CN107702382B

CN107702382B - Microchannel evaporator

Info

Publication number: CN107702382B
Application number: CN201710374509.6A
Authority: CN
Inventors: 占丽媛; 崔凯
Original assignee: Sanhua Hangzhou Micro Channel Heat Exchanger Co Ltd
Current assignee: Sanhua Hangzhou Micro Channel Heat Exchanger Co Ltd
Priority date: 2017-05-24
Filing date: 2017-05-24
Publication date: 2020-07-07
Anticipated expiration: 2037-05-24
Also published as: CN107702382A; WO2018214912A1

Abstract

The invention provides a microchannel evaporator which comprises a first header assembly, a second header assembly and a flat pipe positioned between the first header assembly and the second header assembly, wherein the flat pipe is communicated with the first header assembly and the second header assembly, the first header assembly and the second header assembly respectively comprise at least two headers arranged side by side and a connector for connecting two adjacent headers in the thickness direction of the microchannel evaporator, at least two rows of flat pipes are arranged, openings are formed in the headers of the first header assembly, and circulation holes are correspondingly formed in the connector, so that a refrigerant can flow between the at least two headers of the first header assembly through the openings and the circulation holes. The design can still have a larger heat exchange area under the condition of smaller thickness and volume, thereby meeting the requirement of heat exchange capacity; compared with the traditional copper tube finned evaporator, the evaporator can save a large amount of space and improve the effective volume.

Description

Microchannel evaporator

Technical Field

The invention relates to the technical field of heat exchange, in particular to a microchannel evaporator applied to a refrigerator freezer.

Background

At present, in the technical field of refrigeration, a copper tube fin type (tube sheet type) heat exchanger is simple in processing technology and low in cost, and occupies a leading position. The tube sheet type fin is generally composed of round tubes and various types of fins, the round tubes are connected with the fins through expansion tubes, thermal contact resistance is large, heat exchange coefficient is low, relative motion is easy to generate between the round tubes and the fins, holes in the fins are gradually enlarged, heat exchange efficiency can be reduced, and service life is shortened. The micro-channel heat exchanger becomes a hot spot of current research as a novel efficient compact heat exchanger, and has been widely applied to automobile air conditioners and large commercial central air conditioners.

With the wider application of the micro-channel heat exchanger, in the field of household appliances, the application of the micro-channel condenser to the refrigerator is an obvious trend, and various large refrigerator enterprises begin to use the micro-channel condenser in batches.

On the refrigerator freezer, the evaporator widely used at present is a copper tube fin evaporator or an aluminum tube fin evaporator, and when the evaporator is used, a large air duct needs to be arranged in the refrigerator freezer, and the evaporator is matched with an axial flow fan to be used, so that a large volume in a box body needs to be occupied.

In view of the above, it is necessary to design a microchannel evaporator to solve the above problems.

Disclosure of Invention

The invention aims to provide a microchannel evaporator which has strong heat exchange capacity and can save installation space.

In order to achieve the above purpose, the invention provides a microchannel evaporator, which includes a first header assembly, a second header assembly, and a flat tube located between the first header assembly and the second header assembly, where the flat tube communicates the first header assembly and the second header assembly, and in the thickness direction of the microchannel evaporator, the first header assembly and the second header assembly each include at least two headers arranged side by side and a connector connecting two adjacent headers, the flat tube is also provided with at least two rows, and one end of each of the at least two rows of flat tubes is correspondingly communicated with at least two headers in the first header assembly, and the other end of each of the at least two rows of flat tubes is correspondingly communicated with at least two headers in the second header assembly, the headers of the first header assembly are provided with openings, and the connector of the first header assembly is correspondingly provided with flow holes, so that refrigerant can flow between at least two headers of the first header assembly through the openings and the flow holes.

As a further improvement of the present invention, the openings of at least two headers of the first header assembly at least partially correspond to each other, so that the refrigerant can flow in parallel and/or in series in at least two rows of flat tubes.

