant tank space T 11. When the liquid-phase refrigerant flows into the first refrigerant tank space T11 from the refrigerant inflow portion 82, the flow path cross-sectional area increases. Therefore, the liquid phase refrigerant becomes a jet and flows into the first refrigerant tank space T11. At this time, as indicated by an arrow F 1 in FIG. 4, a part of the liquid-phase refrigerant that has been jetted collides with the throttle portion 222, thereby blocking the flow of some liquid-phase refrigerant. Thereby, liquid phase refrigerant flows in into refrigerant channel W1 through a plurality of inflow parts P1 arranged in the Z1 direction side rather than throttling part 222 among a plurality of inflow ports P arranged near throttle part 222. Therefore, it is possible to increase the flow rate of the liquid-phase refrigerant flowing from the inflow portion P1 into the refrigerant flow path W1.

Further, as indicated by an arrow F 2 in FIG. 4, a part of the liquid-phase refrigerant that has become a jet flows through the flow hole 222 a of the throttle portion 222. The liquid phase refrigerant flows so as to be folded back in the Z1 direction by reaching the end of the first refrigerant tank space T11 in the Z2 direction due to inertia and colliding with the second outermost shell plate 60. The liquid-phase refrigerant that has flowed so as to be folded back reaches the throttle portion 222 and is blocked. Thereby, liquid phase refrigerant flows into refrigerant channel W1 through a plurality of inflow parts P2 arranged in the Z2 direction side rather than throttling part 222 among a plurality of inflow ports P arranged near the restricting part 222. Therefore, it is possible to increase the flow rate of the liquid phase refrigerant flowing from the inflow portion P2 into the refrigerant flow path W1.

According to the plate stack type heat exchanger 10 of the present embodiment described above, the operations and effects shown in the following (1) to (7) can be obtained.
(1) Since the flow rate of the liquid-phase refrigerant flowing into the refrigerant flow path W1 located near the middle of the first refrigerant tank space T11 can be increased, the refrigerant flow located near the end of the first refrigerant tank space T11 It is possible to balance the flow rate of the liquid phase refrigerant flowing into the path W1 and the flow rate of the liquid phase refrigerant flowing into the refrigerant flow path W1 located near the middle of the first refrigerant tank space T11. That is, since it is possible to suppress an uneven flow distribution of the liquid-phase refrigerant distributed from the first refrigerant tank space T11 to the plurality of refrigerant flow paths W1, it is possible to improve heat exchange performance.

(2) The length L of the first refrigerant tank space T11 in the Z-axis direction is set to 110 mm or less. In the heat exchanger 10 having such a structure, a part of the liquid-phase refrigerant that has flowed into the first refrigerant tank space T11 from the refrigerant inflow portion 82 easily collides with the second outermost shell plate 60. However, the flow rate variations in the plurality of refrigerant flow paths W1 are likely to occur. Therefore, it is effective to adopt the structure of the heat exchanger 10 of this embodiment.

(3) The flow direction of the refrigerant flowing into the first refrigerant tank space T11 from the refrigerant inflow portion 82 is parallel to the axis m1, that is, parallel to the extending direction of the first refrigerant tank space T11. In the heat exchanger 10 having such a structure, a part of the liquid-phase refrigerant that has flowed into the first refrigerant tank space T11 from the refrigerant inflow portion 82 easily collides with the second outermost shell plate 60. However, the flow rate variations in the plurality of refrigerant flow paths W1 are likely to occur. Therefore, it is effective to adopt the structure of the heat exchanger 10 of this embodiment.

