WO2020246003A1

WO2020246003A1 - Heat exchanger

Info

Publication number: WO2020246003A1
Application number: PCT/JP2019/022629
Authority: WO
Inventors: 潤宮本; 亮介末光; 長谷川　泰士; 和島　一喜
Original assignee: 三菱重工サーマルシステムズ株式会社
Priority date: 2019-06-06
Filing date: 2019-06-06
Publication date: 2020-12-10
Also published as: CN113677946A; US20220221232A1

Abstract

The purpose of the present invention is to provide a compact heat exchanger with which the generation of excessive pressure loss can be suppressed and a suitable flow rate can be assured in accordance with the volumetric changes of a fluid due to phase changes. This heat exchanger (1) comprises a flow path (8) which has an inlet (10) into which a fluid (6) flows and an outlet (11) through which the flowed fluid (6) flows out, and in which a phase change from a fluid phase to a gas phase occurs between the inlet (10) and the outlet (11), wherein the inside of the flow path (8) is formed in a resistance shape (12) so that the amount of flow path resistance applied to the flow of the fluid (6) is smaller on the outlet (11) side than the inlet (10) side.

Description

Heat exchanger

The present disclosure relates to a heat exchanger constituting a condenser or an evaporator of a refrigerator such as a turbo chiller, for example.

Conventionally, shell & tube heat exchangers, fin & tube heat exchangers, plate heat exchangers, plate fin heat exchangers, etc. have been used as heat exchangers that accompany fluid phase changes such as evaporators and condensers. ing. The shell and tube heat exchanger is configured to allow a single-phase fluid to flow through the tube, heat / cool the external fluid, and evaporate / condense the external fluid. The fin and tube heat exchanger is configured to allow gas to flow between the fins outside the tube to heat / cool the fluid inside the tube and evaporate / condense the fluid inside the tube. Plate heat exchangers and plate fin heat exchangers have a configuration in which a single-phase fluid flows between one plate and the fluid between the other plates is heated / cooled to evaporate / condense. Among these, as the plate fin heat exchanger, for example, the following Patent Documents 1 to 3 have been reported.

Special Table 2007-520682 Japanese Unexamined Patent Publication No. 2013-11479 Japanese Unexamined Patent Publication No. 2013-11340

When the fluid evaporates or condenses, the fluid undergoes a phase change, so the fluid volume changes significantly during the heat exchange process. In particular, in the portion of the fluid flow path in which the internal fluid is in the gas phase (gas side), the fluid volume in the fluid flow path becomes very large, and an excessive pressure loss may occur. On the other hand, if the fluid flow path is determined so that excessive pressure loss does not occur in the flow on the gas side, the flow velocity on the liquid side (the part where the fluid inside is in the liquid phase state) is significantly reduced, and the heat transfer performance is improved. There is a problem of decline.

In the case of shell & tube heat exchangers, unequal pitches are used that change the tube pitch etc. so that the heat transfer performance and pressure loss are appropriate in response to the volume change in the heat exchange process of the fluid. However, in this case, there is a problem that the volume of the shell & tube heat exchanger becomes large and the amount of fluid held on the side performing the phase change increases. On the other hand, fin & tube heat exchangers, plate heat exchangers, and plate fin heat exchangers can be made more compact than shell & tube heat exchangers, but the shape of the heat exchangers currently reported is , The shape does not correspond to the fluid volume change due to the phase change as described above.

The present disclosure has been made in view of such circumstances, and is a compact heat capable of suppressing the occurrence of excessive pressure loss and ensuring an appropriate flow velocity in response to the volume change of the fluid due to the phase change. The purpose is to provide a switch.

In order to solve the above problems, the present disclosure employs the following means.
The present disclosure includes an inflow port into which a fluid flows in and an outflow port from which the inflowing fluid flows out, and a flow path in which a phase change is performed from a liquid phase to a gas phase between the inflow port and the outflow port. A heat exchanger having a resistance shape formed inside the flow path in which the magnitude of the flow path resistance applied to the flow of the fluid is smaller on the outlet side than on the inlet side. provide.

