CN116255843A - A kind of heat exchanger and refrigeration system - Google Patents

Abstract

The present application relates to a heat exchanger and a refrigeration system. The heat exchanger includes: a header, at least including a first header and a second header, the first header is provided with a refrigerant inlet, and the second header A refrigerant outlet is provided; the heat exchange tube row includes at least a first heat exchange tube row and a second heat exchange tube row; wherein, along the axial direction of the first header, the first heat exchange tube row includes a plurality of The heat exchange tubes connected by the headers, so that the heat exchange tubes of the first heat exchange tube row are connected in parallel, and along the axial direction of the second header, the second heat exchange tube row includes a plurality of tubes communicating with the second header heat exchange tubes so that the heat exchange tubes of the second heat exchange tube row are connected in parallel; along the direction from the refrigerant inlet to the refrigerant outlet, the cross-sectional area of the heat exchange tubes of each heat exchange tube row decreases or increases. The embodiment of the present application can reduce the overall size of the heat exchanger and reduce the cost of the heat exchanger while increasing the total heat exchange capacity of the heat exchanger and satisfying the heat exchange demand of each position.

Description

A kind of heat exchanger and refrigeration system

technical field

The present application relates to the technical field of refrigeration equipment, in particular to a heat exchanger and a refrigeration system.

Background technique

The heat exchanger can be used in refrigeration systems such as refrigerators and air conditioners to achieve heat exchange. The heat exchanger includes multiple heat exchange tubes, and the refrigerant flows in the heat exchanger. The size of each heat exchange tube determines the size of the heat exchanger. The heat transfer capacity of the heat exchanger determines the cooling capacity of the refrigeration system. Therefore, in order to improve the refrigeration capacity of the refrigeration system, it is necessary to increase the heat transfer capacity of the heat exchanger, that is, it is necessary to increase the heat transfer area of the heat exchange tube, and increasing the heat transfer area of the heat exchange tube will result in a larger volume and weight of the heat exchanger. is too big.

Contents of the invention

The present application provides a heat exchanger and a refrigeration system, the heat exchanger has a relatively high heat exchange capacity and is small in size.

The first aspect of the embodiment of the present application provides a heat exchanger, the heat exchanger comprising:

A header, the header includes at least a first header and a second header, the first header is provided with a refrigerant inlet, and the second header is provided with a refrigerant outlet;

A heat exchange tube row, the heat exchange tube row at least including a first heat exchange tube row and a second heat exchange tube row;

Wherein, along the axial direction of the first header, the first heat exchange tube row includes a plurality of heat exchange tubes communicating with the first header, so that the first heat exchange tube row The heat exchange tubes are connected in parallel, and along the axial direction of the second header, the second heat exchange tube row includes a plurality of heat exchange tubes communicating with the second header, so that the first The heat exchange tubes of the two heat exchange tube rows are connected in parallel;

Along the direction from the refrigerant inlet to the refrigerant outlet, the cross-sectional area of the heat exchange tubes of each heat exchange tube row decreases or increases.

In a possible design, when the heat exchanger is a condenser, along the direction from the refrigerant inlet to the refrigerant outlet, the cross-sectional area of the heat exchange tubes in each heat exchange tube row decreases gradually. Small;

When the heat exchanger is an evaporator, along the direction from the refrigerant inlet to the refrigerant outlet, the cross-sectional area of the heat exchange tubes in each heat exchange tube row increases gradually.

In a possible design, along the axial direction of the first header, the first header is provided with a plurality of first openings, and the first openings are used to communicate with the first heat exchange tubes. Each of the heat exchange tubes in the row is connected;

Along the axial direction of the second header, the second header is provided with a plurality of second openings, and the second openings are used to communicate with the heat exchange tubes of the second heat exchange tube row. connect;

Each of the first openings has the same size, and each of the second openings has the same size;

When the heat exchanger is a condenser, the size of the first opening is larger than the size of the second opening; when the heat exchanger is an evaporator, the size of the first opening is smaller than that of the second opening size. In a possible design, the heat exchange tube is a flat tube, and the first opening and the second opening are oblong holes;

The length direction of the first opening is perpendicular to the axial direction of the first header;

The length direction of the second opening is perpendicular to the axial direction of the second header.

In a possible design, the header further includes a plurality of third headers, and the third headers are connected to the heat exchange tubes adjacent to the heat exchange tube row, so that the refrigerant can Flow between adjacent heat exchange tube rows.

In a possible design, the heat exchange tubes of the heat exchange tube row are respectively connected to different third headers.

In a possible design, both ends of the third header along the axial direction are blocked, and the third header is provided with two third openings, and the two third openings are arranged along the Axial arrangement of the third header.

