JP2020012563A - Microchannel heat exchanger and refrigeration cycle device - Google Patents

Abstract

To provide a microchannel heat exchanger which can prevent clogging of a passage.SOLUTION: A microchannel heat exchanger 1 includes: a heat exchanger body 10 having multiple microchannels 100; upstream headers 21, 22 which communicate with the multiple microchannels 100 and into which a fluid is introduced; and a stirring part 40 which stirs the fluid introduced into the upstream headers 21, 22. The stirring part 40 may have a stationary member 41 in a form that changes a flows state of the fluid.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a microchannel heat exchanger having a fine flow path and a refrigeration cycle apparatus including the same.

  2. Description of the Related Art A microchannel heat exchanger having a microchannel formed by microfabrication such as chemical etching as a liquid or gas flow path is known (Patent Document 1). The microchannel is formed between the metal plates by, for example, laminating a plurality of metal plates in which fine grooves are processed. The laminated metal plates are integrated by diffusion bonding or the like and assembled with the header.

The microchannel heat exchanger includes a first microchannel group through which one of the heating fluid and the fluid to be heated flows, and a second microchannel group through which the other flows. Heat is exchanged between the heating fluid and the fluid to be heated via a partition separating the first microchannel group and the second microchannel group.
According to the microchannel heat exchanger, since the microchannel has the small diameter microchannel, a large heat transfer area per unit volume can be secured as compared with the conventional heat exchanger. Therefore, further downsizing and higher performance of the device are expected by practical use of the device including the microchannel heat exchanger.

By the way, not only the microchannel heat exchanger but also a pipe through which a fluid flows is connected to the heat exchanger. The fluid flowing through the pipe contains foreign substances such as copper powder generated during the pipe installation and iron powder caused by wear of iron-based members such as a compressor.
In order to prevent the restriction or the like from being blocked by such foreign matter, in Patent Document 2, the foreign matter is collected by a sludge filter installed inside the pipe.

Patent No. 5185975 JP-A-10-300286

Even if a filter is installed in the pipe upstream of the heat exchanger to trap foreign matter, when fine foreign matter such as iron powder passes through the filter and flows into the header of the heat exchanger, the flow velocity is reduced. Agglomerates easily inside small headers. Then, since the diameter of the microchannel is small with respect to the aggregate of the aggregated foreign matter, the microchannel may be blocked by the foreign matter.
Therefore, an object of the present invention is to provide a microchannel heat exchanger that can prevent the passage from being blocked.

  The microchannel heat exchanger of the present invention includes a heat exchanger body having a plurality of microchannels, an upstream header communicating with the plurality of microchannels, and introducing a fluid, and a stirring unit for stirring the fluid flowing into the upstream header. And the following.

  In the microchannel heat exchanger according to the present invention, it is preferable that the agitating section has a stationary member configured to change the state of the flow of the fluid.

  In the microchannel heat exchanger according to the present invention, it is preferable that a region where the stirring section is arranged in the upstream header is divided into a plurality of sections, and a stationary member is arranged in each of the plurality of sections.

  In the microchannel heat exchanger of the present invention, it is preferable that the stirring unit has a rotating member that is rotated and a driving unit that drives the rotating member.

  In the microchannel heat exchanger of the present invention, it is preferable that the agitating section is disposed near the opening of the microchannel inside the upstream header.

  In the microchannel heat exchanger according to the present invention, the plurality of microchannels include a first microchannel group and a second microchannel group, and the first microchannel group and the second microchannel group receive a fluid in parallel or in opposition. The first upstream header, which flows in a state of flow and communicates with the first group of microchannels and into which the fluid is introduced, is located on an extension of the first group of microchannels extending linearly and communicates with the second group of microchannels. Preferably, the second upstream header into which the fluid is introduced is located at a position off the extension.

  In the microchannel heat exchanger according to the present invention, the plurality of microchannels include a first microchannel group and a second microchannel group, and a direction of a fluid flowing through the first microchannel group and a fluid flowing through the second microchannel group. The first upstream header, which is orthogonal to the first microchannel group and communicates with the first microchannel group and into which the fluid is introduced, is located on an extension of the first microchannel group that extends linearly, and is connected to the second microchannel group. The second upstream header, into which the fluid is introduced, is preferably located on an extension of the second microchannel group extending linearly.

  In addition, the refrigeration cycle apparatus of the present invention includes the above-described microchannel heat exchanger, a compressor that compresses a refrigerant as a fluid, a first heat exchanger that exchanges heat between the refrigerant and a heat source, and reduces the pressure of the refrigerant. And a second heat exchanger for exchanging heat between the refrigerant and the heat load. The microchannel heat exchanger includes a first microchannel group and a second microchannel group. It is characterized in that heat is exchanged between a first refrigerant flowing through one microchannel group and a second refrigerant flowing through a second microchannel group.