When the fluid flowing into the flow path changes (evaporates) from the liquid phase to the gas phase by heat exchange in the flow path, the fluid volume increases. In this case, on the outlet side, an excessive pressure loss may occur due to an increase in the fluid volume. However, in the heat exchanger according to the first aspect of the present disclosure, the magnitude of the flow path resistance applied to the flow of the fluid inside the flow path is larger on the outlet side than on the inlet side (for example, in five stages). A smaller resistance shape is formed. Therefore, on the outlet side (gas side), the magnitude of the flow path resistance applied to the fluid flow is small, so that the occurrence of excessive pressure loss can be suppressed. On the other hand, on the inflow port side (liquid side), since the magnitude of the flow path resistance applied to the fluid flow is large, it is possible to prevent a significant decrease in the flow velocity of the fluid (that is, an appropriate flow velocity can be ensured). Can promote turbulence. As described above, in the heat exchanger according to the first aspect of the present disclosure, it is possible to suppress the occurrence of excessive pressure loss and promote turbulence in response to the volume change of the fluid due to the phase change. Therefore, such a heat exchanger is a heat exchanger having high heat transfer performance (evaporation heat transfer performance). Since it is only necessary to form a specific resistance shape inside the flow path, the heat exchanger can be made compact.

The present disclosure includes an inflow port into which a fluid flows in and an outflow port from which the inflowing fluid flows out, and a flow path in which a phase change is performed from a gas phase to a liquid phase between the inflow port and the outflow port. A heat exchanger having a resistance shape formed inside the flow path so that the magnitude of the flow path resistance applied to the flow of the fluid is larger on the outlet side than on the inlet side. provide.

When the fluid flowing into the flow path changes (condenses) from the gas phase to the liquid phase by heat exchange in the flow path, the fluid volume decreases. In this case, excessive pressure loss may occur on the inflow port side due to the large fluid volume. However, in the heat exchanger according to the second aspect of the present disclosure, the magnitude of the flow path resistance applied to the fluid flow inside the flow path is larger on the outlet side than on the inlet side (for example, in five stages). A resistance shape that increases is formed. Therefore, on the inflow port side (gas side), the magnitude of the flow path resistance applied to the fluid flow is small, so that the occurrence of excessive pressure loss can be suppressed. On the other hand, on the outlet side (liquid side), since the magnitude of the flow path resistance applied to the flow of the fluid is large, it is possible to prevent the flow velocity of the fluid from being significantly reduced (that is, an appropriate flow velocity can be ensured). Can promote turbulence. As described above, in the heat exchanger according to the second aspect of the present disclosure, it is possible to suppress the occurrence of excessive pressure loss and promote turbulence in response to the volume change of the fluid due to the phase change. Therefore, such a heat exchanger is a heat exchanger having high heat transfer performance (condensation performance). Since it is only necessary to form a specific resistance shape inside the flow path, the heat exchanger can be made compact.

In the heat exchanger, the resistance shape is preferably formed by a plate forming the flow path or a plurality of fins provided on the plate.

The resistance shape formed inside the flow path is thus formed by the plate forming the flow path (for example, in the plate heat exchanger) and the plurality of fins provided on the plate (for example, in the plate fin heat exchanger). Can be formed. Specifically, in the portion where the flow path resistance is increased, the plates and fins are arranged perpendicular to the fluid flow direction. On the other hand, in the portion where the flow path resistance is reduced, the plates and fins are arranged parallel to the fluid flow direction. By doing so, the resistance shape can be formed. Therefore, the heat exchangers of the present disclosure are particularly suitably applicable to plate heat exchangers and plate fin heat exchangers. Since the plate heat exchanger and the plate fin heat exchanger can be made compact, if the heat exchanger of the present disclosure is applied to the plate heat exchanger and the plate fin heat exchanger, the heat transfer performance is improved and compact. It becomes a heat exchanger.

In the heat exchanger, it is preferable that a separate flow path for heat exchange with the fluid flowing through the flow path is provided adjacent to the flow path.

In the heat exchanger of the present disclosure, by providing a separate flow path as described above, heat exchange can be performed between the fluid flowing through the flow path and the fluid flowing through the separate flow path.

In the heat exchanger, the same flow path resistance is imparted to the inside of the separate flow path between the inflow port where the fluid flowing through the separate flow path flows in and the outflow port where the inflowing fluid flows out. It is preferable that a resistance shape is formed.