In a possible design, both ends of the third header in the axial direction are blocked, and the third header is provided with more than two third openings, and each of the third openings is the axial arrangement of the third header;

The third header further includes a baffle, and the baffle divides the third header into two or more flow spaces, and there are two third openings in the flow spaces.

In a possible design, when the heat exchanger is a condenser, the size of the third opening decreases gradually along the direction from the refrigerant inlet to the refrigerant outlet;

When the heat exchanger is an evaporator, the size of the third opening increases gradually along a direction from the refrigerant inlet to the refrigerant outlet.

In a possible design, the length direction of the third opening is parallel to the axial direction of the third header.

In a possible design, when the heat exchanger is an evaporator, the inner diameter of the first header is smaller than the inner diameter of the second header;

When the heat exchanger is a condenser, the inner diameter of the first header is larger than the inner diameter of the second header;

The inner diameters of each of the third headers are equal.

In a possible design, the heat exchanger further includes fins connected to adjacent heat exchange tubes of each heat exchange tube row;

When the heat exchanger is an evaporator, the density of the fins decreases along a direction from the refrigerant inlet to the refrigerant outlet. The second aspect of the embodiment of the present application provides a refrigeration system, and the refrigeration system includes:

compressor;

a heat exchanger in communication with the compressor;

Wherein, the heat exchanger is the heat exchanger described above.

In the embodiment of the present application, by arranging a plurality of parallel heat exchange tubes, and along the direction from the refrigerant inlet to the refrigerant outlet, the cross-sectional area of the heat exchange tubes of each heat exchange tube row gradually decreases or increases, which can improve the While the total heat exchange capacity of the heat exchanger meets the heat exchange demand of each position, the overall size of the heat exchanger is reduced, and the cost of the heat exchanger is reduced.

It is to be understood that both the foregoing general description and the following detailed description are exemplary only and are not restrictive of the application.

Description of drawings

Fig. 1 is a schematic structural view of a heat exchanger provided by the present application in a first specific embodiment;

Fig. 2 is the structural representation of the heat exchanger provided in the present application in the second specific embodiment;

Fig. 3 is the top view of Fig. 2;

Fig. 4 is a structural schematic diagram of the connection between the first header (or the second header) and the heat exchange tube in Fig. 2;

Fig. 5 is a top view of the first header (or the second header) in Fig. 4;

Fig. 6 is a schematic structural diagram of the connection between the third header and the heat exchange tube in Fig. 2;

Fig. 7 is the partial enlarged view of part I in Fig. 6;

Fig. 8 is a schematic structural view of the third header in Fig. 2 in the first specific embodiment;

Fig. 9 is the front view of Fig. 8;

Fig. 10 is a schematic structural view of the third header in Fig. 2 in a second specific embodiment;

Figure 11 is a front view of Figure 10;

FIG. 12 is a schematic structural diagram of a third header in FIG. 2 .

Reference signs:

11 - the first header;

111 - first opening;

112-refrigerant inlet;

12 - the second header;

121 - second opening;

122-refrigerant outlet;

13 - the third header;

131 - third opening;

132 - clapboard;

21 - the first heat exchange tube row;

22 - the second heat exchange tube row;

23 - the third heat exchange tube row;

24 - heat exchange tube;

241-microchannel;

242-connection part;

3 - fins.

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the application and together with the description serve to explain the principles of the application.

Detailed ways

In order to better understand the technical solutions of the present application, the embodiments of the present application will be described in detail below in conjunction with the accompanying drawings.

It should be clear that the described embodiments are only some of the embodiments of the present application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of this application.

Terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms "a", "said" and "the" used in the embodiments of this application and the appended claims are also intended to include plural forms unless the context clearly indicates otherwise.

It should be understood that the term "and/or" used herein is only an association relationship describing associated objects, which means that there may be three relationships, for example, A and/or B, which may mean that A exists alone, and A and B exist simultaneously. B, there are three situations of B alone. In addition, the character "/" in this article generally indicates that the contextual objects are an "or" relationship.

It should be noted that the orientation words such as "up", "down", "left", and "right" described in the embodiments of the present application are described from the angles shown in the drawings, and should not be interpreted as limiting the implementation of the present application. Example limitations. Furthermore, in this context, it also needs to be understood that when it is mentioned that an element is connected "on" or "under" another element, it can not only be directly connected "on" or "under" another element, but can also To be indirectly connected "on" or "under" another element through an intervening element.