  ADVANTAGE OF THE INVENTION According to this invention, even if a foreign substance aggregates inside the upstream header, the aggregated foreign substance can be prevented from reaching the microchannel by dispersing the foreign substance by the stirring unit. Then, since the aggregation of foreign substances can be suppressed at the opening of the microchannel, the microchannel can be prevented from being blocked even if the microchannel is easily clogged due to its small diameter.

It is a top view showing the microchannel heat exchanger concerning a 1st embodiment. (A) is a schematic diagram of a group of microchannels which the heat exchanger shown in FIG. 1 has. (B) is a schematic diagram of microchannel groups having different flow path shapes. It is a figure which shows typically the refrigerant circuit of the refrigeration cycle apparatus which is an air conditioner etc. FIG. 4 is a sectional view taken along the line IV-IV of FIG. 1, showing an upstream header and a microchannel. It is a perspective view which shows the stationary member of the stirring part with which the heat exchanger shown in FIG. 1 is provided. It is a side view which shows the other example of the stationary member of a stirring part. (A) And (b) is a figure which shows the modification of 1st Embodiment. (B) is a sectional view taken along line VIIb-VIIb of (a). It is a top view showing the microchannel heat exchanger concerning a 2nd embodiment. (A) is an exploded perspective view showing a cross-flow type microchannel heat exchanger according to the third embodiment. (B) is a sectional view taken along line IXb-IXb of (a).

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
First, the configuration of the microchannel heat exchanger 1 common to each embodiment will be described with reference to FIGS. 1 and 2.
As shown in FIG. 1, the microchannel heat exchanger 1 has a heat exchanger body 10 having a plurality of microchannels 100 as flow paths, and communicates with the plurality of microchannels 100 and is assembled to the heat exchanger body 10. It has upstream headers 21 and 22 and downstream headers 31 and 32.

  As described later, the microchannel heat exchangers 1 to 3 of each embodiment include a stirring unit 40 in the upstream headers 21 and 22 for stirring the refrigerant containing the foreign matter 9 such as iron powder which easily aggregates inside the header. Is the main feature.

  The microchannel heat exchanger 1 is incorporated in, for example, a refrigerant circuit shown in FIG. 3 to constitute a refrigeration cycle device 8 such as an air conditioner, a refrigerator, or a water heater. The microchannel heat exchanger 1 is connected to other components (81 to 84) of the refrigeration cycle by piping.

The refrigerant circuit 80 provided in the refrigeration cycle device 8 includes a compressor 81 for compressing the refrigerant, a first heat exchanger 82 for exchanging heat between the refrigerant and a heat source, and a pressure reducing valve such as an expansion valve for reducing the pressure of the refrigerant. It comprises a part 83, a second heat exchanger 84 for exchanging heat between the refrigerant and the heat load, and the microchannel heat exchanger 1.
When the refrigeration cycle device 8 serving as an air conditioner performs a cooling operation, the micro-channel heat exchanger 1 uses the first heat exchanger 82 to exchange heat with outside air (heat source) and condensed refrigerant and second heat. The heat exchange with the indoor air (heat load) by the exchanger 84 causes the refrigerant evaporated to exchange heat. By such heat exchange, the refrigerant can be supercooled.

The microchannel heat exchanger 1 includes a relatively high-temperature refrigerant (a first refrigerant that is a heating refrigerant) flowing through the refrigerant circuit 80 and a relatively low-temperature refrigerant (a second refrigerant that is a heated refrigerant) also flowing through the refrigerant circuit 80. (A refrigerant).
The first refrigerant is, for example, the refrigerant flowing out of the first heat exchanger 82 in FIG. 3 and corresponds to the first microchannel group 101. The second refrigerant is, for example, the refrigerant flowing out of the second heat exchanger 84 in FIG. 3 and corresponds to the second microchannel group 102.

In FIG. 1, the direction in which the first refrigerant flows through the first microchannel group 101 is indicated by a broken-line arrow, and the direction in which the second refrigerant flows through the second microchannel group 102 is indicated by a solid-line arrow.
The first refrigerant and the second refrigerant exchange heat while flowing in the microchannel 100 in parallel in the same direction. The microchannel heat exchanger 1 shown in FIG. 1 is configured as a parallel flow type.

(header)
The first upstream header 21 and the first downstream header 31 correspond to the first refrigerant and communicate with the first microchannel group 101.
The second upstream header 22 and the second downstream header 32 correspond to the second refrigerant and communicate with the second microchannel group 102.

