JP2018189352A - Heat exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To maintain high heat exchange efficiency in the entire refrigerant flow path by suppressing the drift of the gas-liquid two-phase fluid flowing into a plurality of heat exchange channels in a heat exchanger for heat exchange of the gas-liquid two-phase fluid. do. A heat exchanger according to an embodiment has a plurality of first plates forming a plurality of first flow paths through which a first fluid flows, and a plurality of first plates forming a plurality of second flow paths through which a second fluid flows. The first fluid is in a gas-liquid two-phase state in at least a part of the first flow path and comprises a plate structure composed of a second plate of the above and a plurality of laminated plates including the first. A first inlet header space communicating with a fluid supply portion and the plurality of first flow paths formed in each of the plurality of first plates, a first fluid discharge portion, and the plurality of first plates. A first outlet header space communicating with the plurality of first flow paths formed in each is formed in the plurality of first plates, and the first outlet header space includes the plurality of second plates. A space penetrating along the stacking direction of the plurality of plates is formed. [Selection diagram] Fig. 2

Description

  The present disclosure relates to a heat exchanger that exchanges heat between a gas-liquid two-phase fluid.

The NH ₃ is used as the primary refrigerant, _NH 3 / CO ₂ refrigeration using CO ₂ as a secondary refrigerant is vaporized and NH ₃ in the gas-liquid two-phase, thereby the heat exchanger for liquefying the CO ₂ vapor (CO ₂ A liquefier). Conventionally, shell-and-plate heat exchangers, plate-type heat exchangers, shell-and-tube heat exchangers, and the like are used for this type of liquefier.
In Patent Document 1, NH ₃ is used as a primary refrigerant, CO ₂ is used as a secondary refrigerant, and these flow paths are constituted by a large number of fine flow paths called so-called microchannels, thereby exchanging heat between the two media. A heat exchanger with improved performance is disclosed.

JP 2015-1114080 A

The micro-channel heat exchanger has a large number of fine flow paths to secure a heat transfer area and improve heat exchange performance.It can also handle high-pressure fluids, reducing the equipment size and reducing the amount of refrigerant. Make it possible.
However, in a heat exchanger in which a gas-liquid two-phase fluid is divided into a plurality of flow paths, the heat absorption performance is reduced in a flow path with a small liquid phase ratio. Therefore, it is important to take measures to suppress the uneven flow in which the flow rate and the gas-liquid ratio of the gas-liquid two-phase flow are evenly distributed among the plurality of channels.
Incidentally, in particular drift tends to occur when the gas-liquid density ratio is high NH ₃ is a gas-liquid two-phase flow.

  In one embodiment, in view of the above problems, in a heat exchanger including a gas-liquid two-phase fluid as a heat exchange fluid, the flow of the gas-liquid two-phase fluid flowing into the plurality of heat exchange channels is suppressed. The object is to maintain high heat exchange efficiency as a whole.

(1) A heat exchanger according to an embodiment
A heat exchanger for exchanging heat between the first fluid and the second fluid to vaporize the first fluid,
A plurality of stacked layers including a plurality of first plates forming a plurality of first flow paths through which the first fluid flows, and a plurality of second plates forming a plurality of second flow paths through which the second fluid flows. Comprising a plate structure composed of
The first fluid is in a gas-liquid two-phase state in at least a part of the first flow path;
A first inlet header space communicating with the first fluid supply section and the plurality of first flow paths formed in each of the plurality of first plates; the first fluid discharge section; A first outlet header space communicating with the plurality of first flow paths formed in each of the one plate is formed in the plurality of first plates;
The first outlet header space forms a space penetrating along the stacking direction of the plurality of plates including the plurality of second plates.

The pressure loss of the first fluid between the first inlet header space and the first outlet header space is the sum of the pressure losses of the respective first fluids in the first inlet header space, the first flow path, and the first outlet header space. It is.
According to the configuration of (1) above, since the first outlet header space forms a space penetrating along the stacking direction of the plurality of plates, the flow rate of the first outlet header space through which steam flows is reduced. Pressure loss can be reduced. As a result, the ratio of the pressure loss of the first fluid in the first flow path relatively increases.
Moreover, since the pressure loss in the first outlet header space is reduced, the difference in pressure loss at the outlet portions of the plurality of first flow paths is also reduced.
Thus, since the difference in pressure loss between the plurality of first flow paths can be reduced, the heat of the first fluid and the second fluid in some of the first flow paths caused by the drift of the first fluid between the first flow paths. A decrease in exchange performance can be suppressed. Thereby, the heat exchange efficiency can be maintained high as the entire first flow path.