The heat exchanger can be used in refrigeration systems such as refrigerators and air conditioners. The refrigeration system can include compressors, heat exchangers (including evaporators and condensers), filters, expansion valves and other components. And high-pressure, low-temperature and high-temperature conversion devices are the power source to promote the circulation of refrigerant in the refrigeration system; the condenser belongs to the heat exchanger, which is used to transfer the heat of the high-temperature and high-pressure refrigerant from the compressor to the air around the condenser, thereby Condensing high-temperature and high-pressure gaseous refrigerant into high-temperature and high-pressure liquid refrigerant; the refrigerant discharged from the condenser is filtered through a filter, then enters the expansion valve, and the liquid refrigerant is throttled to convert it into a low-pressure liquid refrigerant; the evaporator is also a replacement The low-pressure liquid refrigerant absorbs heat in the evaporator to realize refrigeration, and converts the liquid refrigerant into a gaseous state to complete a refrigeration cycle.

Therefore, in the above-mentioned refrigeration system, there is a phase change of the refrigerant in the heat exchanger (evaporator and condenser), for example, in the evaporator, the refrigerant changes from liquid to gas, and in the condenser, the refrigerant changes from gas to liquid , taking the evaporator as an example, at the position close to the refrigerant inlet, the content of liquid refrigerant is higher at this position, the density of liquid refrigerant is higher, and the space required for the same mass of refrigerant in liquid state is much smaller than that of gaseous state. Therefore, when evaporating At the front end of the refrigerant inlet of the device, the heat exchange volume and heat exchange area required by the heat exchange tube are small; while at the position near the refrigerant outlet, most of the refrigerant has been transformed into a gaseous state, and the content of liquid refrigerant at this position is low. The latent heat of vaporization of the refrigerant during heat exchange is the main source used to cool the environment outside the heat exchange tube. The heat absorbed by the vaporization of the refrigerant is large, and the gaseous refrigerant has a small density and occupies a large space. Therefore, the evaporator is located near the refrigerant outlet. , the heat exchange area required by the heat exchange tube is relatively large.

In order to increase the conversion rate of liquid refrigerant into gaseous refrigerant in the evaporator, it is necessary to ensure that the heat exchange tubes in the heat exchanger have sufficient heat exchange area. The large area can make the refrigerant have a high conversion rate, but the large area of the heat exchange tube leads to a large area of the evaporator, which is not conducive to the miniaturization of refrigeration systems such as refrigerators and air conditioners. When the heat exchange area of the heat exchange tube is reduced, the heat exchange capacity of the heat exchanger is low, resulting in a low cooling capacity of the refrigeration system, which cannot meet the needs of users.

Therefore, in order to increase the heat exchange capacity of the heat exchanger to increase the refrigeration capacity of the refrigeration system, the heat exchange area of the heat exchange tube can be increased, specifically, it can be achieved by increasing the diameter of the heat exchange tube or the length of the heat exchange tube , However, increasing the diameter and length of the heat exchange tube will lead to excessive volume and weight of the heat exchanger.

In order to solve the above technical problems, embodiments of the present application provide a refrigeration system and a heat exchanger. The heat exchanger may specifically be an evaporator or a condenser. In this paper, the heat exchanger is used as an evaporator as an example for introduction.

As shown in Figures 1 and 2, the heat exchanger includes a header, the header includes at least a first header 11 and a second header 12, the first header 11 is provided with a refrigerant inlet 112, The second header 12 is provided with a refrigerant outlet 122, the refrigerant inlet 112 is used to pass the refrigerant into the heat exchanger, and the refrigerant outlet 122 is used to discharge the refrigerant after heat exchange from the heat exchanger, for example, the evaporator The refrigerant inlet 112 is used to pass liquid refrigerant into the evaporator, and the refrigerant outlet 122 is used to discharge gaseous refrigerant out of the evaporator. Wherein, the evaporator can be an air-cooled evaporator, that is, in the evaporator, the gas with a higher temperature (such as air) exchanges heat with the refrigerant in the evaporator, and the refrigerant absorbs the heat in the environment outside the heat exchange tube to reduce the temperature of the environment. Temperature, the refrigerant in the heat exchange tube changes from liquid to gaseous, that is, the low-temperature and low-pressure liquid refrigerant in the evaporator is transformed into a low-temperature and low-pressure gaseous refrigerant. Moreover, in the evaporator, the flow direction of the refrigerant is approximately perpendicular to the flow direction of the air, thereby realizing convective heat exchange.

The heat exchanger also includes a plurality of heat exchange tube rows, the heat exchange tube row at least includes a first heat exchange tube row 21 and a second heat exchange tube row 22, and the first heat exchange tube row 21 and the second heat exchange tube row The tube rows 22 each include a plurality of heat exchange tubes 24, and at the same time, along the axial direction of the first header 11, each heat exchange tube 24 of the first heat exchange tube row 21 communicates with the first header 11, thereby The heat exchange tubes 24 of the first heat exchange tube row 21 are connected in parallel; similarly, along the axial direction of the second header 12, each heat exchange tube 24 of the second heat exchange tube row 22 is connected to the second header The flow tubes 12 are connected, so that the heat exchange tubes 24 of the second heat exchange tube row 22 are connected in parallel.