In each of the headers 21 and 31 for the first refrigerant and the headers 22 and 32 for the second refrigerant, the refrigerant flows smoothly through the microchannel 100 in consideration of the pressure loss and the like of the first refrigerant and the second refrigerant. Thus, an appropriate flow path cross-sectional area and volume are ensured.
In addition, the upstream headers 21 and 22 have a sufficient volume to accommodate the stirring section 40.
Each of the headers 21, 22, 31, and 32 can be configured in an appropriate form. For example, the upstream header 21 shown in FIG. 1 has a constant flow channel cross-sectional area, but has an upstream header spread toward the microchannel 100 such that the flow channel cross-sectional area gradually increases toward the microchannel 100. 21 can also be configured. The same applies to the other headers 22, 31, and 32.

(Flow of the first refrigerant and the second refrigerant)
The first refrigerant is introduced into the first upstream header 21 from the introduction part 201 to which the refrigerant pipe is connected as shown by the white arrow in FIG. Distributed to The first refrigerant flowing through the microchannels 100 merges at the first downstream header 31 and flows out of the discharge unit 301 to the refrigerant circuit 80.
The second refrigerant is introduced into the second upstream header 22 from the introduction section 202 to which the refrigerant pipe is connected, as shown by the black arrow in FIG. 1, and flows into the individual microchannels 100 forming the second microchannel group 102. Be distributed. The second refrigerant flowing through the microchannels 100 merges at the second downstream header 32, and flows out of the discharge part 302 to the refrigerant circuit 80.

  The microchannel heat exchanger 1 is not limited to the parallel flow type, but may be a counter flow type or a cross flow type. In the counterflow type, for example, as shown in FIG. 8, the direction in which the first refrigerant flows through the first microchannel group 101 and the direction in which the second refrigerant flows through the second microchannel group 102 are opposite to each other. The microchannel heat exchanger 1 shown in FIG. 3 is also described in a counterflow type. In the cross-flow type, for example, as shown in FIG. 9, the direction in which the first refrigerant flows through the first microchannel group 101 and the direction in which the second refrigerant flows through the second microchannel group 102 are orthogonal to each other.

(Micro channel)
The microchannel 100 is formed in an arbitrary cross-sectional shape by micromachining such as etching on the base material of the heat exchanger body 10 formed of a metal material such as stainless steel, copper, copper alloy, aluminum, and aluminum alloy. ing.
The size of the flow channel of the microchannel 100 is, for example, less than 1 mm in diameter. The length and number of the microchannels 100 are appropriately determined according to the heat exchange capacity required for the heat exchanger body 10.
The size of the flow channel of the microchannel 100 may be set to a few mm or less in diameter where the influence of the surface tension of the liquid phase flowing through the microchannel 100 appears. The size of the flow channel of the microchannel 100 can be set to an appropriate size generally included in the category of the microchannel.

The heat exchanger body 10 having the microchannel 100 is configured by laminating a plurality of metal plates 11 in which fine grooves 11A are processed at a predetermined pitch, as shown in FIG. 2A, for example.
The heat exchanger body 10 is formed in a rectangular parallelepiped shape as a whole by stacking the metal plates 11. The laminated metal plates 11 are integrated by a method such as diffusion bonding.
The headers 21, 22, 31, 32 can be assembled to the heat exchanger body 10 by diffusion bonding.

As shown in FIG. 2A, a large number of grooves 11A having a semicircular cross section are formed in each metal plate 11 in parallel along a direction perpendicular to the paper surface. By overlapping the surfaces on which the grooves 11A are formed, the microchannels 100 having a circular cross section are formed between the adjacent metal plates 11.
As shown in FIG. 2B, the microchannel 100 may be formed between a metal plate 11 having a groove 11B having a rectangular cross section and an adjacent metal plate 11.

The microchannels 100 are arranged in one direction (x direction) in the in-plane direction of the metal plate 11 and also arranged in the direction in which the metal plates 11 are stacked (y direction). A set of microchannels 100 arranged in the x direction along the surface of the metal plate 11 is referred to as a “stage” of the heat exchanger.
In the example shown in FIGS. 2A and 2B, the microchannels 100 are arranged such that the lower microchannel 100 is located immediately below the microchannel 100 in a certain stage. The present invention is not limited to this, and the microchannels 100 in a certain stage and the microchannels 100 in the lower stage may be arranged (in a staggered manner) so as to shift in the x direction.

