WO2019205601A1

WO2019205601A1 - Heat exchanger and air conditioner

Info

Publication number: WO2019205601A1
Application number: PCT/CN2018/116445
Authority: WO
Inventors: 张振富; 朱百发; 乔光宝; 王若峰
Original assignee: 青岛海尔空调器有限总公司
Priority date: 2018-04-28
Filing date: 2018-11-20
Publication date: 2019-10-31
Also published as: CN108613436A; CN108613436B

Abstract

A heat exchanger comprises: multiple heat exchange tubes (1), wherein every two adjacent heat exchange tubes are connected by means of a connection tube (2), and the multiple heat exchange tubes are connected in series to form a connected refrigerant channel (3). The refrigerant channel (3) has a first port (31) and a second port (32) for inflow and outflow of a refrigerant. The refrigerant channel (3) has a gradually increasing cross-section area in a direction from the first port (31) to the second port (32). The heat exchanger having the above structure can adapt to phase transitions of a refrigerant between liquid and gas, thereby reducing pressure drops as a result of changes in the volume of a refrigerant exchanging heat with the surrounding environment, and increasing a heat exchange rate.

Description

Heat exchanger and air conditioner

The present application is filed on the basis of the Chinese Patent Application Serial No. 20 181 040 244 8.4, filed on Apr. 28, 2008, the entire disclosure of which is hereby incorporated by reference.

Technical field

The invention relates to the technical field of electrical appliances, in particular to a heat exchanger and an air conditioner.

Background technique

In the field of air conditioning or refrigerator technology, heat exchangers are extremely important components in order to achieve temperature adjustment. The heat exchangers are mainly of two types: parallel flow type and serpentine type. The serpentine tube heat exchanger is widely used because of its simple structure and convenient manufacturing and processing. The heat exchanger mainly realizes heat exchange by changing the gas-liquid state of the refrigerant.

At present, energy conservation is getting more and more attention. In order to improve the efficiency of heat exchange, a heat exchanger composed of two kinds of serpentine heat exchange tubes with different flow areas is disclosed in the related art to reduce the change of the state of the refrigerant in two types. The pressure drop between the serpentine heat exchange tubes. However, after the heat exchanger disclosed in the prior art is formed, the length of the serpentine heat exchange tube having different flow areas is fixed, and the refrigerant quantity is too small or too large, and the change of the refrigerant state occurs in one of the serpentine heat exchange tubes. The pressure drop at the time is poorly applicable.

Summary of the invention

Embodiments of the present invention provide a heat exchanger and an air conditioner, which have solved the problem of poor applicability of the heat exchanger in the prior art. In order to have a basic understanding of some aspects of the disclosed embodiments, a brief summary is given below. This generalization is not a general comment, nor is it intended to identify key/critical constituent elements or to describe the scope of protection of these embodiments. Its sole purpose is to present some concepts in a simplified form as a prelude to the following detailed description.

According to a first aspect of the present invention, there is provided a heat exchanger comprising: two or more heat exchange tubes, wherein each of the two adjacent heat exchange tubes passes through the one of the connections The tubes are connected, and the plurality of heat exchange tubes are connected in series to form a communicating refrigerant passage; the refrigerant passage has a first port and a second port for the refrigerant to flow in or out; the cross-sectional area of the refrigerant passage is along the first port to The direction of the second port gradually increases.

In some alternative embodiments, the heat exchange tubes are round tubes, flat tubes or elliptical tubes.

In some optional embodiments, the heat exchange tube is a circular tube; a wall of the heat exchange tube gradually increases/decreases in a direction from the first port to the second port. Optionally, the wall thickness is 0.25 mm to 0.5 mm; the outer diameter of the heat exchange tube is 6 mm to 10 mm. Preferably, the wall thickness of the tube is 0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm, 0.45 mm and 0.5 mm; the outer diameter of the heat exchange tube is 6 mm, 6.5 mm, 7 mm, 7.5 mm, 8 mm, 8.5 mm, 9 mm , 9.5mm or 10mm.