As described above, if the above-mentioned flow path is combined with another flow path whose internal resistance shape is a resistance shape in which the magnitude of the flow path resistance applied to the fluid flow is constant, one fluid can be obtained. It can be suitably applied to a heat exchanger having a single-phase structure in which the other fluid undergoes a phase change.

In the heat exchanger, the inside of the separate flow path has a resistance shape in which the flow path resistance is larger at the outlet where the inflowing fluid flows out than at the inflow port where the fluid flowing through the separate flow path flows in. It is preferable that a resistance shape having a small flow path resistance is formed.

In the heat exchanger of the present disclosure, for example, the flow path in the first aspect and the flow path in the second aspect can be combined. That is, the heat exchanger of the present disclosure can be suitably applied to a heat exchanger in which one fluid evaporates in the flow path and the other fluid condenses in the flow path. ..

The heat exchanger of the present disclosure is a compact heat exchanger that can suppress the occurrence of excessive pressure loss in response to the volume change of the fluid due to the phase change and can secure an appropriate flow velocity.

It is a perspective exploded view which shows the structure of the heat exchanger (plate fin heat exchanger) which concerns on 1st Embodiment of this disclosure. It is a top view which shows the flow path in the heat exchanger which concerns on 1st Embodiment of this disclosure. It is a top view which shows the flow path in the heat exchanger which concerns on 2nd Embodiment of this disclosure. It is an image figure which looked at the flow path and another flow path in the heat exchanger which concerns on 3rd Embodiment of this disclosure from the side surface in the longitudinal direction. FIG. 5 is an image view of a flow path and another flow path in the heat exchanger according to the fourth embodiment of the present disclosure as viewed from the longitudinal side surface.

Hereinafter, an embodiment of the heat exchanger according to the present disclosure will be described with reference to the drawings.
In the following embodiment, a case where the heat exchanger according to the present disclosure is applied to a plate fin heat exchanger will be described as an example.

[First Embodiment]
Hereinafter, the first embodiment of the present disclosure will be described with reference to FIGS. 1 and 2.
FIG. 1 is a perspective exploded view showing the structure of the heat exchanger (plate fin heat exchanger) according to the present embodiment. The heat exchanger 1 shown in FIG. 1 is used for a condenser or an evaporator of a refrigerator such as a turbo chiller, for example. In the heat exchanger 1, plates (first plate) 2a and plates (second plate) 2b are alternately laminated and joined, bosses 3a and 3b are attached to the first plate 2a at the start end, and the first plate at the end ends. It has a structure in which the cover plate 4 is attached to 2a.

Inner fins

5a and 5b are provided on the surfaces of the first plate 2a and the second plate 2b on the cover plate 4 side, respectively.

The fluid (first fluid) 6 flows into the heat exchanger 1 from the boss 3a, and the fluid (second fluid) 7 flows into the heat exchanger 1 from the boss 3b. The first fluid 6 circulates in the flow path 8 formed between the second plate 2b and the inner fin 5a. The second fluid 7 is formed between the first plate 2a and the inner fin 5b, and circulates in another flow path 9 adjacent to the flow path 8.

With such a configuration, in the heat exchanger 1, the flow path 8 of the first fluid 6 and the separate flow path 9 of the second fluid 7 are alternately arranged, and between the two

fluids

6 and 7. The structure is such that heat exchange is performed.

Next, FIG. 2 is shown, and the flow path 8 of the present embodiment will be described in more detail.
FIG. 2 is a plan view showing a flow path 8 in the heat exchanger 1 of the present embodiment.

As shown in FIG. 2, the flow path 8 has an inflow port 10 into which the first fluid 6 flows in and an outflow port 11 from which the inflowing first fluid 6 flows out. In the flow path 8, the first fluid 6 undergoes a phase change from a liquid phase to a gas phase between the inflow port 10 and the outflow port 11. That is, the heat exchanger 1 is used as an evaporator for evaporating the refrigerant.

Inside the flow path 8, a resistance shape 12 is formed in which the magnitude of the flow path resistance applied to the flow of the first fluid 6 is smaller on the outflow port 11 side than on the inflow port 10 side. The resistance shape 12 is formed so that the magnitude of the flow path resistance decreases in five steps from the inflow port 10 side to the outflow port 11 side. In the present embodiment, the resistance shape 12 is formed by a plurality of fins 13 provided on the first plate 2a.