The first microchannel group 101 includes a plurality of microchannels 100 located at every other stage in the stacking direction y.
The second group of microchannels 102 includes the remaining stages of microchannels 100.
2A and 2B, the opening of the first microchannel group 101 through which the first refrigerant flows is shown in white, and the opening of the second microchannel group 102 through which the second refrigerant flows is shown in black. Heat is exchanged between the first refrigerant and the second refrigerant via a partition (metal base) separating the first microchannel group 101 and the second microchannel group 102.
For efficient heat exchange, it is preferable that the first microchannel group 101 and the second microchannel group 102 are alternately arranged in the stacking direction y as shown in FIGS. 2 (a) and 2 (b).
However, the first micro channel group 101 and the second micro channel group 102 do not necessarily have to be arranged alternately. Further, the first microchannel group 101 and the second microchannel group 102 do not necessarily have to be divided for each stage.

[First Embodiment]
Hereinafter, the microchannel heat exchanger 1 according to the first embodiment will be described with reference to FIGS. 1 to 5.
As described above, the microchannel heat exchanger 1 includes the stirring sections 40 for stirring the refrigerant in the upstream headers 21 and 22.
FIG. 4 shows the first upstream header 21 and the stirring section 40. Hereinafter, the first upstream header 21 and the stirring section 40 corresponding to the first refrigerant will be described as an example, but the same applies to the second upstream header 22 and the stirring section 40 corresponding to the second refrigerant.

  The refrigerant flowing through the refrigerant circuit 80 contains foreign matter 9 such as iron powder caused by abrasion of a member made of an iron alloy such as a compressor and copper powder generated by flaring at the time of construction of the refrigerant pipe 5. ing. The particle size of the foreign material 9 such as iron powder is at most about 150 μm, which is fine. Therefore, even if a strainer (not shown) for capturing the foreign matter 9 in the refrigerant is provided in the refrigerant pipe 5 upstream of the microchannel heat exchanger 1, the fine foreign matter 9 that has passed through the strainer is not removed from the upstream header 21. , 22.

  When the flow rate of the refrigerant flowing from the refrigerant pipe 5 decreases inside the upstream headers 21 and 22, the influence of the refrigerant flow inside the upstream headers 21 and 22 is small, and the foreign matter 9 mixed in the refrigerant attracts the foreign matter 9 between the foreign substances 9. Easily aggregates. In order to prevent the microchannel 100 from being clogged by the condensed foreign matter 9, the foreign matter 9 is dispersed by stirring the refrigerant by the stirring unit 40 provided in the upstream headers 21 and 22.

The stirring section 40 gives a flow to the refrigerant, and disperses the foreign matter 9 in the refrigerant by the energy of the flow. Due to the action of the stirrer 40, even if the foreign substances 9 aggregate inside the upstream headers 21 and 22, the foreign substances 9 are subdivided.
In this specification, the term "stirring" is used in the sense of giving a flow to a liquid, wet vapor, or gas-phase fluid or changing the state of the fluid flow.

  By stirring, the refrigerant and the foreign substances 9 mixed in the refrigerant can be made uniform. From this viewpoint, it can be said that stirring produces the same effect as "mixing" for homogenizing two objects.

In order to disperse the foreign material 9, the stirring unit 40 can include a stirring blade that rotates to give a flow to the refrigerant, a stationary member that changes the state of the flow of the refrigerant based on the form, and the like.
The stirring unit 40 of the present embodiment includes the latter stationary member 41. The agitating section 40 of the present embodiment includes only the stationary member 41 and does not include a movable portion. The stationary member 41 is fixed to the upstream header 21 and acts on the refrigerant in a stationary state.

The stationary member 41 is installed inside the upstream header 21 and faces the end face 10A of the heat exchanger body 10 in which the openings of the microchannels 100 are arranged.
The stationary member 41 is surrounded by the lower wall 211, the upper wall 212, and the side wall 213 (FIG. 1) of the upstream header 21.
The stationary member 41 can be made of an appropriate material such as a metal material or a resin material as long as the material is compatible with the refrigerant.

  The first upstream header 21 and the second upstream header 22 are arranged in the same manner as the first upstream header 21 and the second upstream header 22 in order to install the stirrer 40 while securing the necessary flow path cross-sectional area and volume for the first upstream header 21 and the second upstream header 22. As shown in FIG. 1, they are arranged at positions separated from each other.

  The first microchannel group 101 extends linearly from the entrance to the exit of the microchannel 100. The first upstream header 21 is located on the extension line X of the first microchannel group 101 on the entrance side of the first microchannel group 101. The first downstream header 31 is located on an extension line X of the first micro channel group 101 on the exit side of the first micro channel group 101.

The second microchannel group 102 is bent at the entrance side and the exit side of the microchannel 100 with respect to the section 102M extending in parallel with the first microchannel group 101. The inlet and outlet of the second group of microchannels 102 are open on the side surface of the heat exchanger body 10.
Therefore, the second upstream header 22 communicating with the entrance of the second microchannel group 102 is located at a position outside the extension line X of the first microchannel group 101. The same applies to the second downstream header 32 communicating with the outlet of the second microchannel group 102.