(4) The cross-sectional area S2 of the throttle part 222 orthogonal to the Z-axis direction is based on the minimum value S1 of the cross-sectional area of the portion excluding the throttle part 222 in the cross-sectional area of the first refrigerant tank space T11 orthogonal to the Z-axis direction. Is also small. As a result, a part of the liquid-phase refrigerant that has flowed into the first refrigerant tank space T11 from the refrigerant inflow portion 82 collides with the throttle portion 222 more reliably. Further, the liquid refrigerant flowing so as to be folded back in the Z1 direction by colliding with the second outermost shell plate 60 also collides with the throttle portion 222 more reliably. Therefore, since the flow rate of the liquid phase refrigerant flowing into the refrigerant flow path W1 located near the middle of the first refrigerant tank space T11 can be increased more reliably, the liquid phase refrigerant distributed to the plurality of refrigerant flow paths W1. It is possible to more accurately suppress the deviation of the flow rate distribution.

(5) Only one throttle 222 is provided in the first refrigerant tank space T11. Thereby, compared with the case where the some aperture | diaphragm | squeeze part 222 is provided, manufacturing cost can be reduced.
(6) The diaphragm 222 is formed integrally with the plate member 20. Thereby, the throttle part 222 can be provided in the first refrigerant tank space T11 without increasing the number of parts.

(7) As shown in FIG. 4, the first refrigerant tank space T11 and the refrigerant inflow portion 82 are disposed on the same axis m1, and have a cross-sectional shape of the first refrigerant tank space T11 orthogonal to the Z-axis direction. The position of the center of gravity coincides with the position of the center of gravity of the cross-sectional shape of the refrigerant inflow portion 82 orthogonal to the Z-axis direction. In the heat exchanger 10 having such a structure, a part of the liquid-phase refrigerant that has flowed into the first refrigerant tank space T11 from the refrigerant inflow portion 82 easily collides with the second outermost shell plate 60. However, the flow rate variations in the plurality of refrigerant flow paths W1 are likely to occur. Therefore, it is effective to adopt the structure of the heat exchanger 10 of this embodiment.

(First modification)
Next, the 1st modification of the heat exchanger 10 of 1st Embodiment is demonstrated.
As shown in FIG. 6, in the heat exchanger 10 of the present modification, a plurality of constricted portions 222 are provided in the first refrigerant tank space T11. According to such a configuration, the flow rate of the liquid-phase refrigerant flowing into the refrigerant flow path W1 located in the vicinity of the middle of the first refrigerant tank space T11 can be more reliably increased. It is possible to more reliably suppress the deviation in the flow rate distribution of the distributed liquid phase refrigerant.

Further, when a plurality of throttle parts 222 are provided in the first refrigerant tank space T11, the cross-sectional area of the flow holes 222a of the throttle parts 222 may be changed. Thereby, for example, it is possible to balance the flow rate of the refrigerant flowing in the Z2 direction through the flow hole 222a of the throttle unit 222 and the flow rate of the refrigerant flowing in the Z1 direction by colliding with the throttle unit 222. It is.

For example, in the heat exchanger 10 shown in FIG. 7, throttle portions 222 (1) to 222 (3) are provided in the first refrigerant tank space T11 in order from the vicinity of the refrigerant inflow portion 82. The cross-sectional areas S21 to S23 of the flow holes 222a of the narrowed portions 222 (1) to 222 (3) have a relationship of “S21> S22> S23”. According to such a configuration, most of the refrigerant that flows into the first refrigerant tank space T11 from the refrigerant inflow portion 82 and reaches the throttle portion 222 (1) does not collide with the throttle portion 222 (1). It flows downstream through the flow hole 222a. Thereby, a refrigerant | coolant can be appropriately distributed to the refrigerant | coolant flow path W1 arrange | positioned downstream from the throttle part 222 (1).

In addition, when the flow rate of the refrigerant flowing from the refrigerant inflow portion 82 into the first refrigerant tank space T11 is large, the refrigerant may flow from the refrigerant inflow portion 82 into the first refrigerant tank space T11 in the form of a jet. In such a case, the cross-sectional areas S21 to S23 of the flow holes 222a of the throttle portions 222 (1) to 222 (3) are in a relationship of “S21 <S22 <S23” according to the spread of the jet of refrigerant. You may set as follows. According to such a configuration, when the refrigerant flows into the first refrigerant tank space T11 from the refrigerant inflow portion 82 in the form of a jet, the refrigerant distribution in each refrigerant flow path W1 can be improved.