In some optional embodiments, the cross-sectional area of the refrigerant passage gradually decreases in magnitude along the direction from the first port to the second port.

Optionally, the cross-sectional area of the refrigerant passage is determined according to the following formula:

Where y is the cross-sectional area of the refrigerant passage; x is the distance from the first port; b is the cross-sectional area of the refrigerant passage at the first port; a is an adjustment factor; a is in the range of 0< a<1.

In some optional embodiments, when the heat exchange tube is a circular tube, an outer diameter of the heat exchange tube gradually increases along a direction from the first port to the second port; when the heat exchange tube is When the tube is flat, the width or height of the heat exchange tube gradually increases along the first port to the second port, or the width and height of the heat exchange tube along the first port to the first The direction of the two ports is gradually increased; when the heat exchange tube is an elliptical tube, the long or short diameter of the heat exchange tube gradually increases along the direction from the first port to the second port, or the change The long diameter and the short diameter of the heat pipe gradually increase in the direction from the first port to the second port.

In some optional embodiments, the inner wall of the heat exchange tube has a straight groove parallel to the axial direction of the heat exchange tube, a spiral groove having a prescribed twist angle with respect to the heat transfer tube axis, or A cross groove formed by a groove intersecting in the axial direction of the heat exchange tube.

In some alternative embodiments, the heat exchange tubes are copper or aluminum tubes.

In some optional embodiments, the inner and outer walls of the heat exchange tube further comprise: a thermally conductive coating; the thermal conductivity of the thermally conductive coating is greater than a thermal conductivity of the refrigerant tube.

In some optional embodiments, the method further includes: fins; each of the outer walls of the heat exchange tubes is provided with a plurality of fins that are parallel to each other.

In some alternative embodiments, the fins are disposed on an outer wall of the heat exchange tube by a welding process or a shoveling process.

In some alternative embodiments, the area of the fins gradually decreases in the direction from the first port to the second port.

In some alternative embodiments, the fins are wavy plate shaped.

According to a first aspect of an embodiment of the present invention, there is provided an air conditioner comprising any of the aforementioned heat exchangers.

The technical solutions provided by the embodiments of the present invention may include the following beneficial effects:

The heat exchanger provided by the embodiment of the invention comprises a plurality of heat exchange tubes, and the adjacent two heat exchange tubes are connected in series by the connecting tubes to form a refrigerant passage, and the cross-sectional area of the refrigerant passage is gradually increased along the direction from the first port to the second port. In order to adapt to changes in the state of the refrigerant gas and liquid, reduce the pressure drop caused by the volume increase during the heat exchange between the refrigerant and the surrounding environment, increase the heat exchange rate, and save energy.

The above general description and the following detailed description are intended to be illustrative and not restrictive.

DRAWINGS

The accompanying drawings, which are incorporated in the specification of FIG

1 is a cross-sectional view of a heat exchanger along an axial direction of a heat exchange tube, according to an exemplary embodiment;

2a is a schematic cross-sectional view showing a direction of an axial direction of a heat exchange tube of a heat exchanger according to an exemplary embodiment;

2b is a schematic cross-sectional view of a vertical direction of a heat exchange tube of a heat exchanger according to an exemplary embodiment;

2c is a schematic cross-sectional view of a heat exchanger vertical heat exchange tube in the axial direction, according to an exemplary embodiment.

detailed description

The detailed description of the embodiments of the invention are set forth in the description Portions and features of some embodiments may be included or substituted for portions and features of other embodiments. The scope of the embodiments of the invention includes the full scope of the claims, and all equivalents of the claims. Herein, relational terms such as first and second are used to distinguish one entity or structure from another entity or structure, and do not require or imply any actual relationship between the entities or structures or order. The various embodiments herein are described in a progressive manner, and each embodiment focuses on differences from other embodiments, and the same similar parts between the various embodiments may be referred to each other.