  The second microchannel group 102 of the present embodiment is bent in opposite directions on the entrance side and the exit side with respect to the intermediate section 102M. For this reason, the second upstream header 22 is arranged on one side in the width direction of the heat exchanger body 10, whereas the second downstream header 32 is arranged on the other side in the width direction of the heat exchanger body 10. .

  Not limited to this embodiment, the second microchannel group 102 may be bent in the same direction on the inlet side and the outlet side. In that case, the second upstream header 22 and the second downstream header 32 are arranged on the same side in the width direction of the heat exchanger body 10.

In the case of the parallel flow type or the counter flow type, typically, both the first upstream header 21 and the second upstream header 22 are arranged so as to be located on the extension line X. The arrangement of the first upstream header 21 and the second upstream header 22 in the present embodiment is different from the typical example. In a typical example, the first upstream header 21 and the second upstream header 22 are integrated, whereas the first upstream header 21 and the second upstream header 22 in the present embodiment are separated from each other, and have different positions. I have.
Then, the member of the stirring section 40 can be easily installed inside the first and second upstream headers 21 and 22. If the first upstream header 21 and the second upstream header 22 are separated from each other, the position of the stirrer 40 does not interfere, and even if the amount occupied by the installation of the stirrer 40 is taken into consideration, each of the headers 21 and 22 is This is because a predetermined flow path cross-sectional area and volume required inside can be easily secured.
Therefore, according to the present embodiment in which the position of the first upstream header 21 and the position of the second upstream header 22 are separated, the stirrer 40 is installed, and the size and shape of the members of the stirrer 40 are reduced. The degree of freedom is improved.

  As shown in FIG. 5, the stationary member 41 according to the present embodiment has a configuration in which an appropriate number of elements 411 twisted around a predetermined axis A are connected in the direction of the axis A. Hereinafter, the upstream side of the refrigerant flow is referred to as “front”, and the downstream side is referred to as “rear”.

Each element 411 is configured in a shape in which a rectangular plate-like member is twisted by 180 °. Elements 411 that are adjacent in the direction of axis A are 90 ° shifted from one another about axis A. The rear end 411B of the element 411 and the front end 411A of the following element 411 are connected in a state of being orthogonal.
The stationary member 41 is preferably arranged on the header 21 such that the direction of the flow of the refrigerant in the installed header 21 matches the axis A.
As the stationary member 41 in which the plurality of elements 411 are continuous, for example, a “spiral type” “static mixer” available from Mercury Supply Systems Co., Ltd. can be used.

As shown in FIG. 4, the refrigerant introduced into the upstream header 21 through the refrigerant pipe 5 flows between the introduction part 201 and the stirring part 40, and further flows into the stirring part 40.
The behavior of the refrigerant flowing into the agitator 40 and flowing between the stationary member 41 and the wall of the upstream header 21 toward the heat exchanger body 10 shown in FIG. 5 will be described.
The refrigerant flowing into the stirring section 40 is divided by the front end 411A of the element 411 of the stationary member 41 (FIG. 5), and further twisted by being guided by the surface of the element 411, from the front end 411A to the rear end 411B of the element 411. While rotating in the direction indicated by the arrow toward, between the surface of the element 411 and the wall of the upstream header 21. When the refrigerant flows into the next element 411, the twisting direction of the element 411 changes, so that the direction in which the refrigerant rotates from the front end 411A toward the rear end 411B (the direction indicated by the arrow) also changes. An inertial force accompanying the change in the rotation direction is applied to the refrigerant.
Each operation of dividing, turning, and changing the rotation direction with respect to the flow of the refrigerant is repeated by the plurality of elements 411, and the refrigerant flowing into the stirring unit 40 is sufficiently stirred. The division of the flow of the refrigerant, the turning, and the change in the rotation direction referred to here correspond to the change in the flow state of the refrigerant. That is, the stationary member 41 stirs the refrigerant by changing the flow state of the refrigerant.

  Since the flow velocity of the refrigerant is small inside the upstream header 21, the stationary member 41 can sufficiently change the state of the refrigerant flow without being substantially affected by the refrigerant flow before flowing into the stationary member 41. . In addition, since the flow velocity of the refrigerant is small inside the upstream header 21, the refrigerant flows into the microchannel 100 smoothly without an excessive pressure loss of the refrigerant when passing through the stationary member 41.

  Even if the foreign matter 9 in the refrigerant flowing into the upstream header 21 is agglomerated inside the upstream header 21, the foreign matter 9 is dispersed in the refrigerant by being stirred in the process of flowing through the agitating section 40. Therefore, it is possible to prevent the opening of the microchannel 100 from being blocked by the aggregated foreign matter 9.