As described above, if the cross-sectional areas S21 to S23 of the flow holes 222a of the throttle portions 222 (1) to 222 (3) are appropriately changed in accordance with the structure of the heat exchanger 10, the refrigerant flow in each refrigerant flow path W1 is changed. Since the distribution can be improved, as a result, the heat exchange performance of the heat exchanger 10 can be improved.

(Second modification)
Next, the 2nd modification of the heat exchanger 10 of 1st Embodiment is demonstrated.
As shown in FIG. 8, in the heat exchanger 10 of the present modification, a protrusion 213 that protrudes in a direction orthogonal to the Z-axis direction is formed in a portion corresponding to the first refrigerant tank space T11 in the outer plate 21. Is formed. Similarly, a protruding portion 223 that protrudes in a direction orthogonal to the Z-axis direction is formed in a portion corresponding to the first refrigerant tank space T11 in the inner plate 22. The Z1 direction surface 213a of the protrusion 213 of the outer plate 21 faces the Z2 direction surface 223a of the protrusion 223 of the inner plate 22. The mating surface 213a of the outer plate 21 and the mating surface 223a of the inner plate 22 are joined by brazing. A first refrigerant tank space T11 is configured by through

holes

214 and 224 formed so as to penetrate the mating surface 213a of the outer plate 21 and the mating surface 223a of the inner plate 22, respectively.

Of the plurality of inner plates 22, at least one inner plate 22 is formed with a throttle portion 225 so as to partially narrow the cross-sectional area of the first refrigerant tank space T11 orthogonal to the Z-axis direction.
Specifically, in the cross-sectional area of the first refrigerant tank space T11 orthogonal to the Z-axis direction, the portion corresponding to the tip portions of the protruding

portions

213 and 223 of the

plates

21 and 22 is the narrowest in the portion excluding the throttle portion 225. It has become. That is, of the cross-sectional area of the first refrigerant tank space T11 orthogonal to the Z direction, the minimum value of the cross-sectional area of the portion excluding the throttle portion 225 is “S1” shown in FIG. On the other hand, the cross-sectional area S2 of the hole 225a of the throttle portion 225 orthogonal to the Z-axis direction is smaller than the minimum value S1 of the cross-sectional area of the first refrigerant tank space T11.

Even with such a configuration, it is possible to obtain the same or similar actions and effects as those of the heat exchanger 10 of the first embodiment.
In addition, in the heat exchanger 10 of this modification, although illustrated about the structure which forms the expansion part 225 in the protrusion part 223 of the inner plate 22, the expansion part 225 may be formed in the protrusion part 213 of the outer plate 21. FIG. . Further, the narrowed portion 225 may be formed on both the protruding portion 213 of the outer plate 21 and the protruding portion 223 of the inner plate 22.

Second Embodiment
Next, a second embodiment of the heat exchanger 10 will be described.
The inventors of the present invention have a conventional heat exchanger that is not provided with a throttle portion, and the flow rate of the refrigerant flowing through the refrigerant flow path disposed near the central portion of the refrigerant tank space is likely to be smaller than other portions. Have been confirmed through experiments and simulations. From the results of experiments, simulations, and the like, it is preferable to arrange the throttle portion near the center of the refrigerant tank space in consideration of the refrigerant distribution in each refrigerant flow path. Hereinafter, a preferable arrangement of the throttle part will be described in detail.

In the model of the heat exchanger shown in FIG. 9 in which the throttle part is not provided, the inventors have provided between the adjacent refrigerant flow paths W1 and W1 when the refrigerant is introduced from the refrigerant inflow part 82. The cooling degree of the cooling water flowing through the cooling water flow path is measured. The measurement results are as shown in the bar graph shown in FIG. The horizontal axis of the bar graph indicates the number of stages of the cooling water flow paths sequentially attached from the cooling water flow path closest to the refrigerant inflow portion 82. Specifically, numbers from “1” to “14” are assigned as the number of steps in order from the cooling water flow path closest to the refrigerant inflow portion 82. The vertical axis of the bar graph indicates the ratio of the cooling degree in each cooling water flow channel to the average value when the average cooling water cooling value in each cooling water flow channel is “1”. For example, a cooling water passage having a cooling ratio exceeding “1” means that the cooling water passage is easier to cool than the average. Conversely, a cooling water channel having a cooling ratio of less than “1” means that the cooling water channel is more difficult to cool than average.