In the description of the present invention, it is to be understood that the terms "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", The orientation or positional relationship of the indications of "horizontal", "top", "bottom", "inside", "outside", etc. is based on the orientation or positional relationship shown in the drawings, only for the convenience of describing the present invention and simplifying the description, rather than It is to be understood that the device or elements referred to have a particular orientation, are constructed and operated in a particular orientation and are therefore not to be construed as limiting. In the description of the present invention, unless otherwise specified and limited, it should be noted that the terms "mounted", "connected", and "connected" are to be understood broadly, and may be, for example, mechanical or electrical, or both. The internal communication of the components may be directly connected or indirectly connected through an intermediate medium. For those skilled in the art, the specific meanings of the above terms may be understood according to specific circumstances.

As shown in FIG. 1 , the heat exchanger provided by the embodiment of the present invention includes a plurality of heat exchange tubes 1 . Each adjacent two heat exchange tubes 1 are connected by a connecting tube 2, and a plurality of heat exchange tubes 1 are connected in series to form a communicating refrigerant passage 3. In order to save space, a plurality of heat exchange tubes 1 are connected in series to form a serpentine refrigerant passage 3, and the refrigerant circulates in the refrigerant passage 3 to exchange heat with the external environment to realize heat exchange of the heat exchanger.

Wherein, the heat exchange tubes 1 are connected in such a manner that the heat exchange tubes 1 are arranged in parallel, and each adjacent two heat exchange tubes 1 are connected by a connecting tube 2. Optionally, the connecting tube 2 is a U-shaped connecting tube. The refrigerant exchanges heat with the external environment in the refrigerant passage 3, and a gas-liquid state change occurs. In order to realize the gas-liquid circulation of the refrigerant, the refrigerant passage 3 has a first port 31 and a second port 32 through which the refrigerant flows in or out, and the cross-sectional area of the refrigerant passage 3 gradually increases in the direction from the first port 31 to the second port 32. The pressure drop caused by the continuous change of the state of the refrigerant in the refrigerant passage 3 is reduced, the heat exchange efficiency is improved, and energy consumption is saved.

In the present embodiment, when the refrigerant flows in from the first port 31, the liquid is in a liquid state, and the temperature is low and the volume is small. As the refrigerant flows in the refrigerant passage 3 and exchanges heat with the outside, the refrigerant absorbs heat and vaporizes, and the volume increases. When the cross-sectional area of the refrigerant passage 3 is constant, as the refrigerant vaporizes and the volume increases, the flow resistance of the heat exchange tube 1 to the refrigerant increases. The cross-sectional area of the refrigerant passage 3 gradually increases along the direction from the first port 31 to the second port 32, which reduces the flow resistance of the heat exchange tube 1 to the refrigerant during the flow of the refrigerant, reduces the pressure drop, and improves the heat exchange efficiency. Save energy. Similarly, when the refrigerant flows from the second port 32, it is in a gaseous state, and the temperature is high and large. As the refrigerant flows in the refrigerant passage 3 and exchanges heat with the outside, the refrigerant releases heat and liquefies, and the volume is reduced. When the cross-sectional area of the refrigerant passage 3 is constant, the volume decreases as the refrigerant liquefies. The cross-sectional area of the refrigerant passage 3 gradually increases along the direction from the first port 31 to the second port 32, which reduces the flow resistance of the heat exchange tube 1 to the refrigerant when the refrigerant flows in through the second port 32, reduces the pressure drop, and improves Heat exchange efficiency and energy saving.

The heat exchanger provided by the embodiment of the invention can be used as a condenser or an evaporator. Because the cross-sectional area of the refrigerant passage 3 changes gradually along the direction from the first port 31 to the second port 32, the resistance of the heat exchange tube 1 to the refrigerant when the refrigerant flows in the refrigerant passage 3 is reduced, and the pressure is reduced. drop. Therefore, when the heat exchanger provided by the embodiment of the present invention acts as an evaporator, the refrigerant flows in from the first port 31 and flows out from the second port 32. When the heat exchanger provided by the embodiment of the present invention acts as a condenser, the refrigerant is The two ports 32 flow in and flow out from the first port 31.