Therefore, in this embodiment, the first header 11 is used to pass the refrigerant into each heat exchange tube 24, and the second header 12 is used to discharge the refrigerant from each heat exchange tube 24. When the heat exchanger includes a plurality of heat exchange tubes 24 connected in parallel, the total heat exchange area of the heat exchange tubes 24 in the heat exchanger can be increased, and the length of each heat exchange tube 24 is small, and the refrigerant flows in each heat exchange tube 24 The resistance of the heat exchanger is small, so that the total length of the heat exchanger is small, which facilitates the miniaturization of the heat exchanger, improves the heat exchange capacity of the heat exchanger, and saves energy.

In addition, in the embodiment of the present application, along the direction L from the refrigerant inlet 112 to the refrigerant outlet 122 , the cross-sectional area of the heat exchange tubes 24 of each heat exchange tube row decreases or increases.

In the embodiment of the present application, the cross-sectional area of each heat exchange tube 24 in the heat exchanger changes, that is, the heat exchange area of each heat exchange tube 24 is different, so that the heat exchange can be reasonably adjusted according to the difference in the amount of heat exchange required at a specific position. The cross-sectional area of the tube 24 can reduce the cost while satisfying the heat transfer required by each position.

To sum up, in the embodiment of the present application, by setting a plurality of parallel heat exchange tubes 24 and setting the heat exchange tubes 24 to different cross-sectional areas, it is possible to improve the total heat exchange capacity of the heat exchanger and meet the heat exchange demand of each position. At the same time, the overall size of the heat exchanger is reduced, and the cost of the heat exchanger is reduced.

Specifically, when the heat exchanger is used as a condenser, along the direction L from the refrigerant inlet 112 to the refrigerant outlet 122, the cross-sectional area of the heat exchange tubes 24 of each heat exchange tube row decreases gradually, that is, when the heat exchanger is used as a condenser When the device is in operation, the cross-sectional area of the heat exchange tubes 24 of the first heat exchange tube row 21 near the refrigerant inlet 112 is greater than the cross-sectional area of the heat exchange tubes 24 of the second heat exchange tube row 22 near the refrigerant outlet 122 . When the heat exchanger is used as an evaporator, along the direction from the refrigerant inlet 112 to the refrigerant outlet 122, the cross-sectional area of the heat exchange tubes 24 of each heat exchange tube row increases gradually, that is, when the heat exchanger is used as an evaporator, close to The cross-sectional area of the heat exchange tubes 24 of the first heat exchange tube row 21 at the refrigerant inlet 112 is smaller than the cross-sectional area of the heat exchange tubes 24 of the second heat exchange tube row 22 near the refrigerant outlet 122 .

Taking the heat exchanger as an evaporator as an example, after the refrigerant enters the evaporator from the refrigerant inlet 112, it continuously undergoes phase change heat during the process of flowing in the heat exchange tube 24, and as the heat exchange proceeds, the heat exchange tube 24 The content of the gaseous refrigerant inside increases, and at the position close to the refrigerant outlet 122, almost all the liquid refrigerant is converted into gaseous refrigerant. Because the density of the gaseous refrigerant is small, the volume of the heat exchange tube 24 occupied is relatively large. At the position of the refrigerant outlet 122, the cross-sectional area of the heat exchange tube 24 is larger. Therefore, the installation method in the implementation of the present application can meet the demand for the amount of heat exchange of the refrigerant at each position, and can also meet the volume requirements of the refrigerant at each position. At the same time, it can also reduce the total heat exchange area of the heat exchanger, thereby saving costs. . The process when the heat exchanger is used as a condenser is the opposite, and will not be repeated here.

Specifically, as shown in FIG. 5 , along the axial direction of the first header 11, the first header 11 is provided with a plurality of first openings 111, and the first openings 111 are used for connecting with the first heat exchange tube row 21. Each heat exchange tube 24 is connected; similarly, along the axial direction of the second header 12, the second header 12 is provided with a plurality of second openings 121, and the second openings 121 are used to connect with the second heat exchange tube row 22 Each heat exchange tube 24 is connected.

Wherein, for the first header 11 , the sizes of the first openings 111 are the same, and for the second header 12 , the sizes of the second openings 121 are the same. And in the heat exchanger, the size of the second opening 121 is different from that of the first opening 111 . Specifically, when the heat exchanger is used as a condenser, the size of the first opening 111 is greater than the size of the second opening 121; when the heat exchanger is used as an evaporator, the size of the first opening 111 is smaller than the second opening 121 size of.