As shown in the graph of FIG. 9, the cooling ratio of the cooling water flow paths having the number of stages “6” to “13” is less than “1”. In the cooling water flow path having a cooling ratio of less than “1”, it is assumed that the cooling water is more difficult to cool than the average because the flow rate of the refrigerant flowing through the adjacent refrigerant flow path W1 is small. For example, in the cooling water flow path having the number of stages “10”, it is considered that the flow rate of the refrigerant flowing through the refrigerant flow paths W1d and W1e adjacent thereto is small. If the flow rate of the refrigerant in the refrigerant flow path can be increased, it is possible to efficiently improve the refrigerant distribution in the heat exchanger 10. Specifically, it is considered that increasing the refrigerant flow rate in the refrigerant flow paths W1a to W1g corresponding to the cooling water flow paths having the number of stages “6” to “13” is effective in improving the refrigerant distribution.

FIG. 10 shows, as an example, the cooling ratio of each cooling water flow path when the throttle portion 222 is provided at a position corresponding to the cooling water flow path having the number of stages “10”. As shown in FIG. 10, when the throttle portion 222 is provided, not only the flow rate of the refrigerant in the refrigerant channels W1d and W1e adjacent to the cooling water channel having the number of stages “10”, but also other refrigerant channels W1a It has been confirmed that the flow rates of the refrigerants W1c, W1f, and W1g also increase.

Based on the results of the above experiments and simulations, the inventors set the length of the refrigerant tank space T11 in the plate stacking direction Z to “L” and the refrigerant tank in the plate stacking direction Z as shown in FIG. When the position of the space T11 from the refrigerant inflow portion 82 is “x”, the distribution of the refrigerant in the heat exchanger 10 can be improved by forming the throttle portion 222 at a position that satisfies the following expression f1. And has gained knowledge.

0.37 × L ≦ x ≦ 0.85 × L (f1)
According to the plate lamination type heat exchanger 10 of this embodiment described above, the operation and effect shown in the following (8) can be obtained.
(8) The heat exchanger 10 is provided with the throttle 222 so as to satisfy the above formula f1. According to such a configuration, the refrigerant distribution in each refrigerant flow path W1 can be improved, and as a result, the heat exchange performance of the heat exchanger 10 can be further improved.

<Other embodiments>
In addition, each embodiment can also be implemented with the following forms.
The throttle unit 222 may be configured by a component separate from the plate member 20. For example, as shown in FIG. 11, the narrowed portion 222 may be formed on a member 23 separate from the plate member 20, and the member 23 may be joined to the inner surface of the burring hole 220 by brazing or the like.

The refrigerant outflow part 80, the cooling water inflow part 81, the refrigerant inflow part 82, and the cooling water outflow part 83 may all be provided on the upper surface of the heat exchanger 10. Alternatively, all of the refrigerant outflow portion 80, the cooling water inflow portion 81, the refrigerant inflow portion 82, and the cooling water outflow portion 83 may be provided on the bottom surface of the heat exchanger 10.

-The two types of fluids used for heat exchange in the heat exchanger 10 are not limited to cooling water for cooling the storage battery and refrigerant for cooling the cooling water, but may be any one of hot water and low-temperature refrigerant, etc. Two types of fluids can be used.
-The heat exchanger 10 of each embodiment can be used for arbitrary heat exchange systems. For example, the heat exchanger 10 of each embodiment is a heat exchange system that cools cooling water for cooling a battery, a motor generator, an inverter, a substrate, and the like using a refrigerant having a temperature lower than that of the cooling water in the heat pump system. It can be used as a container. The heat pump system in which the heat exchanger is used may be a system that uses the exhaust heat of the battery or the like recovered by the heat exchanger for heating the interior of the vehicle through a water-cooled condenser or a heater core. It may be a system that radiates heat to the outside air.