In the embodiment of the present invention, the heat exchange tubes 1 are in various forms as shown in Figs. 2a, 2b and 2c. Optionally, the heat exchange tube 1 is a round tube, a flat tube or an elliptical tube.

In some alternative embodiments, the heat exchange tubes 1 are round tubes. Optionally, the wall thickness is 0.25 mm to 0.5 mm; and the outer diameter of the heat exchange tube 1 is 6 mm to 10 mm. Preferably, the wall thickness of the tube is 0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm, 0.45 mm and 0.5 mm; the outer diameter of the heat exchange tube 1 is 6 mm, 6.5 mm, 7 mm, 7.5 mm, 8 mm, 8.5 mm, 9 mm, 9.5mm or 10mm.

In some alternative embodiments, the heat exchange tubes 1 are flat tubes. Optionally, the wall thickness is 0.25 mm to 0.5 mm; the heat exchange tube 1 has a width of 6 mm to 10 mm; and the heat exchange tube 1 has a width of 6 mm to 10 mm. Preferably, the wall thickness of the tube is 0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm, 0.45 mm and 0.5 mm; the width or height of the heat exchange tube 1 is 6 mm, 6.5 mm, 7 mm, 7.5 mm, 8 mm, 8.5 mm, 9 mm. , 9.5mm or 10mm.

In some alternative embodiments, the heat exchange tubes 1 are elliptical tubes. Optionally, the wall thickness is 0.25 mm to 0.5 mm; the long diameter of the heat exchange tube 1 is 6 mm to 10 mm; and the width of the heat exchange tube 1 is 6 mm to 10 mm. Preferably, the wall thickness of the tube is 0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm, 0.45 mm and 0.5 mm; the long diameter of the heat exchange tube 1 is 6 mm, 6.5 mm, 7 mm, 7.5 mm, 8 mm, 8.5 mm, 9 mm, 9.5mm or 10mm.

In some alternative embodiments, the cross-sectional area of the refrigerant passage 3 gradually decreases in the direction of the first port 31 to the second port 32. Alternatively, the cross-sectional area of the refrigerant passage 3 is calculated as follows:

Where y is the cross-sectional area of the refrigerant passage 3; x is the distance from the first port 31; b is the cross-sectional area of the refrigerant passage 3 at the first port 31; a is an adjustment coefficient; a has a value range of 0< a<1.

When the heat exchanger is used as the evaporator, the refrigerant flows from the first port 31, the temperature of the refrigerant is lower, and the heat exchange rate is faster. The heat exchange rate is slowed down as the temperature of the vaporized refrigerant gradually increases with the surrounding environment. In some embodiments, when the refrigerant passage 3 of the heat exchanger is long, the refrigerant is completely vaporized and continuously exchanges heat with the surrounding environment, and the temperature of the second port 32 is equal to the ambient temperature, although the refrigerant passage 3 is horizontal. The increase of the cross-sectional area along the direction of the first port 31 to the second port 32 can reduce the pressure drop of the refrigerant, increase the heat exchange rate, and save energy, but as the cross-sectional area of the refrigerant passage 3 increases, the heat exchanger is increased. cost. The increase in the cross-sectional area of the refrigerant passage 3 in the direction of the first port 31 to the second port 32 is gradually reduced, which not only reduces the refrigerant pressure drop, increases the heat exchange rate, saves energy, and at the same time reduces the manufacturing cost.

When the heat exchanger functions as a condenser, the cross-sectional area of the refrigerant passage 3 gradually increases in the direction of decreasing from the first port 31 to the second port 32. The refrigerant flows from the second port 32, the temperature of the refrigerant is high, the volume is large, the area of contact with the inner wall of the heat exchange tube 1 is limited, the heat exchange is slow, and the temperature of the liquefied refrigerant gradually decreases with the surrounding environment, and the volume decreases. The reduction of the cross-sectional area of the refrigerant passage 3 is gradually increased to ensure sufficient contact between the refrigerant and the pipe wall to accelerate the heat exchange efficiency.