  Assuming that the stirring section 40 is not provided in the upstream header 21, the foreign matter 9 in the refrigerant introduced into the upstream headers 21 and 22 from the refrigerant pipe 5 is directed toward the heat exchanger body 10 together with the refrigerant while coagulating. And gather at the opening of the microchannel 100 having a small diameter. When the foreign matter 9 adheres to the vicinity of the opening of the microchannel 100, the foreign matter 9 aggregates also to the foreign matter 9 attached to the vicinity of the opening. Therefore, the aggregation of the foreign matter 9 is promoted and the microchannel 100 may be closed. is there.

  According to the present embodiment in which the upstream headers 21 and 22 are provided with the stirrer 40, even if the foreign matter 9 in the refrigerant aggregates inside the upstream headers 21 and 22, the foreign matter 9 is dispersed by the stirrer 40, The foreign matter 9 can be prevented from reaching the microchannel 100 in a state of an aggregate. Then, aggregation of the foreign matter 9 at the opening of the microchannel 100 can be suppressed, so that even if the diameter of the microchannel 100 is small, it is possible to prevent the microchannel 100 from being blocked.

  Since the stirring unit 40 is disposed near the opening of the microchannel 100, the foreign substances 9 in the refrigerant flowing out of the stirring unit 40 can be prevented from reaggregating, and the blocking of the microchannel 100 can be more reliably prevented. .

  The agitating section 40 of the present embodiment is composed of only the stationary member 41 and does not include a movable portion, so that the movable portion is unlikely to be damaged or broken. Also, no power is required to drive the movable parts. Therefore, the reliability of the microchannel heat exchanger 1 and the refrigerant system including the same can be ensured, and the operating cost of the refrigerant system can be suppressed.

Instead of the stationary member 41 shown in FIG. 5, a stationary member 42 shown in FIG. 6 can be used.
The stationary member 42 also stirs the refrigerant by acting on the refrigerant in a state of being stationary and fixed to the upstream header 21.

As shown in FIG. 6, the stationary member 42 is configured in a form in which an appropriate number of elements 420 formed of baffle plates (baffle plates) are connected in the axial direction of the shaft portion 42S. These elements 420 and the shaft 42S are integrated.
Element 420 is comprised of three baffle plates 421,422,423. Each of these baffle plates 421, 422, and 423 is configured to have a shape obtained by halving the elliptical shape along the long axis, and a straight edge 42E along the long axis is arranged toward the shaft portion 42S. ing.

The baffle plates 421 and 422 are arranged so as to sandwich the shaft 42S from both sides and to be inclined in the opposite direction to the shaft 42S. The baffle plates 421 of each element 420 are arranged in parallel with each other, and the same is true of the baffle plates 422 and 423. The baffle plate 423 connects between the rear end 422B of the baffle plate 422 and the front end 422A of the subsequent baffle plate 422.
As the stationary member 42, for example, a “static tube type” “static mixer” available from Mercury Supply Systems Co., Ltd. can be used.

  According to the stationary member 42 in which the semi-elliptical baffle plates 421, 422, and 423 are combined, the refrigerant flowing into the stationary member 42 is guided by the plates 421, 422, and 423 in a direction intersecting the shaft portion 42S, and the It flows while moving between plates over 42E. When moving between the plates, the directions of inclination of the respective plates with respect to the shaft portions 42S are different, so that the direction of the flow of the refrigerant rapidly changes. Such a change in the flow direction of the refrigerant is repeated by the plurality of elements 420, and the refrigerant flowing into the stationary member 42 is sufficiently stirred.

  In addition, as long as the state of the flow of the refrigerant can be changed, a stationary member having an appropriate form can be used.

[Modification of First Embodiment]
In the example shown in FIGS. 7A and 7B, an area in which the stirring section 40 inside the upstream header 21 is arranged is partitioned into an appropriate number of sections 53 by walls 51 and 52. Here, nine partitions 53 are provided inside the upstream header 21 by combining the two walls 51 and the two walls 52 in a lattice shape. It is preferable that these sections 53 are arranged over the entire flow path cross-sectional area of the upstream header 21.

  The stationary member 41 (FIG. 5) or the stationary member 42 (FIG. 6) described above is installed in each of the plurality of sections 53. The stirring section 40 corresponds to a set of the stationary members 41 arranged in the section 53 or a set of the stationary members 42 arranged in the section 53. In the stirring section 40, the stationary member 41 and the stationary member 42 may be mixed.

  Like the first upstream header 21, the second upstream header 22 is preferably provided with a plurality of sections 53 in each of which the stationary member 41 or the stationary member 42 is arranged.