Specifically, in the portion where the flow path resistance is increased (liquid side), the fins 13 are arranged perpendicular to the flow direction of the fluid 6, and the fins 13 are arranged from the inflow port 10 side toward the outflow port 11 side. (The length in the direction perpendicular to the flow direction of the fluid 6) is shortened. On the other hand, in the portion where the flow path resistance is reduced (gas side), the fins 13 are arranged parallel to the flow direction of the fluid 6, and the number of fins 13 increases from the inflow port 10 side toward the outflow port 11. Arrange from dense to coarse.

According to the present embodiment, the following functions and effects are obtained by the configuration described above.
In the heat exchanger 1 according to the present embodiment, the magnitude of the flow path resistance applied to the flow of the fluid 6 inside the flow path 8 becomes smaller in five steps from the inflow port 10 side to the outflow port 11 side. 12 is formed. Therefore, on the outlet 11 side (gas side), the magnitude of the flow path resistance applied to the flow of the fluid 6 is small, so that the occurrence of excessive pressure loss can be suppressed. On the other hand, on the inflow port 10 side (liquid side), since the magnitude of the flow path resistance applied to the flow of the fluid 6 is large, it is possible to prevent the flow velocity of the fluid 6 from being significantly reduced (that is, an appropriate flow velocity can be secured). ) And turbulence can be promoted. As described above, in the heat exchanger 1 according to the present embodiment, it is possible to suppress the occurrence of excessive pressure loss and promote turbulence in response to the volume change of the fluid 6 due to the phase change. Therefore, such a heat exchanger 1 is a heat exchanger 1 having high heat transfer performance (evaporation heat transfer performance). Since it is only necessary to form a specific resistance shape 12 inside the flow path 8, the heat exchanger 1 can be made compact.

The resistance shape 12 formed inside the flow path 8 can be formed by a plurality of fins 13 provided on the first plate 2a (in the plate fin heat exchanger) in this way. Therefore, the heat exchanger 1 of the present embodiment is particularly suitably applicable to the plate fin heat exchanger. Since the plate fin heat exchanger can be made compact, if the heat exchanger 1 of the present embodiment is applied to the plate fin heat exchanger, the heat transfer performance is improved and the heat exchanger 1 becomes compact.

The resistance shape 12 described above can also be formed by the first plate 2a constituting the flow path 8 (in the plate heat exchanger). Therefore, the heat exchanger 1 of the present embodiment is also suitably applicable to the plate heat exchanger. Since the plate heat exchanger can also be made compact, if the heat exchanger 1 of the present embodiment is applied to the plate heat exchanger, the heat transfer performance is improved and the heat exchanger 1 becomes compact as described above.

In the present embodiment, as shown in FIG. 2, a resistance shape 12 is formed in which the magnitude of the flow path resistance applied to the flow of the fluid 6 decreases in five steps from the inflow port 10 side to the outflow port 11 side. However, the explanation is not limited to this. The magnitude of the flow path resistance can be reduced from the inflow port 10 side to the outflow port 11 side, preferably in 3 to 10 steps.

[Second Embodiment]
Next, the second embodiment of the present disclosure will be described with reference to FIG.
The basic configuration of the present embodiment is basically the same as that of the first embodiment, but the first embodiment is a point in which the first fluid 26 undergoes a phase change from a gas phase to a liquid phase in the flow path 28. , And the structure of the resistance shape 22 is different. Therefore, in the present embodiment, this different part will be described, and the description of other overlapping parts will be omitted.
The same components as those in the first embodiment are designated by the same reference numerals, and the duplicated description thereof will be omitted.

FIG. 3 is a plan view showing a flow path 28 in the heat exchanger 21 of the present embodiment.
In the flow path 28 shown in FIG. 3, the first fluid 26 undergoes a phase change from a gas phase to a liquid phase between the inflow port 10 and the outflow port 11. That is, the heat exchanger 1 is used as a condenser for condensing the refrigerant. Inside the flow path 28, a resistance shape 22 is formed in which the magnitude of the flow path resistance applied to the flow of the first fluid 26 is larger on the outflow port 11 side than on the inflow port 10 side. The resistance shape 22 is formed so that the magnitude of the flow path resistance increases in five steps from the inflow port 10 side to the outflow port 11 side. The resistance shape 22 is formed by a plurality of fins 13 provided on the first plate 2a as in the first embodiment.