・ This disclosure is not limited to the above specific examples. Any of the above specific examples that are appropriately modified by those skilled in the art are also included in the scope of the present disclosure as long as they have the features of the present disclosure. Each element included in each of the specific examples described above, and the arrangement, conditions, shape, and the like thereof are not limited to those illustrated, and can be appropriately changed. Each element included in each of the specific examples described above can be appropriately combined as long as no technical contradiction occurs.

Claims

A plurality of first flow paths (W1) having a heat exchanging portion (HU) composed of a plurality of plate members (20) arranged in a stack with gaps, and in which a refrigerant flows between the plurality of plate members. And a plurality of second flow paths (W2) through which a predetermined fluid flows, and heat exchange is performed between the refrigerant flowing through the first flow path and the second flow path and the predetermined fluid, respectively. A plate stacked heat exchanger (10),
When a direction in which a plurality of the plate members are stacked is a plate stacking direction,
The heat exchange part is
The refrigerant is formed so as to extend in the plate stacking direction, communicates with the plurality of first flow paths, and includes the refrigerant composed of a two-phase state of a gas phase and a liquid phase flowing in from the inflow portion (82). Tank space (T11) distributed to one flow path;
A plate stacking type heat exchanger comprising: throttle portions (222, 225) that partially reduce a cross-sectional area of the tank space in a direction orthogonal to the plate stacking direction.
The plate stacking type heat exchanger according to claim 1, wherein a length of the tank space in the plate stacking direction is set to 110 mm or less.
The plate stacking type heat exchanger according to claim 1 or 2, wherein a flow direction of the refrigerant flowing into the tank space from the inflow portion is parallel to a direction in which the tank space extends.
Burring holes (220) are respectively formed in the plurality of plate members so as to penetrate in the plate stacking direction,
The tank space is configured by communicating the burring holes of each of the plurality of plate members,
The cross-sectional area of the throttle portion orthogonal to the plate stacking direction is smaller than the minimum value of the cross-sectional area of the portion excluding the throttle portion of the cross-sectional area of the tank space orthogonal to the plate stacking direction. 4. The plate-stacked heat exchanger according to claim 3.
The tank space is constituted by a through hole formed so as to penetrate the mating surfaces (213a, 223a) of the adjacent plate members,
The cross-sectional area of the throttle portion orthogonal to the plate stacking direction is smaller than the minimum value of the cross-sectional area of the portion excluding the throttle portion of the cross-sectional area of the tank space orthogonal to the plate stacking direction. 4. The plate-stacked heat exchanger according to claim 3.
The plate-stacked heat exchanger according to any one of claims 1 to 5, wherein only one throttle part is provided in the tank space.
The plate-stacked heat exchanger according to any one of claims 1 to 5, wherein a plurality of the throttle portions are provided in the tank space.
The plate stacked heat exchanger according to any one of claims 1 to 7, wherein the throttle portion is formed integrally with the plate member.
The position of the center of gravity of the cross-sectional shape of the tank space orthogonal to the plate stacking direction and the position of the center of gravity of the cross-sectional shape of the inflow portion orthogonal to the plate stacking direction coincide with each other. The plate stacked heat exchanger according to one item.
The plate stacked heat exchanger according to any one of claims 1 to 9, wherein a fluid having a temperature higher than that of the refrigerant is used as the predetermined fluid.
When the length of the tank space in the plate stacking direction is L, and the position of the tank space from the inflow portion in the plate stacking direction is x, the following expression 0.37 × L ≦ x ≦ 0.85 × L
The heat exchanger according to any one of claims 1 to 10, wherein the throttle portion is disposed at a position x that satisfies the following conditions.