In some alternative embodiments, when the heat exchange tube 1 is a circular tube, the outer diameter of the heat exchange tube 1 gradually increases in the direction from the first port 31 to the second port 32. In some alternative embodiments, when the heat exchange tube 1 is a flat tube, the width or height of the heat exchange tube 1 gradually increases in the direction of the first port 31 to the second port 32, or the width and height of the heat exchange tube 1 The direction gradually increases along the first port 31 to the second port 32. In some alternative embodiments, when the heat exchange tube 1 is an elliptical tube, the long or short diameter of the heat exchange tube 1 gradually increases in the direction of the first port 31 to the second port 32, or the length of the heat exchange tube 1 The diameter and the short diameter gradually increase in the direction from the first port 31 to the second port 32.

In some alternative embodiments, in order to increase the contact area between the refrigerant and the inner wall of the heat exchange tube 1, the inner wall of the heat exchange tube 1 has a straight groove parallel to the axial direction of the heat exchange tube 1, and has a prescribed state with respect to the axis of the heat exchange tube 1. A spiral groove having a twist angle or a cross groove formed by a groove intersecting in the axial direction of the heat transfer tube 1. The inner wall of the heat exchange tube 1 has a groove, which increases the contact area between the refrigerant and the inner wall of the heat exchange tube 1, and increases the heat exchange rate.

In any of the foregoing embodiments, the tube of the heat exchange tube 1 is of a variety of options. Optionally, the heat exchange tube 1 is a copper tube or an aluminum tube.

In some alternative embodiments, to further increase the heat exchange rate, the inner and outer walls of the heat exchange tube 1 further comprise: a thermally conductive coating. The thermal conductivity of the thermally conductive coating is greater than the thermal conductivity of the heat exchange tube 1.

In any of the foregoing embodiments, in order to increase the heat exchange rate, the heat exchanger further includes: fins 4. A plurality of fins 4 parallel to each other are disposed on the outer wall of each heat exchange tube 1, and the fins 4 are disposed perpendicular to the axial direction of the heat exchange tube 1, because the contact area of the heat exchange tube 1 with the external environment is limited, and the heat exchange area is small. If the heat transfer area is increased by thickening the pipe wall, not only the cost is increased, the process difficulty is increased, and the heat exchange effect is even weakened, and the fin 4 is in contact with the outer wall of the heat exchange tube 1 and is perpendicular to the axis of the heat exchange tube 1 To the epitaxy, the heat exchange area of the heat exchanger is increased, and the heat exchange efficiency of the heat exchanger is improved. Alternatively, the fins 4 are aluminum fins 4 or copper fins 4.

In some alternative embodiments, to further increase the heat transfer rate, the surface of the fin 4 further includes a thermally conductive coating. The thermal conductivity of the thermally conductive coating is greater than the thermal conductivity of the fins 4.

There are various ways in which the fins 4 are disposed on the outer wall of the heat transfer tube 1. In some alternative embodiments, the fins 4 are disposed on the outer wall of the heat exchange tube 1 by a welding process. In some alternative embodiments, after the tube type of the heat exchange tube 1 is selected, the outer wall of the heat exchange tube 1 is subjected to a shoveling process to machine the fin 4 structure.

Preferably, in the heat exchange tube 1 of the heat exchanger of the embodiment of the invention, an aluminum tube is used, and the outer wall of the heat exchange tube 1 is processed by a shoveling process to form the fin 4 structure. Among them, in order to reduce the processing difficulty of the heat exchanger and improve the processing efficiency, the aluminum tube with less hardness is selected to avoid the solder joint damage in the form of the combination of the heat exchange tube 1 and the fin 4 by the welding process, and the fin 4 is poured to affect the heat exchange. In the efficiency, the shingling process is used to process the fins 4 on the outer wall of the heat exchange tube 1. At the same time, the heat exchanger provided by the embodiment of the invention has small weight and is convenient for handling and installation.