Hereinafter, a case where the stationary member 41 is disposed in the section 53 will be described as an example.
The stationary member 41 arranged in the section 53 is surrounded by the walls 51 and 52 and the wall of the upstream header 21. An appropriate clearance is set between the outer peripheral portion of the stationary member 41 and the surrounding wall.

When the stationary member 41 is arranged in the section 53 formed by the walls 51 and 52, a flow path suitable for stirring can be provided around the stationary member 41. The wall surrounding the stationary member 41 maintains the flow of the refrigerant in the vicinity of the stationary member 41, and sufficiently exerts the stirring action of the stationary member 41 on the refrigerant, such as splitting, turning, and changing the rotation direction of the refrigerant flow. .
According to the agitating section 40 composed of a collection of the stationary members 41 arranged in the section 53, the refrigerant can be more sufficiently agitated by each stationary member 41, and the dispersion of the foreign matter 9 can be promoted.
The same applies when the stationary member 42 is used instead of the stationary member 41.

[Second embodiment]
Next, a microchannel heat exchanger 2 according to a second embodiment of the present invention will be described with reference to FIG. Hereinafter, the description will focus on matters that differ from the first embodiment. The same components as those in the first embodiment are denoted by the same reference numerals.

The microchannel heat exchanger 2 according to the second embodiment includes a stirrer 60 that stirs a refrigerant in each of the first upstream header 21 and the second upstream header 22.
The stirring device 60 includes a rotating member 61 that is rotated, and a driving unit 62 that drives the rotating member 61. The rotating member 61 has a shaft 611 rotated by a driving unit such as a motor, and a blade member 612 (blade) integrated with the shaft 611.
Such a stirring device 60 corresponds to a so-called stirring blade. Various stirring blades such as a turbine blade, a paddle blade, and a propeller blade can be used for the stirring device 60.
By switching the rotation direction of the rotating member 61 between the forward rotation and the reverse rotation by the driving unit 62, the inertia force acts on the refrigerant, and the stirring efficiency can be improved.

  Further, the second embodiment discloses a counter-flow type configuration. The first microchannel group 101 and the second microchannel group 102 are configured in the same manner as in the first embodiment of the parallel flow type, but differ in the direction in which the refrigerant flows. In the second embodiment, a section in which the first and second microchannel groups 101 and 102 extend in parallel includes a first refrigerant having a flow direction indicated by a dotted line and a second refrigerant having a flow direction indicated by a solid line. At 102M, they flow in opposite directions.

  Since the flow direction of the first refrigerant is opposite to that of the first embodiment, in the second embodiment, the positions of the upstream header 21 and the downstream header 31 of the first refrigerant are the same as those in the first embodiment (FIG. It is the opposite of 1).

  Also in the counter-flow type microchannel heat exchanger 2, the position of the first upstream header 21 and the position of the second upstream header 22 are separated from each other, as in the first embodiment. The stirrer 60 can be easily installed in each of the upstream headers 21 and 22 while securing the necessary flow path cross-sectional area and volume for each of the upstream headers 22.

In the second embodiment, the coolant is agitated by rotating the rotating member 61 at an appropriate speed by the drive unit 62 of the agitating device 60. The rotating blade member 612 forcibly gives a flow to the refrigerant flowing into the upstream header 21. By the blade member 612, the refrigerant is given at least a flow of swirling around the shaft portion 611. Depending on the shape of the blade member 612, a flow in the axial direction of the shaft portion 611 and a flow from the shaft portion 611 to the outside in the radial direction are also given. Even when a baffle plate is installed to increase the efficiency of stirring, an axial flow is given to the refrigerant. The shear force mainly acts on the refrigerant due to such a flow, whereby the foreign matter 9 is dispersed.
Since the stirrer 60 is disposed near the heat exchanger body 10 where the openings of the microchannels 100 are arranged, the refrigerant immediately after being discharged from the stirrer 60 flows into the microchannel 100 without reaggregation.

  According to the second embodiment as well, by dispersing the foreign matter 9 by the stirring device 60, the aggregation of the foreign matter 9 at the opening of the microchannel 100 can be suppressed, and the microchannel 100 can be prevented from being blocked.

[Third embodiment]
FIG. 9A shows a cross-flow type microchannel heat exchanger 3.
In the microchannel heat exchanger 3, the direction in which the first refrigerant flows through the first microchannel group 101 (dashed arrow) is orthogonal to the direction in which the second refrigerant flows through the second microchannel group 102 (solid arrow). I do.
The first upstream header 21 corresponding to the first refrigerant is located on the extension line X1 of the first microchannel group 101 extending linearly. The same applies to the first downstream header 31.
The second upstream header 22 corresponding to the second refrigerant is located on the extension line X2 of the second microchannel group 102 extending linearly. The same applies to the second downstream header 32.