Specifically, in the portion where the flow path resistance is reduced (gas side), the fins 13 are arranged parallel to the flow direction of the fluid 26, and the fins 13 are arranged from the inflow port 10 side toward the outflow port 11 side. Arrange so that the number of is coarse to dense. On the other hand, in the portion where the flow path resistance is increased (liquid side), the fins 13 are arranged perpendicular to the flow direction of the fluid 26, and the length of the fins 13 increases from the inflow port 10 side to the outflow port 11 side. (Length in the direction perpendicular to the flow direction of the fluid 26) is lengthened.

According to the present embodiment, the following functions and effects are obtained by the configuration described above.
In the heat exchanger 21 according to the present embodiment, the magnitude of the flow path resistance applied to the flow of the fluid 26 inside the flow path 28 increases in five steps from the inflow port 10 side to the outflow port 11 side. 22 is formed. Therefore, on the inflow port 10 side (gas side), the magnitude of the flow path resistance applied to the flow of the fluid 26 is small, so that the occurrence of excessive pressure loss can be suppressed. On the other hand, on the outlet 11 side (liquid side), since the magnitude of the flow path resistance applied to the flow of the fluid 26 is large, it is possible to prevent the flow velocity of the fluid 26 from being significantly reduced (that is, an appropriate flow velocity can be secured). ), And turbulence can be promoted. As described above, in the heat exchanger 21 according to the present embodiment, it is possible to suppress the occurrence of excessive pressure loss and promote turbulence in response to the volume change of the fluid 26 due to the phase change. Therefore, such a heat exchanger 21 is a heat exchanger 21 having high heat transfer performance (condensation performance). Since it is only necessary to form a specific resistance shape 22 inside the flow path 28, the heat exchanger 21 can be made compact.

In the present embodiment, as shown in FIG. 3, when a resistance shape 22 is formed in which the magnitude of the flow path resistance applied to the flow of the fluid 26 increases in five steps from the inflow port 10 side to the outflow port 11 side. However, the explanation is not limited to this. The magnitude of the flow path resistance can be increased from the inflow port 10 side to the outflow port 11 side, preferably in 3 to 10 steps.

[Third Embodiment]
Next, the third embodiment of the present disclosure will be described with reference to FIG.
The basic configuration of the present embodiment is basically the same as that of the second embodiment, but is the same as that of the second embodiment inside the separate flow path 49 between the inflow port 40 and the outflow port 41. The difference is that the resistance shape 42 that imparts the flow path resistance of is formed. Therefore, in the present embodiment, this different part will be described, and the description of other overlapping parts will be omitted.
The same components as those in the second embodiment are designated by the same reference numerals, and the duplicated description thereof will be omitted. In FIG. 4, the shapes of the resistance shapes 22 and 42 are conceptually shown, but this is just an image diagram.

FIG. 4 is an image view of the flow path 28 and the separate flow path 49 in the heat exchanger 31 according to the present embodiment as viewed from the side surface in the longitudinal direction. As shown in FIG. 4, in the flow path 28, the first fluid 26 undergoes a phase change from a gas phase to a liquid phase between the inflow port 10 and the outflow port 11. Inside the flow path 28, a resistance shape 22 is formed in which the magnitude of the flow path resistance applied to the flow of the first fluid 26 is larger on the outflow port 11 side than on the inflow port 10 side.

On the other hand, the separate flow path 49 has an inflow port 40 into which the second fluid 47 flows in and an outflow port 41 from which the inflowing second fluid 47 flows out. In the separate flow path 49, the second fluid 47 does not undergo a phase change between the inflow port 40 and the outflow port 41, and flows through the separate flow path 49 as a liquid phase (that is, is a single phase). Inside the separate flow path 49, a resistance shape 42 that imparts the same flow path resistance is formed between the inflow port 40 and the outflow port 41.

According to the present embodiment, the following functions and effects are obtained by the configuration described above.
As described above, the internal resistance shape 42 is a separate flow path 49 having a resistance shape 42 in which the magnitude of the flow path resistance applied to the flow of the fluid 47 is constant, and the flow path according to the second embodiment described above. Can be combined with 28. That is, the present disclosure can be suitably applied to the heat exchanger 31 in which one fluid 47 is single-phase and the other fluid 26 undergoes a phase change.