In this embodiment, by setting the first opening 111, the size of each heat exchange tube 24 connected to the first header 11 is the same, and by setting the second opening 121, each heat exchange tube 24 connected to the second header 12 The heat pipes 24 have the same size, so that the structures of the first header 11 and the second header 12 and the heat exchanger are simplified. At the same time, when the size of the second opening 121 is larger or smaller than the size of the first opening 111 , the size of the heat exchanger can be reduced while satisfying the heat exchange capacity of each position of the heat exchanger.

More specifically, as shown in FIG. 4 , the heat exchange tube 24 can be a flat tube, and the first opening 111 and the second opening 121 are both oblong holes, and the oblong holes can be easily matched with the flat tube, thereby realizing the first collection. The connection of the flow pipe 11 , the second header pipe 12 and the heat exchange pipe 24 . In addition, as shown in FIG. 5, the length direction of the first opening 111 is perpendicular to the axial direction of the first header 11, and the length direction of the second opening 121 is perpendicular to the axial direction of the second header 12. Therefore, the first The axial direction of the first header 11 and the axial direction of the heat exchange tubes 24 connected thereto are perpendicular to each other, and the axial direction of the second header 12 and the axial direction of the heat exchange tubes 24 connected thereto are perpendicular to each other, thus not only simplifying the first The structure of the first header 11 and the second header 12 can also reduce the overall size of the heat exchanger.

In this embodiment, the length direction of the first opening 111 represents the direction in which the size of the first opening 111 is the largest, and the length direction of the second opening 121 represents the direction in which the size of the first opening 121 is the largest. In addition, the length direction of the first opening 111 is perpendicular to the axial direction of the first header 11, which means that the two are approximately perpendicular, not strictly perpendicular. The length direction of the second opening 121 is perpendicular to the axial direction of the second header 12, which means that the two Or roughly vertical, not strictly vertical.

In addition, as shown in FIG. 4 , the first opening 111 and the refrigerant inlet 112 are disposed at different positions of the first header 11 , and the second opening 121 and the refrigerant outlet 122 are disposed at different positions of the second header 12 .

In a specific embodiment, as shown in Figure 1 and Figure 2, the heat exchanger may also include a plurality of third headers 13, the third headers 13 are used to connect adjacent heat exchange tube rows heat exchange tubes 24 so that the refrigerant can flow between adjacent rows of heat exchange tubes 24 .

In this embodiment, by setting the third header 13, the heat exchanger can include multiple rows of heat exchange tubes, and the refrigerant can flow between multiple rows of heat exchange tubes, thereby further improving the performance of the heat exchanger. Exchange heat and reduce the resistance of refrigerant flow.

Wherein, in the embodiment shown in Fig. 1 and Fig. 2, the heat exchanger includes four rows of heat exchange tube rows, which are the first heat exchange tube row 21 connected to the first header 11, and the second header tube row 21 respectively. The second heat exchange tube row 22 connected to the flow tube 12, the two rows of third heat exchange tube rows 23 located between the first heat exchange tube row 21 and the second heat exchange tube row 22, and the four rows of heat exchange tube rows along the The direction L from the refrigerant inlet 112 to the refrigerant outlet 122 can be arranged along the height direction of the heat exchanger. The heat pipe row 21 flows to the third heat exchange pipe row 23 through the third header 13, and flows to the second heat exchange pipe row 22, and finally is discharged from the refrigerant outlet 122 of the second header 12, thereby reducing the energy consumption.

Therefore, as shown in Figures 1 and 2, in this heat exchanger, the heat exchange tubes 24 in each heat exchange tube row are connected in parallel, and after being connected in parallel, each heat exchange tube row is connected in series, thereby realizing the cooling of the refrigerant. flow.

Specifically, as shown in FIG. 1 and FIG. 2 , each heat exchange tube 24 of the heat exchange tube row is respectively connected to a different third header 13 .

In this embodiment, the number of third headers 13 connected to each heat exchange tube row is the same as the number of heat exchange tubes 24 in each heat exchange tube row. Therefore, the refrigerant enters the heat exchanger from the first header 11. After the heat pipes 24, they flow independently in each heat exchange tube 24 and the third header 13, and the refrigerant in each heat exchange tube 24 will not mix with each other before entering the second header 12, thereby reducing the flow of the refrigerant. resistance.

Wherein, as shown in FIG. 1 and FIG. 2 , the axial direction of each third header 13 is parallel to the direction L from the refrigerant inlet 112 to the refrigerant outlet 122 , and the third headers 13 are parallel to each other. That is, in the heat exchanger, the axis of the third header 13 is along the vertical direction, so that the refrigerant can flow along the third header 13 under the action of gravity.