(2) In one embodiment, in the configuration of (1),
The first inlet header space is divided by the plurality of second plates along the stacking direction of the plurality of plates.
According to the configuration of (2) above, the first inlet header space is divided along the plate stacking direction by the plurality of second plates, thereby reducing the volume of the first inlet header space communicating with each first plate. it can. As a result, the flow rate of the first fluid flowing into the first flow path formed in each first plate can be balanced, so that the drift suppression effect can be improved.

(3) In one embodiment, in the configuration of (1) or (2),
The plurality of first plates and the plurality of second plates are alternately arranged along the stacking direction of the plurality of plates.
According to the configuration of (3) above, the plurality of first plates and the plurality of second plates are alternately arranged along the plate stacking direction, so that the first flow path formed in each first plate Since the volume of the first inlet header space that communicates with each other can be equally divided, the effect of suppressing the drift of the first fluid flowing into the first flow path formed in each first plate can be improved. In addition, since the first plate through which the first fluid flows and the second plate through which the second fluid flows are alternately arranged adjacent to each other in a laminated structure, reliable heat exchange is performed between the first fluid and the second fluid. Can do.

(4) In one embodiment, in any one of the configurations (1) to (3),
The first inlet header space is configured such that the flow path cross-sectional area gradually decreases as the distance between the plurality of first flow paths and the supply unit increases in each of the plurality of first plates (hereinafter, this configuration). Is also called “tapered structure”.)
According to the configuration of (4), since the first inlet header space has the tapered structure, the plurality of first flow paths formed in the first plates have the first fluid in order from the closest to the supply unit. Even if the flow rate of the first inlet header space decreases due to the diversion, the flow velocity of the first fluid flowing from the inlet header into each first flow path can be made equal.

As a result, it becomes possible to form an annular flow, which will be described later, in the first inlet header space and each of the first flow paths, and to suppress the uneven flow between the first flow paths by maintaining the annular flow in the first inlet header space. Therefore, the heat exchange performance between the first fluid and the second fluid can be improved in the plurality of first flow paths.
Further, in a structure in which a plurality of plates are stacked to form a flow path, by adopting a tapered structure, it is possible to easily cope with a large increase or decrease in the number of plates, and a complicated header structure is not obtained. In addition, it is possible to reliably supply the first fluid that can suppress the drift between the first flow paths.

(5) In one embodiment, in any one of the configurations (1) to (4),
The supply portion of the first fluid and the discharge portion of the first fluid are formed in the plate structure along the stacking direction.
According to the configuration of (5) above, the first fluid supply section and the discharge section are formed in the plate structure, so that the first fluid supply section and the discharge section are provided as separate structures outside the plate structure. There is no need to provide it. Furthermore, the piping for connecting the first fluid supply section and the first inlet header space and the piping for connecting the first fluid discharge section and the second outlet header space are not required, so the heat exchanger is made compact. In addition, the cost can be reduced.

(6) In one embodiment, in any one of the configurations (1) to (5),
In each of the plurality of first plates, the plurality of first flow paths are arranged in parallel,
In each of the plurality of second plates, the plurality of second flow paths are arranged in parallel.
According to the configuration of (6) above, since the plurality of first flow paths are arranged in parallel, the first inlet header space has the tapered structure of (4), so that the drift between the first flow paths is The suppression effect can be improved.
In addition, since the plurality of first flow paths and the plurality of second flow paths are both arranged in parallel, the first flow path and the second flow path can be disposed close to each other over the entire length of the flow path. Thereby, the heat exchange efficiency between the first fluid and the second fluid can be improved.

(7) In one embodiment, in any one of the configurations (1) to (6),
A diaphragm is provided at an outlet of the plurality of first flow paths formed in each of the plurality of first plates.
According to the configuration of the above (7), the pressure loss of each first flow path can be increased by providing the throttles at the outlets of the plurality of first flow paths, thereby reducing the pressure loss of each first flow path. The pressure loss difference between the first flow paths with respect to the absolute value can be relatively reduced, thereby improving the drift suppression effect between the plurality of first flow paths.

(8) In one embodiment, in any one of the configurations (1) to (7),
There is provided a restriction provided at an inlet portion of the plurality of first flow paths formed in each of the plurality of first plates.
According to the configuration of (8) above, by providing the throttles at the inlets of the plurality of first flow paths, it is possible to prevent the backflow that occurs when the first fluid vaporizes and rapidly expands in the first flow path. .