[Fourth Embodiment]
Next, the fourth embodiment of the present disclosure will be described with reference to FIG.
The basic configuration of the present embodiment is basically the same as that of the third embodiment, but the configuration of the resistance shape 52 formed inside the separate flow path 59 is different from that of the third embodiment. Therefore, in the present embodiment, this different part will be described, and the description of other overlapping parts will be omitted.
The same components as those in the third embodiment are designated by the same reference numerals, and the duplicated description thereof will be omitted. In FIG. 5, the shapes of the resistance shapes 22 and 52 are conceptually shown, but this is just an image diagram.

FIG. 5 is an image view of the flow path 28 and the separate flow path 59 in the heat exchanger 51 according to the present embodiment as viewed from the side surface in the longitudinal direction. As shown in FIG. 5, in the separate flow path 59 according to the present embodiment, the second fluid 57 undergoes a phase change from a liquid phase to a gas phase between the inflow port 40 and the outflow port 41. Inside the separate flow path 59, a resistance shape 52 is formed in which the flow path resistance of the outflow port 41 is smaller than that of the inflow port 40. That is, the configuration of the separate flow path 59 is substantially the same as the configuration of the flow path 8 in the first embodiment.

According to the present embodiment, the following functions and effects are obtained by the configuration described above.
In the heat exchanger 51 of the present embodiment, for example, the flow path 8 (separate flow path 59) in the first embodiment and the flow path 28 in the second embodiment can be combined. That is, the heat exchanger 51 of the present embodiment is configured such that one fluid 57 evaporates in the flow path 8 (separate flow path 59) and the other fluid 26 condenses in the flow path 28. It can be suitably applied to the exchanger 51.

In the embodiment described above, the case where the heat exchanger of the present disclosure is applied to the plate fin heat exchanger has been described as an example, but the present disclosure is not limited to this. Specifically, the heat exchanger of the present disclosure is also applicable to a plate heat exchanger, a fin & tube heat exchanger, and the like. The heat exchangers of the present disclosure are preferably applied to plate heat exchangers and plate fin heat exchangers.

1,21,31,51 Heat exchanger 2a plate (first plate)
2b plate (second plate)
3a, 3b Boss 4

Cover plate

5a,

5b Inner fins

6,26 Fluid (first fluid)
7,47,57 fluid (second fluid)
8,28

Channels

9, 49, 59

Separate channels

10, 40

Inlet

11, 41

Outlet

12, 22, 42, 52 Resistance shape 13 fins

Claims

It has an inflow port into which a fluid flows in and an outflow port from which the inflowing fluid flows out, and also has a flow path in which a phase change is performed from a liquid phase to a gas phase between the inflow port and the outflow port.
A heat exchanger in which a resistance shape is formed inside the flow path so that the magnitude of the flow path resistance applied to the flow of the fluid is smaller on the outlet side than on the inlet side.
It has an inflow port into which a fluid flows in and an outflow port from which the inflowing fluid flows out, and also has a flow path in which a phase change is performed from a gas phase to a liquid phase between the inflow port and the outflow port.
A heat exchanger in which a resistance shape is formed inside the flow path so that the magnitude of the flow path resistance applied to the flow of the fluid is larger on the outlet side than on the inlet side.
The heat exchanger according to claim 1 or 2, wherein the resistance shape is formed by a plate forming the flow path or a plurality of fins provided on the plate.
The heat exchanger according to any one of claims 1 to 3, wherein a separate flow path for heat exchange with the fluid flowing through the flow path is provided adjacent to the flow path.
Inside the separate flow path, a resistance shape is formed that imparts the same flow path resistance between the inflow port into which the fluid flowing through the separate flow path flows in and the outflow port from which the inflowing fluid flows out. The heat exchanger according to claim 4.
Inside the separate flow path, the outflow port where the inflowing fluid flows out has a resistance shape in which the flow path resistance is larger or the flow path resistance is smaller than the inflow port where the fluid flowing through the other flow path flows in. The heat exchanger according to claim 4, wherein a resistance shape is formed.