More specifically, the axial ends of the first header 11, the second header 12, and the third header 13 are blocked, and specifically can be blocked by a cover. Therefore, the first header 11 The refrigerant inside can only be discharged through the first opening 111 , the refrigerant in the second header 12 can only be discharged through the refrigerant outlet 122 , and the refrigerant in the third header 13 can only be discharged through the third opening 131 . Wherein, the third header 13 is provided with two third openings 131, the two third openings 131 are arranged along the axial direction of the third header 13, and the two third openings 131 are respectively connected to adjacent switches. The heat exchange tubes 24 of the heat pipe row.

As shown in FIG. 1 and FIG. 6 , the third header 13 is used to connect the heat exchange tubes 24 of adjacent heat exchange tube rows in series. Therefore, the third header 13 is provided with at least two third openings 131 , In the embodiment shown in Figure 8 and Figure 9, the third header 13 is provided with two third openings 131, at this time, the third header 13 can connect two adjacent heat exchange tube rows The heat exchange tube 24 , and the third header 13 only needs to be sealed at both ends in the axial direction, and there is no need to arrange other structures inside the third header 13 , thereby simplifying the structure of the third header 13 .

In another specific embodiment, as shown in FIG. 10 and FIG. 11, the third header 13 is provided with more than two third openings 131, and each third opening 131 The axial arrangement of the flow pipe 13, at the same time, the third header 13 also includes one or more partitions 132, the partition 132 divides the third header 13 into two or more flow spaces, There are two third openings 131 in the circulation space, and the two third openings 131 are used for connecting the heat exchange tubes 24 of adjacent heat exchange tube rows.

In this embodiment, when the third header 13 includes more than two third openings 131, the third header 13 can connect more than two rows of heat exchange tube rows, and by setting the separator 132, it can ensure that The refrigerant can enter the heat exchange tubes 24 of each row of heat exchange tubes to increase the heat exchange capacity of the heat exchanger and improve the utilization rate of the heat exchange tubes 24 .

Wherein, in the embodiment shown in Fig. 10 and Fig. 11, the third header 13 includes four third openings 131, and is provided with a partition 132, and the partition 132 divides the third header 13 The inner cavity is divided into two circulation spaces, and each circulation space is provided with two third openings 131 . Therefore, the third header 13 can be connected to four rows of heat exchange tube rows. In this embodiment, the number of third headers 13 in the heat exchanger can be reduced.

In the above embodiments, as shown in FIG. 12 , when the heat exchanger is used as an evaporator, the size of the third opening 131 gradually increases along the direction L from the refrigerant inlet 112 to the refrigerant outlet 122 . When the heat exchanger is used as a condenser (not shown in the figure), along the direction L from the refrigerant inlet 112 to the refrigerant outlet 122 , the size of the third opening 131 decreases gradually.

In this embodiment, since the third header 13 is connected to the heat exchange tubes 24 of different heat exchange tube rows, and the cross-sectional areas of the heat exchange tubes 24 of different heat exchange tube rows are different, therefore, the third header 13 of the same third header 13 The sizes of the three openings 131 are different so as to match with the corresponding heat exchange tubes 24, so as to improve the effective utilization rate of the heat exchange area of each heat exchange tube in the heat exchanger and reduce the overall size of the heat exchanger.

As shown in Figure 12, two rows of third headers 13 are arranged along the height direction (direction L from the refrigerant inlet 112 to the refrigerant outlet 122), and each row of third headers 13 includes three third headers 13. Each third header 13 is provided with two third openings 131 . When the heat exchanger is used as an evaporator, as shown in FIG. 12 , along the direction L from the refrigerant inlet 112 to the refrigerant outlet 122 , the size of the third opening 131 gradually increases. When the heat exchanger is used as a condenser (not shown in the figure), along the direction L from the refrigerant inlet 112 to the refrigerant outlet 122 , the size of the third opening 131 decreases gradually.

In addition, when the heat exchange tube 24 is a flat tube, the third opening 131 can specifically be an oblong hole structure, and as shown in FIGS. parallel to the direction, wherein the length direction of the third opening 131 is the direction where its largest dimension is located, and the length direction of the third opening 131 is parallel to the axial direction of the third header 13, which means that the two are roughly parallel, not Strictly parallel, and when the two are parallel, the interconnected third header 13 and the heat exchange tube 24 are perpendicular to each other, thereby reducing the overall size of the heat exchanger.