(9) In one embodiment, in any one of the configurations (1) to (8),
The plurality of first flow paths formed in the first inlet header space and the plurality of first plates have an annular flow of the first fluid flowing through the first inlet header space and the plurality of first flow paths. It is configured to form.
“Annular flow” refers to a flow in which the liquid phase is arranged in an annular shape on the wall surface of the flow path, and the gas phase is arranged on the center side of the flow path, forming a state in which the gas phase and the liquid phase are mixed. Yes.
According to the configuration of (9) above, since the first fluid is configured to form an annular flow in the first inlet header space and each first flow path, a plurality of pieces connected to the first inlet header space are provided. Since the gas and liquid flow in the first flow path in a mixed state, thereby the gas-liquid mixing ratio can be uniformly maintained in the first inlet header space and the plurality of first flow paths, The heat exchange performance with the second fluid can be improved.

(10) In one embodiment, in any one of the configurations (1) to (9),
The maximum width of the plurality of first channels formed in the plurality of first plates and the plurality of second channels formed in the plurality of second plates is 2 mm or less.
According to the configuration of (10) above, a plurality of first flow paths and second flow paths can be formed as fine flow paths having a diameter of 2 mm or less, so that a large number of first flow paths can be formed in the first plate. Many second flow paths can be formed in the second plate. Thereby, since the heat transfer area of these flow paths can be dramatically increased, the amount of heat exchange between the first fluid and the second fluid can be dramatically increased.

(11) In one embodiment, in any one of the configurations (1) to (10),
The second fluid supply section, the second inlet header space communicating with the supply section and the plurality of second flow paths, the second fluid discharge section, the discharge sections, and the plurality of second flow paths. A second outlet header space that communicates with the plate structure,
The second inlet header space and the second outlet header space are disposed on both sides of the plurality of first flow paths along a direction intersecting the plurality of first flow paths,
The plurality of second flow paths are:
An inlet side region and an outlet side region disposed along a direction intersecting the plurality of first flow paths;
An intermediate region disposed along the same direction as the plurality of first flow paths;
including.

According to the configuration of (11) above, since the second inlet header space and the second outlet header space of the second flow path are arranged along the direction intersecting the first flow path, the second inlet header space and the second The two outlet header spaces can be arranged without interfering with the first inlet header space and the first outlet header space of the first flow path, thereby increasing the degree of freedom of arrangement of the second inlet header space and the second outlet header space. be able to.
In addition, since the intermediate region of the second flow path is disposed along the same direction as the first flow path, the heat exchange performance between the first fluid and the second fluid in the intermediate region can be improved.

(12) In one embodiment, in any one of the configurations (1) to (11),
The first fluid and the second fluid are refrigerants used in a refrigerator constituting a refrigeration cycle, the first fluid is a primary refrigerant, and the second fluid exchanges heat with the primary refrigerant to exchange the primary refrigerant. It is a secondary refrigerant to be heated.
According to the configuration of (12) above, uneven flow can be suppressed between the plurality of first flow paths through which the primary refrigerant flows, and the heat exchange performance of the plurality of first flow paths can be made uniform. As a result, the heat exchange performance between the first fluid and the second fluid can be maintained high.

  According to one embodiment, in a heat exchanger that exchanges heat between a gas-liquid two-phase first fluid and a second fluid, the drift of the first fluid flowing into the plurality of heat exchange channels is suppressed, and the entire heat exchanger High heat exchange performance can be maintained.

It is a perspective view of the heat exchanger which concerns on one Embodiment. It is a front view of the heat exchanger which concerns on one Embodiment. It is a side view of the heat exchanger which concerns on one Embodiment. It is sectional drawing which follows the AA line in FIG. It is sectional drawing which follows the BB line in FIG. It is a front view which shows the surface of the 1st plate which concerns on one Embodiment. It is a front view which shows the back surface of the 1st plate which concerns on one Embodiment. It is sectional drawing which follows the C1C line in FIG. FIG. 7 is a cross-sectional view taken along line D-D in FIG. 6. It is a front view which shows the surface of the 2nd plate which concerns on one Embodiment. It is a front view which shows the back surface of the 2nd plate which concerns on one Embodiment. It is sectional drawing which follows the EE line | wire in FIG.