As a further improvement of the present invention, the microchannel evaporator further includes an inlet pipe and an outlet pipe connected to the first header assembly, the inlet pipe is communicated with one of the headers of the first header assembly, the outlet pipe is communicated with the other header of the first header assembly, and the inlet pipe and the outlet pipe are arranged in a vertically staggered manner in the height direction of the microchannel evaporator.

As a further improvement of the present invention, the header pipe has an inner cavity therein, the header pipe of the first header assembly is provided with a partition plate, the partition plate divides the inner cavity into at least two sub-chambers, and in the height direction of the microchannel evaporator, the inlet pipe is communicated with one of the two sub-chambers located at the lowermost end and the uppermost end, and the outlet pipe is communicated with the other of the two sub-chambers located at the lowermost end and the uppermost end.

As a further improvement of the invention, the flow holes are arranged on the connecting body in a straight line shape, and the collecting pipe and the connecting body are welded and fixed.

As a further improvement of the invention, the connector is composed of at least two aluminum pipes, openings at two ends of the aluminum pipes are the circulation holes, and the collecting pipe is welded and fixed with the at least two aluminum pipes.

As a further improvement of the invention, the microchannel evaporator further comprises fins connected with the flat tubes and side plates positioned on two sides of the flat tubes, in the height direction of the microchannel evaporator, the fins are positioned between two adjacent flat tubes, and the side plates are positioned on the upper and lower sides of the flat tubes.

As a further improvement of the invention, the fins are non-windowed fins and the density of the fins is FPI2 to FPI 8.

As a further improvement of the invention, the leeward side of the fin of the microchannel evaporator is flush with the same side edge of the flat tube, and the windward side of the fin extends outwards along the thickness direction of the microchannel evaporator and extends to enable the width of the fin to be larger than that of the flat tube.

As a further improvement of the invention, the leeward side of the side plate is flush with the same side edge of the flat tube, and the windward side of the side plate also extends outwards along the thickness direction of the microchannel evaporator so as to be flush with the fin on the windward side.

The invention has the beneficial effects that: in the microchannel evaporator, the first header assembly and the second header assembly are arranged to be composed of at least two headers arranged side by side and a connector for connecting two adjacent headers, and the header of the first header assembly is provided with an opening and the connector is provided with a circulation hole, so that a refrigerant can flow between the at least two headers of the first header assembly through the opening and the circulation hole and then flow between at least two rows of flat tubes; the design can still have a great heat transfer area under the condition that thickness, volume are less, reach the heat transfer ability requirement, for traditional copper pipe fin formula evaporimeter, can save a large amount of spaces.

Drawings

FIG. 1 is a schematic perspective view of a microchannel evaporator of the present invention.

FIG. 2 is an enlarged fragmentary view of FIG. 1 at the location of the first manifold assembly.

FIG. 3 is a perspective view of a first embodiment of the connector of FIG. 2.

Fig. 4 is a schematic view of a second embodiment of the fixed connection of the connecting body to the header in fig. 2.

FIG. 5 is a schematic diagram of the operation of the microchannel evaporator of the present invention.

Reference numerals

100 micro-channel evaporator; 10 a first header assembly; 11 collecting pipes; 111 a first header; 112 a second header; 113 a third header; 114 a fourth header; 12. 12' a linker; 121 flow holes; 122 contact surface; 13 a partition plate; 20 a second header assembly; 30 flat pipes; 31 a fin; 32 side plates; 40 an inlet pipe; 50 outlet pipe.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in detail with reference to the accompanying drawings and specific embodiments.

Referring to fig. 1 and 2, the present invention discloses a microchannel evaporator 100, which is mainly applied to a refrigerator, but not limited thereto.

The microchannel evaporator 100 includes a first header assembly 10, a second header assembly 20, and a flat tube 30 located between the first header assembly 10 and the second header assembly 20, wherein the flat tube 30 communicates the first header assembly 10 and the second header assembly 20, so as to realize the circulation of refrigerant among the first header assembly 10, the flat tube 30, and the second header assembly 20.