Specifically, as shown in Figures 1 and 2, when the heat exchanger is used as an evaporator, the inner diameter of the first header 11 is smaller than the inner diameter of the second header 12, and the inner diameter of each third header 13 equal inner diameter. When the heat exchanger is used as a condenser (not shown in the figure), the inner diameter of the first header 11 is larger than that of the second header 12 , and the inner diameters of the third headers 13 are the same.

In this embodiment, taking the heat exchanger as an evaporator as an example, when the inner diameter of the first header 11 is smaller than the inner diameter of the second header 12, the flow rate of the refrigerant in the first header 11 is relatively high, namely The flow velocity and pressure of the refrigerant just entering the third headers 13 are relatively high, so that the refrigerant can be promoted to enter the heat exchange tubes 24 of the first heat exchange tube row 21 to promote the flow of the refrigerant. When the inner diameters of the third headers 13 are equal, only the size of the third opening 131 of the third headers 13 of the heat exchanger is different, thereby simplifying the processing of the heat exchanger.

In the above embodiments, as shown in Figure 1 and Figure 2, in the heat exchanger, when the heat exchange tube 24 is a flat tube, its large surface (the end surface with the largest cross-sectional area) is along the vertical direction, and at the same time, when the heat exchange tube 24 is a flat tube, When the heater is used as an evaporator in an air-cooled refrigerator, the gas flow direction of the cooling air is parallel to the axial direction of the third header 13 , that is, the gas flow direction of the cooling air is parallel to the large surfaces of the heat exchange tubes 24 . When the refrigerant undergoes phase-change heat in the heat exchange tube 24, condensed water forms on the outer wall of the heat exchange tube 24, and when the temperature inside the heat exchanger is low, the tube wall of the heat exchange tube 24 freezes or frosts.

In order to remove the icing or frosting on the tube wall of the heat exchange tube 24, the heat exchange tube 24 can usually be heated by a defrosting system to melt the ice or frost on the tube wall, and the melted water will fall and be discharged under the action of gravity for heat exchange device surface. In this embodiment, when the large surface of the heat exchange tube 24 is in the vertical direction, the water content remaining on the outer wall of the heat exchange tube 24 can be reduced, thereby improving the defrosting effect.

In addition, as shown in FIG. 1, the heat exchanger may also include a plurality of fins 3, and each fin 3 is connected to adjacent heat exchange tubes 24 of each heat exchange tube row. Specifically, the fins 3 may be welded to Adjacent heat exchange tubes 24 of the same heat exchange tube row, and the fins 3 can be corrugated fins 3 without windows, and are designed according to the distance between adjacent heat exchange tubes 24 of the same heat exchange tube row, And welded with adjacent heat exchange tubes 24. Alternatively, the fins 3 can also be plate fins, which are processed in cooperation with the heat exchange tubes 24 and sleeved on the heat exchange tubes 24 . Of course, the fins 3 can also be of other structures.

In this embodiment, the fin 3 is connected to the heat exchange tube 24, the heat of the refrigerant in the heat exchange tube 24 is transferred to the tube wall of the heat exchange tube 24, and the heat of the tube wall of the heat exchange tube 24 can be conducted to the fin 3, When the air (fluid) flows through the heat exchanger, the air (fluid) can not only exchange heat with the tube wall of the heat exchange tube 24, but also exchange heat with the fins 3, thereby further increasing the heat exchange area and increasing the size of the heat exchanger. heat exchange.

In this embodiment, when the heat exchanger is used as an evaporator, along the direction L from the refrigerant inlet 112 to the refrigerant outlet 122, the density of the fins 3 decreases, that is, the density of the fins 3 near the refrigerant inlet 112 is higher than that of the fins 3 near the refrigerant inlet 112. The density of the fins 3 at the outlet 122 increases the heat exchange area of the refrigerant, which can meet the heat exchange demand at this position. At the same time, when removing the icing or frosting on the outer wall of the heat exchange tube 24, the water after the ice or frost melts falls under the action of gravity, and during the falling process, the fins 3 generate resistance to the water. When the density of the L fins 3 decreases in the direction from the refrigerant inlet 112 to the refrigerant outlet 122, the resistance during the water falling can be gradually reduced, so that the water formed after defrosting can be discharged smoothly, and the defrosting efficiency can be improved. -

Specifically, as shown in FIG. 7 , the inner cavity of the heat exchange tube 24 includes a plurality of microchannels 241, and the cross-sectional area of each microchannel 241 is relatively small, for example, the hydraulic diameter of each microchannel 241 is less than or equal to 3mm, wherein, Each microchannel 241 can be formed by arranging a plurality of baffles in the inner cavity of the heat exchange tube 24 , wherein the baffles can be integrally formed with the heat exchange tube 24 .