Hereinafter, some embodiments of the present invention will be described with reference to the accompanying drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in the embodiments or shown in the drawings are not intended to limit the scope of the present invention, but are merely illustrative examples.
For example, expressions expressing relative or absolute arrangements such as “in a certain direction”, “along a certain direction”, “parallel”, “orthogonal”, “center”, “concentric” or “coaxial” are strictly In addition to such an arrangement, it is also possible to represent a state of relative displacement with an angle or a distance such that tolerance or the same function can be obtained.
For example, an expression indicating that things such as “identical”, “equal”, and “homogeneous” are in an equal state not only represents an exactly equal state, but also has a tolerance or a difference that can provide the same function. It also represents the existing state.
For example, expressions representing shapes such as quadrangular shapes and cylindrical shapes represent not only geometrically strict shapes such as quadrangular shapes and cylindrical shapes, but also irregularities and chamfers as long as the same effects can be obtained. A shape including a part or the like is also expressed.
On the other hand, the expressions “comprising”, “comprising”, “comprising”, “including”, or “having” one constituent element are not exclusive expressions for excluding the existence of other constituent elements.

1 to 12 show a heat exchanger 10 according to an embodiment. 1 to 3 are general views of the heat exchanger 10, FIG. 4 is a cross-sectional view taken along line AA in FIG. 2, and FIG. 5 is a cross-sectional view taken along line BB in FIG. is there.
As shown in FIGS. 4 and 5, the heat exchanger 10 forms a plate structure 16 with a plurality of stacked plates including a plurality of first plates 12 and a plurality of second plates 14. A plurality of first flow paths 18 are formed in each of the plurality of first plates 12, and a plurality of second flow paths 20 are formed in each of the plurality of second plates 14.

6 to 9 show the first plate 12. 6 and 7 show the front and back surfaces of the first plate 12, FIG. 8 is a sectional view taken along the line CC in FIG. 6, and FIG. 9 is a sectional view taken along the line DD in FIG. It is. 8 and 9 show the first flow path 18 formed in the first plate 12.
10 to 12 show the second plate 14. 10 and 11 show the front and back surfaces of the second plate 14, and FIG. 12 is a cross-sectional view taken along line EE in FIG. 10, showing the second flow path 20 formed in the second plate 14. .

A first inlet header space 22 and a first outlet header space 24 are formed in the plate structure 16. The first inlet header space 22 communicates with the first fluid supply unit 26 and the plurality of first flow paths 18 formed in each first plate 12. The first outlet header space 24 communicates with the first fluid discharge portion 28 and the plurality of first flow paths 18 formed in each first plate 12.
The first outlet header space 24 forms a space penetrating along the plate stacking direction.

In the above configuration, the first fluid f ₁ (see FIG. 1) is in a gas-liquid two-phase state in at least a part of the first flow path 18. The first fluid flows into the plurality of first flow paths 18 from the first fluid supply unit 26 via the first inlet header space 22. The first fluid that flows through the plurality of first flow paths 18 exchanges heat with the second fluid f ₂ (see FIG. 1) that flows through the plurality of second flow paths 20, and is heated and evaporated by the second fluid, so that the first outlet It flows out to the first fluid discharge part 28 through the header space 24.

In FIG. 6, the pressure of the first fluid in the first fluid supply unit 26 is P _in , the pressure of the first fluid _in the first inlet header space 22 is P _1, and the first fluid in any first flow path 18 is a pressure of P _2, the pressure of the first fluid in the first outlet header space 24 and P _3, the pressure of the first fluid in the first outlet header space 24 and P _out. The pressure loss [Delta] P of the first fluid between the at all of the first flow path 18 and the first fluid supply unit 26 and the first fluid discharge section 28, the pressure loss [Delta] P ₁ of the first inlet header space 22, the first flow the pressure loss [Delta] P ₂ of the road 18, because the sum of the pressure loss [Delta] P ₃ of the first outlet header space 24, the following equation (1) and (2) holds.
ΔP = P _in −P _out
= ΔP ₁ + ΔP ₂ + ΔP ₃
= (P _in −P ₁ ) + (P ₁ −P ₃ ) + (P ₃ −P _out ) (1)
P ₁ > P ₂ > P ₃ (2)

At the outlet of the first flow path 18 through which the gas-liquid two-phase first fluid flows, the pressure loss of the first fluid is likely to increase due to the first fluid becoming steam in the first flow path 18. Accordingly, the first outlet header space first fluid pressure loss [Delta] P ₃ of the 24 large, pressure loss difference between the plurality of first flow path 18 increases.
According to the above configuration, the first outlet header space 24, for forming a space penetrating along the plate laminating direction, thereby reducing the pressure loss [Delta] P ₃ of the first outlet header space 24. As a result, the proportion of the first fluid pressure loss ΔP ₂ in the first flow path 18 relatively increases.
In addition, the pressure loss [Delta] P ₃ of the first outlet header space 24 is reduced, also reducing the difference in pressure loss at the outlet portion of the plurality of first flow path 18.