In the thickness direction of the microchannel evaporator 100, each of the first header assembly 10 and the second header assembly 20 includes at least two headers 11 arranged side by side and a connecting body 12 connecting two adjacent headers 11. The flat tubes 30 are also provided with at least two rows to be respectively and correspondingly communicated with at least two collecting tubes 11 in the first collecting tube assembly 10 and at least two collecting tubes 11 in the second collecting tube assembly 20, that is, one end of each of the at least two rows of flat tubes 30 is communicated with at least two collecting tubes 11 of the first collecting tube assembly 10, and the other end is communicated with at least two collecting tubes 11 of the second collecting tube assembly 20. The present specification will specifically describe two collecting main 11 and two rows of flat tubes 30 as an example.

The two headers of the first header assembly 10 are respectively defined as a first header 111 and a second header 112, and the two headers of the second header assembly 20 are respectively defined as a third header 113 and a fourth header 114.

The first collecting pipe 111 and the second collecting pipe 112 both have inner cavities (not shown) so as to form passages (not shown) for refrigerant to flow through respectively inside the first collecting pipe 111 and the second collecting pipe 112, the first collecting pipe 111 and the second collecting pipe 112 are both provided with partition plates 13, and the partition plates 13 divide the inner cavities of the first collecting pipe 111 and the second collecting pipe 112 into at least two sub-cavities, i.e., the passages for refrigerant to flow through are divided into at least two sections. Only one partition 13 is shown in fig. 2 for illustration; of course, in other embodiments, the number of the partition boards 13 can be designed according to actual needs, and is not limited herein.

The first collecting pipe 111 and the second collecting pipe 112 are respectively provided with a plurality of openings (not shown), and the connecting body 12 is correspondingly provided with a plurality of flow holes 121 (as shown in fig. 3), so that the refrigerant can flow into the other row of flat pipes 30 along the flat pipes 30, the first collecting pipe 111, the connecting body 12 and the second collecting pipe 112 through the mutual communication between the openings and the flow holes 121.

The openings of the first header 111 and the second header 112 are at least partially arranged to correspond to each other, and are arranged such that the refrigerant can flow in parallel and/or in series in the two rows of flat tubes 30. Specifically, when the opening of the first header 111 corresponds to the opening of the second header 112, the refrigerant in the first header 111 at the opening can flow in parallel in the two rows of flat tubes 30, that is: one part of the refrigerant directly enters one row of flat tubes 30, and the other part of the refrigerant enters the second collecting pipe 112 through the circulation holes 121 and the openings on the second collecting pipe 112 and then enters the other row of flat tubes 30; when the openings of the first collecting pipe 111 do not correspond to the openings of the second collecting pipe 112, the refrigerant at the openings of the first collecting pipe 111 can only flow into the corresponding flat pipes 30, and when the openings of the first collecting pipe 111 and the second collecting pipe 112 at other positions correspond to each other, the refrigerant flows into the other flat pipes 30, so that the refrigerant flows in the flat pipes 30 in a series connection manner.

Therefore, on the basis that the opening of the first header 111 and the opening of the second header 112 are at least partially corresponding to each other, in combination with the arrangement of the partition plate 13, multiple flow paths can be formed among the first header assembly 10, the flat tubes 30, and the second header assembly 20, thereby completing heat exchange.

The third collecting pipe 113 is connected to the first collecting pipe 111 through a row of flat pipes 30, the fourth collecting pipe 114 is connected to the second collecting pipe 112 through another row of flat pipes 30, and the third collecting pipe 113 and the fourth collecting pipe 114 are not provided with the openings, so that the refrigerant flowing into the third collecting pipe 113 can only flow into the first collecting pipe 111 again along the other flat pipes 30 in the row, but cannot directly flow into the fourth collecting pipe 114.

The third header 113 and the fourth header 114 are also provided with an inner chamber (not shown) to form a passage (not shown) through which a refrigerant flows inside the third header 113 and the fourth header 114, respectively, and the partition plate 13 is not provided in the third header 113 and the fourth header 114, so that the refrigerant is not restricted when flowing inside the third header 113 and the fourth header 114.