In addition, as shown in FIG. 7 , the end of the heat exchange tube 24 is provided with a connecting portion 241 for connecting with a corresponding header.

The above descriptions are only preferred embodiments of the present application, and are not intended to limit the present application. For those skilled in the art, there may be various modifications and changes in the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of this application shall be included within the protection scope of this application.

Claims (13)

1. A heat exchanger, the heat exchanger comprising:

the collecting pipe comprises at least a first collecting pipe and a second collecting pipe, wherein the first collecting pipe is provided with a refrigerant inlet, and the second collecting pipe is provided with a refrigerant outlet;

the heat exchange tube row at least comprises a first heat exchange tube row and a second heat exchange tube row;

the first heat exchange tube row comprises a plurality of heat exchange tubes communicated with the first collecting tube along the axial direction of the first collecting tube, so that the heat exchange tubes of the first heat exchange tube row are connected in parallel, and the second heat exchange tube row comprises a plurality of heat exchange tubes communicated with the second collecting tube along the axial direction of the second collecting tube, so that the heat exchange tubes of the second heat exchange tube row are connected in parallel;

the cross-sectional area of the heat exchange tubes of each heat exchange tube row is reduced or increased along the direction from the refrigerant inlet to the refrigerant outlet.

2. The heat exchanger according to claim 1, wherein when the heat exchanger is a condenser, a cross-sectional area of the heat exchange tube of each heat exchange tube row is gradually reduced in a direction from the refrigerant inlet to the refrigerant outlet;

when the heat exchanger is an evaporator, the sectional area of the heat exchange tube of each heat exchange tube row is gradually increased along the direction from the refrigerant inlet to the refrigerant outlet.

3. The heat exchanger according to claim 1, wherein the first header is provided with a plurality of first openings for connection with the heat exchange tubes of the first heat exchange tube row in an axial direction of the first header;

the second collecting pipe is provided with a plurality of second openings along the axial direction of the second collecting pipe, and the second openings are used for being connected with the heat exchange pipes of the second heat exchange pipe row;

the first openings have the same size, and the second openings have the same size;

when the heat exchanger is a condenser, the size of the first opening is larger than that of the second opening, and when the heat exchanger is an evaporator, the size of the first opening is smaller than that of the second opening.

4. A heat exchanger according to claim 3, wherein the heat exchange tube is a flat tube, and the first and second openings are oblong holes;

the length direction of the first opening is perpendicular to the axial direction of the first collecting pipe;

the length direction of the second opening is perpendicular to the axial direction of the second collecting pipe.

5. The heat exchanger of claim 2, wherein the header further comprises a plurality of third headers connecting the heat exchange tubes of adjacent heat exchange tube rows to enable refrigerant flow between adjacent heat exchange tube rows.

6. The heat exchanger of claim 5, wherein each of the heat exchange tubes of the heat exchange tube row is connected to a different one of the third headers.

7. The heat exchanger according to claim 5, wherein both ends of the third header in the axial direction are blocked, and the third header is provided with two third openings, and the two third openings are arranged in the axial direction of the third header.

8. The heat exchanger according to claim 5, wherein both ends of the third header pipe in the axial direction are blocked, and the third header pipe is provided with two or more third openings, and each of the third openings is arranged in the axial direction of the third header pipe;

the third collecting pipe further comprises a partition plate, the partition plate divides the third collecting pipe into two or more circulating spaces, and two third openings are formed in the circulating spaces.

9. The heat exchanger according to claim 7 or 8, wherein when the heat exchanger is a condenser, the third opening gradually decreases in size in a direction from the refrigerant inlet to the refrigerant outlet;

when the heat exchanger is an evaporator, the size of the third opening gradually increases along the direction from the refrigerant inlet to the refrigerant outlet.

10. The heat exchanger according to any one of claims 5 to 8, wherein a length direction of the third opening is parallel to an axial direction of the third header.

11. The heat exchanger according to any one of claims 5 to 8, wherein when the heat exchanger is an evaporator, the inner diameter of the first header is smaller than the inner diameter of the second header;

when the heat exchanger is a condenser, the inner diameter of the first collecting pipe is larger than the inner diameter of the second collecting pipe;

the inner diameters of the third collecting pipes are equal.

12. The heat exchanger according to any one of claims 1 to 8, further comprising fins connected to adjacent ones of the heat exchange tubes of each of the heat exchange tube rows;

when the heat exchanger is an evaporator, the density of the fins is reduced in a direction from the refrigerant inlet to the refrigerant outlet.

13. A refrigeration system, the refrigeration system comprising:

a compressor;

a heat exchanger in communication with the compressor;

wherein the heat exchanger is a heat exchanger according to any one of claims 1 to 12.

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