  Thus, since the difference in pressure loss at the outlets of the plurality of first flow paths 18 can be reduced, the first fluid and the second fluid in some of the first flow paths caused by the drift of the first fluid between the first flow paths. Decrease in heat exchange performance with can be suppressed. Therefore, since the heat exchange performance between the plurality of first flow paths can be made uniform, the heat exchange performance as a whole can be maintained high.

In one embodiment, as shown in FIGS. 6 and 10, the first inlet header space 22 is divided by a plurality of second plates 14 along the plate stacking direction.
According to the above configuration, the first inlet header space 22 is divided by the plurality of second plates 14 along the plate stacking direction, thereby reducing the volume of the first inlet header space 22 communicating with each first plate 12. it can. When the flow rate and the flow velocity are decreased, the gas phase and the liquid phase tend to be separated. However, according to the above configuration, the first inlet header space 22 is divided by the plurality of second plates 14 so that each first flow is separated. The flow rate of the first fluid flowing into the passage 18 can be balanced, and the decrease in the flow rate and the flow velocity can be suppressed due to the decrease in the volume of the first inlet header space 22, so that the drift suppression effect can be improved.

In one embodiment, as shown in FIGS. 4 and 5, the plurality of first plates 12 and the plurality of second plates 14 are alternately arranged along the plate stacking direction.
According to the above configuration, the plurality of first plates 12 and the plurality of second plates 14 are alternately arranged along the plate stacking direction, so that the first flow paths 18 formed in the first plates 12 Since the volume of the 1st inlet header space 22 connected can be equally divided | segmented, the drift suppression effect of the 1st fluid which flows in into the 1st flow path 18 formed in each 1st plate 12 can be improved. In addition, since the first plate 12 through which the first fluid flows and the second plate 14 through which the second fluid flows are alternately arranged adjacent to each other in a laminated structure, reliable heat exchange between the first fluid and the second fluid is achieved. It can be carried out.

In one embodiment, as shown in FIGS. 6 and 7, the first inlet header space 22 flows as the distance between the plurality of first flow paths 18 and the first fluid supply units 26 increases in each first plate 12. It has a tapered structure in which the road cross-sectional area gradually decreases.
According to the above configuration, since the first inlet header space 22 through which the gas-liquid two-phase first fluid flows has a tapered structure, an annular flow can be formed in the vicinity of the first fluid supply unit 26. Moreover, since it has a taper structure, a 1st fluid is shunted in order from the order close to the 1st fluid supply part 26 to the some 1st flow path 18 formed in each 1st plate 12, and the 1st inlet header. Even if the flow rate of the space 22 decreases, the flow rate of the first fluid flowing into the first flow paths 18 from the first inlet header space 22 can be made equal.

Thereby, since the annular flow can be maintained in the first inlet header space 22 and the uneven flow between the first flow paths can be suppressed, the heat of the first fluid f ₁ and the second fluid f ₂ in the plurality of first flow paths 18 can be achieved. Exchange efficiency can be improved.
Further, in a structure in which a plurality of plates are stacked to form a flow path, by adopting a tapered structure, even if the number of plates is greatly increased or decreased, it can be easily handled and a complicated header structure is not obtained. In addition, it is possible to reliably supply the first fluid that can suppress the drift between the first flow paths 18.

In one embodiment, as shown in FIGS. 6 and 7, the first fluid supply unit 26 and the first fluid discharge unit 28 are formed in the plate structure 16 along the plate stacking direction.
According to the above configuration, the first fluid supply unit 26 and the first fluid discharge unit 28 are formed on the plate structure 16, so that the first fluid supply unit 26 and the first fluid discharge unit 28 are outside the plate structure 16. It is no longer necessary to install them as separate components. Furthermore, the piping that connects the first fluid supply unit 26 and the first inlet header space 22 and the piping that connects the first fluid discharge unit 28 and the first outlet header space 24 become unnecessary. Thereby, the heat exchanger 10 can be reduced in size and cost.