Referring to FIG. 3, a first embodiment of the connector 12 is shown. In this embodiment, the connection body 12 is disposed in a strip shape, and the flow holes 121 are arranged on the connection body 12 in a straight shape. The first header 111 (or the third header 113), the second header 112 (or the fourth header 114) and the connecting body 12 are welded and fixed to each other. The connecting body 12 has a contact surface 122 contacting with the first collecting pipe 111 (or the third collecting pipe 113) and the second collecting pipe 112 (or the fourth collecting pipe 114), and the contact surface 122 is arranged in an inward concave arc shape to better match with the first collecting pipe 111 (or the third collecting pipe 113) and the second collecting pipe 112 (or the fourth collecting pipe 114) to realize fixed connection. Of course, the contact surface 122 may be provided in other shapes, and only needs to match the shapes of the first header 111 (or the third header 113) and the second header 112 (or the fourth header 114), which is not limited herein.

Please refer to fig. 4, which shows a second embodiment of the connector. In this embodiment, the connecting body 12 'is composed of at least two aluminum pipes, at this time, openings at two ends of the aluminum pipes are the flow holes, and the at least two aluminum pipes are welded and fixed to the first collecting pipe 111 (or the third collecting pipe 113) and the second collecting pipe 112 (or the fourth collecting pipe 114) to realize the fixed connection among the first collecting pipe 111 (or the third collecting pipe 113), the connecting body 12', and the second collecting pipe 112 (or the fourth collecting pipe 114).

Referring to fig. 1 and 2, the microchannel evaporator 100 further includes an inlet pipe 40 and an outlet pipe 50 connected to the first header assembly 10, wherein the inlet pipe 40 is communicated with the first header 111, and the outlet pipe 50 is communicated with the second header 112. Of course, the second header assembly 20 is not provided with the inlet pipe 40 and the outlet pipe 50.

The inlet pipe 40 is disposed to be shifted up and down with respect to the outlet pipe 50 in the height direction of the microchannel evaporator 100, specifically, the inlet pipe 40 is located below the outlet pipe 50; meanwhile, the number of the flat tubes 30 communicated with the inlet tube 40 is less than that of the flat tubes 30 communicated with the outlet tube 50, and the reason for this is that: the refrigerant is in a liquid state when entering the first collecting pipe 111 from the inlet pipe 40, and has a small volume and a heavy weight; in the process that the refrigerant reaches the outlet pipe 50 through the plurality of flat pipes 30, the refrigerant absorbs heat gradually and changes from a liquid state to a gas state, the volume is increased, the weight is reduced, and therefore the number of the flat pipes 30 needs to be increased gradually in the process.

Of course, the placement positions of the inlet pipe 40 and the outlet pipe 50 can also be specifically designed according to the actual installation situation: 1. the inlet tube 40 may also be positioned above the outlet tube 50; 2. the inlet tube 40 is arranged flush with the outlet tube 50; as long as the heat exchange effect is not affected.

In the height direction of the microchannel evaporator 100, the inlet pipe 40 and the outlet pipe 50 are respectively communicated with the two sub-chambers located at the bottommost end and the topmost end, that is, the inlet pipe 40 is communicated with one of the two sub-chambers located at the bottommost end and the topmost end, and the outlet pipe 50 is communicated with the other of the two sub-chambers located at the bottommost end and the topmost end.

Microchannel evaporator 100 still include with fin 31 that flat pipe 30 links to each other and set up and be located the sideboard 32 of flat pipe 30 both sides, and in microchannel evaporator 100's direction of height, fin 31 is located between two adjacent flat pipes 30, sideboard 32 is located the upper and lower both sides of flat pipe 30. The fins 31 are non-windowed fins, and the density of the fins 31 is from FPI2 (i.e., 2 peaks per inch) to FPI8 (i.e., 8 peaks per inch). The shape of the fin 31 may be a triangle, a rectangle, or a trapezoid, and may be specifically designed according to actual requirements. It should be noted that: the side plates 32 are located on two sides of the flat pipe 30, and refer to: the side plates 32 are located on the outer sides of two flat tubes 30 located on the outermost side in the flat tubes 30, the side plates 32 are not connected with the flat tubes 30 on the outermost side, and fins 31 are arranged between the side plates 32 and the flat tubes 30 on the outermost side.