In some alternative embodiments, the area of the fins 4 tapers in the direction of the first port 31 to the second port 32. When the heat exchanger is used as an evaporator, the refrigerant flows from the first port 31, and the temperature of the refrigerant is low. As the temperature of the vaporized refrigerant gradually increases with the surrounding environment, the heat exchange rate is slowed down. In some embodiments, when the refrigerant passage 3 of the heat exchanger is long, the refrigerant is completely vaporized and continuously exchanges heat with the surrounding environment, and the temperature of the second port 32 is equal to the ambient temperature, and no heat exchange occurs with the outside. . In this embodiment, the area of the fins 4 gradually decreases along the direction from the first port 31 to the second port 32, which can meet the requirement of increasing the heat exchange area of the heat exchanger, improve the heat exchange rate, save energy, and can Reduce production costs.

When the heat exchanger is used as a condenser, the refrigerant flows from the second port 32, the temperature of the refrigerant is high, the volume is large, the area of contact with the inner wall of the heat exchange tube 1 is limited, the heat exchange is slow, and the heat exchange with the surrounding environment is liquefied. The temperature of the refrigerant is gradually decreased, the volume is decreased, the width of the cross-sectional area of the refrigerant passage 3 is gradually increased, the heat exchange efficiency is increased, and the area of the fin 4 is gradually decreased along the direction from the first port 31 to the second port 32, that is, The direction gradually increases along the first port 31 to the second port 32, which can meet the requirement of increasing the heat exchange area of the heat exchanger, improve the heat exchange rate, save energy consumption, and reduce the manufacturing cost.

An embodiment of the present invention further provides an air conditioner comprising the heat exchanger provided by any of the above embodiments.

The invention is not limited to the structures that have been described above and shown in the drawings, and various modifications and changes can be made without departing from the scope thereof. The scope of the invention is limited only by the appended claims.

Claims

A heat exchanger comprising: a plurality of heat exchange tubes, wherein each of the two adjacent heat exchange tubes is connected by one of the connecting tubes, and the plurality of heat exchange tubes are connected in series to form a connected refrigerant passage; The refrigerant passage has a first port and a second port through which refrigerant flows in or out; a cross-sectional area of the refrigerant passage gradually increases in a direction from the first port to the second port.
The heat exchanger according to claim 1, wherein said heat exchange tubes are round tubes, flat tubes or elliptical tubes.
A heat exchanger according to claim 2, wherein a cross-sectional area of said refrigerant passage has a cross-sectional area of a pattern enclosed by an inner wall of said heat transfer tube along said first port to said second port The magnitude of the increase in direction gradually decreases.
A heat exchanger according to claim 1, wherein said inner wall of said heat exchange tube has a straight groove parallel to the axial direction of said heat exchange tube, and has a predetermined twist angle with respect to said heat transfer tube axis A spiral groove or a cross groove formed by a groove intersecting in the axial direction of the heat transfer tube.
The heat exchanger according to claim 1, wherein said heat exchange tubes are copper tubes or aluminum tubes.
The heat exchanger according to claim 1, wherein the inner wall and the outer wall of the heat exchange tube further comprise: a heat conductive coating; the thermal conductivity of the heat conductive coating is greater than a thermal conductivity of the heat exchange tube.
A heat exchanger according to claim 1, further comprising: fins; each of said outer tubes of said heat exchange tubes is provided with a plurality of fins parallel to each other; said fins being perpendicular to said heat exchange tubes Set in the direction of the axis.
The heat exchanger according to claim 7, wherein said fins are disposed on an outer wall of said heat exchange tube by a welding process or a shovel process.
The heat exchanger according to claim 7, wherein an area of said fin gradually decreases in a direction from said first port to said second port.
An air conditioner comprising the heat exchanger according to any one of claims 1 to 9.