In one embodiment, as shown in FIGS. 6 and 10, the plurality of first flow paths 18 are arranged in parallel in each first plate 12. In each second plate 14, the plurality of second flow paths 20 are arranged in parallel.
According to the above configuration, since the plurality of first flow paths 18 are arranged in parallel, the effect of suppressing the drift between the first flow paths can be improved by providing the first inlet header space 22 with a tapered structure.
Further, since the plurality of first flow paths 18 and the plurality of second flow paths 20 are arranged in parallel, the first flow path 18 and the second flow path 20 can be arranged close to each other over the entire length of the flow path. Thereby, the heat exchange efficiency between the first fluid and the second fluid can be improved.

In one embodiment, the plurality of first channels 18 and the plurality of second channels 20 are arranged in parallel at the same interval.
In one embodiment, the 1st channel 18 and the 2nd channel 20 are arranged in the position which overlaps in the plate lamination direction. Thereby, since the 1st flow path 18 and the 2nd flow path 20 can be arrange | positioned in the closest position, the heat exchange performance of a 1st fluid and a 2nd fluid can be improved to the maximum.

In one embodiment, as shown in FIG. 6, throttles 30 are provided at the outlets of the plurality of first flow paths 18 formed in each first plate 12.
According to the said structure, the pressure loss of each 1st flow path can be increased moderately by providing the aperture_diaphragm | restriction 30. FIG. Thereby, the pressure loss difference between the first flow paths with respect to the absolute value of the pressure loss of the first flow paths can be relatively reduced, and therefore, the drift suppression effect between the plurality of first flow paths can be improved.

In one embodiment, as shown in FIG. 6, throttles 32 are provided at the inlet portions of the plurality of first flow paths 18 formed in each of the plurality of first plates 12.
According to the above configuration, by providing the throttles 32 at the inlets of the plurality of first flow paths, it is possible to prevent the backflow caused by the first fluid being vaporized and rapidly expanding in the first flow path. In particular, when the throttle 30 is provided at the outlet portion of the first flow path 18, the pressure in the first flow path 18 increases, and thus a reverse flow is likely to occur. However, the reverse flow can be prevented by providing the throttle 32 at the inlet portion.

In one embodiment, the plurality of first flow paths 18 formed in the first inlet header space 22 and the plurality of first plates 12 are configured such that the first fluid forms an annular flow in these flow fields. ing. The configurations of the first inlet header space 22 and the first flow path 18, the properties (for example, density, viscosity coefficient, etc.) and the operating conditions (for example, flow rate, flow velocity, etc.) of the first fluid flowing through these are, for example, It is determined by a Baker diagram showing the flow pattern of the phase flow.
According to the above configuration, since the first fluid forms an annular flow in the first inlet header space 22 and the first flow path 18, the gas and liquid are mixed in these flow fields, and the gas and liquid are separated. Absent. Accordingly, since the gas-liquid mixing ratio can be maintained uniformly in the first inlet header space 22 and the first flow path 18, the heat exchange performance between the first fluid and the second fluid can be improved as a whole.

In one embodiment, as shown in FIGS. 5, 6, 8, 9, and 12, the plurality of first flow paths 18 formed in the plurality of first plates 12 and the plurality of second plates 14, respectively. The formed plurality of second flow paths 20 have a diameter of 2 mm or less (preferably 0.1 to 1.0 mm).
According to the above configuration, the first flow path 18 and the second flow path 20 are fine flow paths having a diameter of 2 mm or less, so that a large number of the first flow paths 18 can be formed in the first plate 12, and the second Many second flow paths 20 can be formed in the plate 14. Thereby, since the heat transfer area of these flow paths can be dramatically increased, the heat exchange efficiency between the first fluid and the second fluid can be dramatically increased.

Preferably, the diameter of the first channel 18 and the second channel 20 is 1 mm or less in order to increase the heat exchange performance. Preferably, from the viewpoint of ease of processing the first flow path 18 and the second flow path 20, the diameters of the first flow path 18 and the second flow path 20 are set to 0.1 mm or more.
In the illustrated embodiment, the cross sections of the first flow path 18 and the second flow path 20 are semicircular, but other shapes such as a rectangle and an ellipse may be used.

In one embodiment, as shown in FIGS. 2, 10, and 11, the second fluid supply unit 34, the second inlet header space 38 that communicates with the second fluid supply unit 34 and the plurality of second flow paths 20, A second fluid discharge part 36 and a second outlet header space 40 communicating with the second fluid discharge part 36 and the plurality of second flow paths 20 are formed in the plate structure 16.
Further, the second inlet header space 38 and the second outlet header space 40 are disposed on both sides of the plurality of first flow paths 18 along the direction intersecting with the plurality of first flow paths 18. Further, the plurality of second flow paths 20 are arranged in the same direction as the plurality of first flow paths 18, and the inlet side area 20 a and the outlet side area 20 c arranged along the direction intersecting with the plurality of first flow paths 18. And an intermediate region 20b disposed along.