The leeward one side of fin 31 of microchannel evaporator 100 with flat pipe 30 homonymy edge looks parallel and level, windward one side are followed the outside extension of thickness direction of microchannel evaporator 100 to extend to the messenger the width of fin 31 is greater than flat pipe 30's width, so set up, effectively increased the heat transfer area of windward side on the one hand, on the other hand, fin 31 is outstanding, has increased the ice-storage and has stored up the frost volume, makes microchannel evaporator 100 difficult by ice or frost stifled die, during the defrosting drainage, and water is difficult to the adhesion, is convenient for discharge. Correspondingly, the leeward side of the sideboard 32 is also parallel and level with the same side edge of the flat pipe 30, the windward side is also along the outward extension of the thickness direction of the microchannel evaporator 100 and is parallel and level with the fin 31 on the windward side, so the installation is convenient, and the fin 31 is prevented from being deformed and damaged in the installation process.

Of course, the width of the fin 31 may also be set to be equal to the width of the flat tube 30, that is, both the leeward side and the windward side of the fin 31 are flush with the corresponding side edges of the flat tube 30, which is not limited herein.

Referring now to fig. 5, a schematic diagram (or refrigerant flow diagram) of the microchannel evaporator 100 of the present invention is shown. Firstly, after a refrigerant enters the first collecting pipe 111 through the inlet pipe 40, a part of the refrigerant directly flows to the third collecting pipe 113 through the lower half flat pipe 30 of one row of flat pipes 30 (i.e. the first flow shown in fig. 5), then flows into the upper half flat pipe 30 from the third collecting pipe 113 and returns to flow into the first collecting pipe 111 (i.e. the second flow shown in fig. 5), and then the refrigerant returning to flow into the first collecting pipe 111 enters the adjacent second collecting pipe 112 through the flow hole 121 on the connector 12 and flows towards the outlet pipe 50; the other part of the refrigerant in the first collecting pipe 111 flows into the adjacent second collecting pipe 112 through the flow hole 121 on the connector 12, then enters the lower half flat pipe 30 of the other flat pipe 30 and flows to the fourth collecting pipe 114, and then flows into the upper half flat pipe 30 from the fourth collecting pipe 114 and returns to the second collecting pipe 112 (i.e., the second flow shown in fig. 5); eventually, all of the refrigerant collects in the outlet tube 50 and exits.

As can be seen from fig. 5, the microchannel evaporator 100 of the present invention uses the connecting body 12 to firmly connect two headers 11 arranged side by side, thereby enhancing the welding stability and reliability of the headers 11. On the premise that the heat exchange performance meets the requirements, compared with an original copper tube fin type evaporator, the thickness is reduced, the space required by installation is greatly saved, meanwhile, the connecting body 12 adopts a mode of opening a plurality of circulation holes 121, a multi-flow process is formed, refrigerant distribution is more uniform, and the heat exchange effect is better. The quantity of the flat pipes 30 in each flow is different, the characteristic that the heat absorption of the refrigerant is changed from liquid to gas, and the volume is increased is conformed, the quantity of the flat pipes 30 in each flow is gradually increased, and the evaporator is more flexible than a copper pipe fin type evaporator.

Of course, when the microchannel evaporator 100 is installed, the external dimensions of the microchannel evaporator 100 can be adjusted according to the requirements of the actual installation space; the installation angle of the whole microchannel evaporator 100 (which refers to the included angle formed between the whole microchannel evaporator 100 and the horizontal plane) can also be adjusted and installed according to the actual situation; the number and the row number of the flat tubes 30 are not limited, and the flat tubes can be designed according to the requirements of actual space and heat exchange capacity.