As shown in FIG. 9B, both the first upstream header 21 and the second upstream header 22 are provided with a stirring unit 40.
In the cross-flow type, since the first upstream header 21 and the second upstream header 22 are separated from each other, the stirring section 40 can be easily formed while securing the necessary flow path cross-sectional area and volume in the upstream headers 21 and 22. At the headers 21 and 22.

  In addition to the above, the configuration described in the above embodiment can be selected or changed to another configuration as appropriate without departing from the gist of the present invention.

  The heat exchanger body 10 of the microchannel heat exchanger is divided in the length direction of the microchannel 100, and the upstream portion of the heat exchanger body 10 and the downstream portion of the heat exchanger body 10 are separated. There may be an intermediate header to relay. In that case, the intermediate header corresponds to an upstream header in which the refrigerant is introduced from the upstream portion of the heat exchanger body 10 and the refrigerant flows into the microchannel 100 formed in the downstream portion of the heat exchanger body 10. I do. By providing the stirrer 40 or the stirrer 60 on the intermediate header, it is possible to prevent the microchannel 100 from being blocked by the foreign matter 9.

1-3 Micro channel heat exchanger 5 Refrigerant piping 8 Refrigeration cycle device 9 Foreign matter 10 Heat exchanger main body 10A End face 11 Metal plates 11A, 11B Grooves 21, 22 Upstream header 31, 32 Downstream header 40 Stirrer 41, 42 Stationary member 42E Edge 42S Shaft 51, 52 Wall 53 Section 60 Stirring device (stirring unit)
61 Rotating member 611 Shaft portion 612 Blade member 62 Drive unit 80 Refrigerant circuit 81 Compressor 82 First heat exchanger 83 Decompression unit 84 Second heat exchanger 100 Microchannel 101 First microchannel group 102 Second microchannel group 102M Section 201, 202 Introducing part 211 Lower wall 212 Upper wall 213 Side wall 301, 302 Discharge part 411 Element 411A Front end 411B Rear end 420 Element 421, 422, 423 Baffle plate 422A Front end 422B Rear end A Axis X, X1, X2 Extension

Claims (8)

A heat exchanger body having a plurality of microchannels;
An upstream header communicating with the plurality of microchannels and introducing a fluid;
A stirrer that stirs the fluid that has flowed into the upstream header,
A microchannel heat exchanger characterized by the above-mentioned. The stirring unit has a stationary member configured to change a state of the flow of the fluid,
The microchannel heat exchanger according to claim 1. The area where the agitating section is arranged in the upstream header is partitioned into a plurality of sections,
In each of the plurality of sections, the stationary member is disposed,
The microchannel heat exchanger according to claim 2. The stirring unit is
A rotating member to be rotated,
A driving unit for driving the rotating member,
The microchannel heat exchanger according to claim 1. The stirring unit is
Inside the upstream header, disposed near the opening of the microchannel,
The microchannel heat exchanger according to any one of claims 1 to 4. The plurality of micro channels are
A first microchannel group and a second microchannel group,
The fluid flows in the first micro-channel group and the second micro-channel group in a state of parallel flow or counter flow,
A first upstream header, which communicates with the first group of microchannels and into which the fluid is introduced,
Located on an extension of the first microchannel group extending linearly,
A second upstream header that communicates with the second group of microchannels and into which the fluid is introduced,
At a position off the extension line,
The microchannel heat exchanger according to any one of claims 1 to 5. The plurality of micro channels are
A first microchannel group and a second microchannel group,
The direction of the fluid flowing through the first group of microchannels is orthogonal to the direction of the fluid flowing through the second group of microchannels,
A first upstream header, which communicates with the first group of microchannels and into which the fluid is introduced,
Located on an extension of the first microchannel group extending linearly,
A second upstream header that communicates with the second group of microchannels and into which the fluid is introduced,
Located on an extension of the second microchannel group extending linearly,
The microchannel heat exchanger according to any one of claims 1 to 5. A microchannel heat exchanger according to any one of claims 1 to 6,
A compressor that compresses a refrigerant that is the fluid,
A first heat exchanger for exchanging heat between the refrigerant and a heat source,
A pressure reducing unit that reduces the pressure of the refrigerant,
A second heat exchanger for exchanging heat between the refrigerant and a heat load, and a refrigerant circuit including:
The microchannel heat exchanger,
A first microchannel group and a second microchannel group,
Heat exchange between a first refrigerant flowing through the first microchannel group and a second refrigerant flowing through the second microchannel group;
A refrigeration cycle device characterized by the above-mentioned.

Images