According to the above configuration, since the second inlet header space 38 and the second outlet header space 40 of the second flow path 20 are arranged along the direction intersecting the first flow path 18, the second inlet header space 38 and The second outlet header space 40 can be arranged without interfering with the first inlet header space 22 and the first outlet header space 24 of the first flow path 18. Therefore, the freedom degree of arrangement | positioning of the 2nd entrance header space 38 and the 2nd exit header space 40 can be expanded.
Moreover, since the intermediate region 20b of the second flow path 20 is disposed along the same direction as the first flow path 18, the heat exchange performance between the first fluid and the second fluid in the intermediate area 20b can be improved.

In one embodiment, the first fluid and the second fluid are refrigerants used in a refrigerator constituting a refrigeration cycle. For example, the first fluid is a primary refrigerant that exchanges heat with the second fluid to cool the second fluid, and the second fluid is a secondary refrigerant that exchanges heat with the first fluid and heats the first fluid.
As a result, uneven flow can be suppressed between the plurality of first flow paths through which the primary refrigerant flows, the heat exchange performance of the plurality of first flow paths can be made uniform, and the first fluid and the second fluid can be made uniform as the entire first flow path. High heat exchange performance can be maintained.

In one embodiment, the first fluid is NH ₃ , the second fluid is CO ₂ , and the heat exchanger 10 is NH ₃ / CO _{2 where the} primary refrigerant is NH ₃ and the secondary refrigerant is CO ₂ , for example. It is a CO ₂ liquefier that is provided in the refrigerator and vaporizes the primary refrigerant by exchanging heat between the primary refrigerant and the secondary refrigerant.
In this CO ₂ liquefier, the uneven flow can be suppressed between the plurality of first flow paths through which NH ₃ flows, the heat exchange performance of the plurality of first flow paths 18 can be made uniform, and the pressure loss of the first flow path 18 can be reduced. Since it can suppress, the heat exchange performance of a primary refrigerant and a secondary refrigerant can be maintained highly.
The gas-liquid two-phase flow of NH ₃ having a large gas-liquid density ratio is particularly susceptible to drift, but according to the embodiment, it is possible to effectively suppress the drift of NH ₃ as the primary refrigerant in the plurality of first flow paths. .

In one embodiment, as shown in FIG. 1, end plates 42 and 44 are provided on both sides of the plate structure 16. One end plate 42 includes a hole 46 communicating with the first fluid supply unit 26, a hole 48 communicating with the first fluid discharge unit 28, a hole 50 communicating with the second fluid supply unit 34, and a second fluid discharge unit. A hole 52 communicating with 36 is formed. A first fluid inlet pipe 54 is provided so as to surround the hole 46, a first fluid outlet pipe 56 is provided so as to surround the hole 48, and a second fluid inlet pipe 58 is provided so as to surround the hole 50, A second fluid outlet pipe 60 is provided so as to surround the hole 52.
The first fluid inlet pipe 54 is connected to a first fluid supply pipe (not shown), the first fluid outlet pipe 56 is connected to a first fluid discharge pipe (not shown), and the second fluid inlet pipe 58 is a second fluid. The second fluid outlet pipe 60 is connected to a supply pipe (not shown), and the second fluid outlet pipe 60 is connected to a second fluid discharge pipe (not shown).
The other end plate 44 is a plate-like body having no holes or openings.

In one embodiment, as shown in FIGS. 1 and 3, the first plate 12, the second plate 14, and the end plates 42 and 44 are configured by flat plate-like bodies.
In one embodiment, the first plate 12, the second plate 14, and the end plates 42 and 44 are bonded to each other by a diffusion bonding method.
In one embodiment, as shown in FIGS. 1 and 3, the first plate 12, the second plate 14, and the end plates 42 and 44 have a rectangular outer shape.

In one embodiment, as shown in FIG. 1, the first fluid inlet tube 54 and the second fluid outlet tube 60 are disposed below, and the first fluid outlet tube 56 and the second fluid inlet tube 58 are disposed above. Are arranged along the vertical direction.
In one embodiment, the first plate 12 and the second plate 14 are made of a material having a high thermal conductivity coefficient and high strength. Accordingly, the heat exchange performance is good and the first plate 12 and the second plate 14 can be made thin.