In summary, in the microchannel evaporator 100 of the present invention, the first header assembly 10 and the second header assembly 20 are configured to be composed of at least two header pipes 11 arranged side by side and a connector 12 connecting two adjacent header pipes 11, and the header pipe 11 of the first header assembly 10 is provided with an opening and the connector 12 is provided with a flow hole 121, so that the refrigerant can flow into another row of flat pipes 30 along the flat pipes 30, the first header pipe 111, the connector 12, and the second header pipe 112 through the opening and the flow hole 121; the design can still have a great heat transfer area under the condition that thickness, volume are less, reach the heat transfer ability requirement, for traditional copper pipe fin formula evaporimeter, can save a large amount of spaces.

Although the present invention has been described in detail with reference to the preferred embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the spirit and scope of the present invention.

Claims

1. A microchannel evaporator comprising a first header assembly, a second header assembly, and flat tubes located between the first header assembly and the second header assembly, the flat tubes communicating the first header assembly with the second header assembly, wherein: in the thickness direction of the microchannel evaporator, each of the first header assembly and the second header assembly includes at least two headers arranged side by side and a connector connecting two adjacent headers, the flat tubes are also provided with at least two rows, one end of each of the at least two rows of flat tubes is correspondingly communicated with at least two headers in the first header assembly, the other end of each of the at least two rows of flat tubes is correspondingly communicated with at least two headers in the second header assembly, the headers of the first header assembly are provided with openings, the connector of the first header assembly is correspondingly provided with circulation holes, so that a refrigerant can flow between the at least two headers of the first header assembly through the openings and the circulation holes, the openings of the at least two headers of the first header assembly correspond to each other, so that the refrigerant can flow in the at least two rows of flat tubes in a parallel manner, the microchannel evaporator further comprises an inlet pipe and an outlet pipe which are connected with the first header assembly, and the number of the flat pipes communicated with the inlet pipe is less than that of the flat pipes communicated with the outlet pipe.

2. The microchannel evaporator of claim 1, wherein: the inlet pipe is communicated with one collecting pipe of the first collecting pipe assembly, the outlet pipe is communicated with the other collecting pipe of the first collecting pipe assembly, and the inlet pipe and the outlet pipe are arranged in a staggered mode in the height direction of the microchannel evaporator.

3. The microchannel evaporator of claim 2, wherein: the collecting pipe is internally provided with an inner cavity, the collecting pipe of the first collecting pipe assembly is provided with a partition plate, the partition plate divides the inner cavity into at least two sub-cavities, in addition, in the height direction of the microchannel evaporator, the inlet pipe is communicated with one of the two sub-cavities positioned at the bottommost end and the topmost end, and the outlet pipe is communicated with the other of the two sub-cavities positioned at the bottommost end and the topmost end.

4. The microchannel evaporator of claim 1, wherein: the circulation holes are arranged on the connecting body in a straight line shape, and the collecting pipe and the connecting body are welded and fixed.

5. The microchannel evaporator of claim 1, wherein: the connector is composed of at least two aluminum pipes, openings at two ends of the aluminum pipes are the circulation holes, and the collecting pipe is welded and fixed with the at least two aluminum pipes.

6. The microchannel evaporator of claim 1, wherein: the microchannel evaporator further comprises fins connected with the flat pipes and side plates positioned on two sides of the flat pipes, wherein the fins are positioned between the two adjacent flat pipes in the height direction of the microchannel evaporator, and the side plates are positioned on the upper sides and the lower sides of the flat pipes.

7. The microchannel evaporator of claim 6, wherein: the fins are non-windowed fins, and the density of the fins is FPI 2-FPI 8.

8. The microchannel evaporator of claim 6, wherein: the leeward side of the fin of the micro-channel evaporator is flush with the same side edge of the flat pipe, the windward side of the fin extends outwards along the thickness direction of the micro-channel evaporator, and the fin extends to the extent that the width of the fin is larger than that of the flat pipe.

9. The microchannel evaporator of claim 8, wherein: the leeward side of the side plate is flush with the same side edge of the flat pipe, and the windward side of the side plate also extends outwards along the thickness direction of the micro-channel evaporator so as to be flush with the fins on the windward side.