  According to an embodiment, in a heat exchanger that exchanges heat between a gas-liquid two-phase first fluid and a second fluid, the heat exchange performance is suppressed by suppressing the drift of the first fluid flowing into the plurality of heat exchange channels. Highly maintainable.

DESCRIPTION OF SYMBOLS 10 Heat exchanger 12 1st plate 14 2nd plate 16 Plate structure 18 1st flow path 20 2nd flow path 20a Inlet side area | region 20b Middle area | region 20c Outlet side area | region 22 1st inlet header space 24 1st exit header space 26 First fluid supply unit 28 First fluid discharge unit 30, 32 Restriction 34 Second fluid supply unit 36 Second fluid discharge unit 38 Second inlet header space 40 Second outlet header space 42, 44 End plates 46, 48, 50, 52 hole 54 first fluid inlet pipe 56 first fluid outlet pipe 58 second fluid inlet pipe 60 second fluid outlet pipe f ₁ first fluid f ₂ second fluid

Claims (12)

A heat exchanger for exchanging heat between the first fluid and the second fluid to vaporize the first fluid,
A plurality of stacked layers including a plurality of first plates forming a plurality of first flow paths through which the first fluid flows, and a plurality of second plates forming a plurality of second flow paths through which the second fluid flows. Comprising a plate structure composed of
The first fluid is in a gas-liquid two-phase state in at least a part of the first flow path;
A first inlet header space communicating with the first fluid supply section and the plurality of first flow paths formed in each of the plurality of first plates; the first fluid discharge section; A first outlet header space communicating with the plurality of first flow paths formed in each of the one plate is formed in the plurality of first plates;
The heat exchanger according to claim 1, wherein the first outlet header space forms a space penetrating along a stacking direction of the plurality of plates including the plurality of second plates.   The heat exchanger according to claim 1, wherein the first inlet header space is divided by the plurality of second plates.   The heat exchanger according to claim 1 or 2, wherein the plurality of first plates and the plurality of second plates are alternately arranged along the stacking direction.   The first inlet header space is configured such that in each of the plurality of first plates, a channel cross-sectional area gradually decreases as the distance between the plurality of first channels and the supply unit increases. The heat exchanger according to any one of claims 1 to 3.   The said supply part of the said 1st fluid and the said discharge part of the said 1st fluid are formed in the said plate structure along the said lamination direction, The Claim 1 thru | or 4 characterized by the above-mentioned. Heat exchanger. In each of the plurality of first plates, the plurality of first flow paths are arranged in parallel,
6. The heat exchanger according to claim 1, wherein in each of the plurality of second plates, the plurality of second flow paths are arranged in parallel.   The heat exchanger according to any one of claims 1 to 6, further comprising a restriction provided at an outlet portion of the plurality of first flow paths formed in each of the plurality of first plates. .   The heat exchanger according to any one of claims 1 to 7, further comprising a restriction provided at an inlet portion of the plurality of first flow paths formed in each of the plurality of first plates. .   The plurality of first flow paths formed in the first inlet header space and the plurality of first plates have an annular flow of the first fluid flowing through the first inlet header space and the plurality of first flow paths. It is comprised so that it may form, The heat exchanger as described in any one of the Claims 1 thru | or 8 characterized by the above-mentioned.   The maximum width of the plurality of first flow paths formed in the plurality of first plates and the plurality of second flow paths formed in the plurality of second plates is 2 mm or less. The heat exchanger according to any one of 1 to 9. The second fluid supply section, the second inlet header space communicating with the supply section and the plurality of second flow paths, the second fluid discharge section, the discharge sections, and the plurality of second flow paths. A second outlet header space that communicates with the plate structure,
The second inlet header space and the second outlet header space are disposed on both sides of the plurality of first flow paths along a direction intersecting the plurality of first flow paths,
The plurality of second flow paths are:
An inlet side region and an outlet side region disposed along a direction intersecting the plurality of first flow paths;
An intermediate region disposed along the same direction as the plurality of first flow paths;
The heat exchanger according to any one of claims 1 to 10, characterized by comprising:   The first fluid and the second fluid are refrigerants used in a refrigerator constituting a refrigeration cycle, the first fluid is a primary refrigerant, and the second fluid exchanges heat with the primary refrigerant to exchange the primary refrigerant. The heat exchanger according to any one of claims 1 to 11, wherein the heat exchanger is a secondary refrigerant to be heated.

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