CN111947353A

CN111947353A - Divide liquid structure and microchannel heat exchanger that liquid efficiency is high

Info

Publication number: CN111947353A
Application number: CN202010900216.9A
Authority: CN
Inventors: 黄玉优; 桂涛; 吴永和
Original assignee: Gree Electric Appliances Inc of Zhuhai
Current assignee: Gree Electric Appliances Inc of Zhuhai
Priority date: 2020-08-31
Filing date: 2020-08-31
Publication date: 2020-11-17

Abstract

The invention provides a liquid separation structure with high liquid separation efficiency and a micro-channel heat exchanger. The liquid separation structure comprises a shell; a partition plate; the shell is provided with a liquid inlet and an air outlet, the liquid inlet is arranged on the separation area, and the air outlet is arranged at the top of the separation area; and the liquid distribution area is provided with a mounting hole communicated with the heat exchange tube. According to the liquid separation structure and the micro-channel heat exchanger with high liquid separation efficiency, a part of the shell is divided into the liquid separation area and the liquid separation area, the communication holes are formed in the partition plates to achieve the effect of the U-shaped communicating device, the pressure transmission is utilized to ensure that the liquid level height in the liquid separation area can reach the flat pipe at the uppermost part, so that the liquid separation area is filled with the liquid refrigerant, all the flat pipes can be ensured to be supplied with the sufficient liquid refrigerant, and the liquid separation uniformity and reliability of the pure liquid refrigerant are greatly improved because the liquid separation structure is not influenced by the flow separation of the gas refrigerant.

Description

Divide liquid structure and microchannel heat exchanger that liquid efficiency is high

Technical Field

The invention relates to the technical field of heat exchangers, in particular to a liquid separation structure with high liquid separation efficiency and a micro-channel heat exchanger.

Background

Due to the flowing complexity of the gas-liquid mixture, the liquid distribution uniformity of the gas-liquid mixture is influenced by a plurality of factors, and no method is provided for ensuring the consistent reliability of the liquid distribution uniformity in the microchannel heat exchanger. Particularly, in the micro-channel heat exchanger with the large-size flat tubes vertically arranged, the number of the flat tubes is large, uneven distribution is more serious, the performance of the micro-channel heat exchanger is greatly reduced, frosting is uneven under the low-temperature working condition, the defrosting effect is influenced, defrosting is incomplete, even the ice blocks climb due to cyclic deterioration, and finally the unit cannot operate; meanwhile, due to incomplete defrosting, the evaporation area is insufficient, the liquid refrigerant is not completely evaporated, the liquid refrigerant easily enters the compressor to form liquid impact, the operation reliability of the system is reduced, and the service life of the compressor is shortened.

Disclosure of Invention

In order to solve the technical problem that the micro-channel heat exchanger in the prior art is low in reliability due to uneven liquid separation, a liquid separation structure and a micro-channel heat exchanger which are high in liquid separation efficiency and guarantee liquid separation pressure by utilizing the principle of a U-shaped communicating vessel are provided.

A liquid separation structure, comprising:

a housing;

the partition plate is arranged in the shell and divides the shell into a liquid separation area and a separation area which are sealed relatively, a communication hole is formed in the part, close to the bottom of the shell, of the partition plate, and the liquid separation area and the separation area are communicated through the communication hole;

the shell is provided with a liquid inlet and an air outlet, the liquid inlet is arranged on the separation area, and the air outlet is arranged at the top of the separation area;

and the liquid distribution area is provided with a mounting hole communicated with the heat exchange tube.

And a filtering mechanism is arranged in the separation area and is arranged between the liquid inlet and the exhaust port.

The distance from the filtering mechanism to the air exhaust port is smaller than the distance from the filtering mechanism to the liquid inlet.

The filter mechanism's quantity is a plurality of, follows the bottom of casing to the top direction of casing, all filter mechanism sets up in series.

The sectional area of the housing gradually increases in a direction from the bottom of the housing to the top of the housing.

The section of the shell is trapezoidal, and the size of the lower bottom of the trapezoid is smaller than that of the upper bottom of the trapezoid; or the shell comprises a lower shell and an upper shell which are communicated with each other, the lower shell and the upper shell are cuboids, and the sectional dimension of the lower shell is smaller than that of the upper shell.

The areas of all the cross sections of the liquid distribution areas are equal along the direction from the bottom of the shell to the top of the shell.

The exhaust port is arranged on the top surface of the shell; or the exhaust port is arranged on the side surface of the top of the shell.

The communicating hole is arranged on the lower edge of the partition board.

The flow area of the communicating hole is larger than that of the liquid inlet.

The inlet port department is provided with the horn structure, the opening orientation of horn structure is directional the gas vent.

A microchannel heat exchanger comprises the liquid separation structure.

The microchannel heat exchanger further comprises:

the flat tubes are arranged in parallel along the vertical direction;

the gas collecting pipe is communicated with the first end of the heat exchange pipe;

the second ends of all the flat pipes are communicated with the liquid separating structure through the corresponding mounting holes;

the exhaust port is communicated with the gas collecting pipe.

And an air bypass pipe is arranged at the air outlet, and the end part of the air bypass pipe, which is far away from the air outlet, extends into the air collecting pipe.

The gas bypass pipe is provided with a one-way valve, and the flow direction of the one-way valve is directed to the gas collecting pipe from the gas outlet.

The lower part of the gas collecting pipe is provided with a gas outlet, and the end part of the gas bypass pipe extending into the gas collecting pipe is positioned near the gas outlet.

And the gas bypass pipe is provided with an adjusting mechanism.

The liquid separating structure and the micro-channel heat exchanger with high liquid separating efficiency, which are provided by the invention, divide part of the shell into the liquid separating area and the separating area, the clapboard is provided with a communication hole to realize the function of a U-shaped communicating vessel, the pressure difference is utilized to ensure that the liquid level in the liquid separation area can reach the flat tube at the uppermost part, thereby filling the liquid-state refrigerant in the liquid-separating area, ensuring that all the flat tubes can be supplied with sufficient liquid-state refrigerant, and the filtering mechanism and the exhaust port are arranged to separate the gaseous refrigerant and the liquid refrigerant in the separation zone, and the pressure fluctuation on the gas-liquid two-phase interface can be quickly transferred to the liquid-phase refrigerant on the other side of the U-shaped tube through the liquid-layer refrigerant, and the pressure increase and decrease at each height of the liquid phase are carried out synchronously, so that the influence on the flow distribution uniformity is not great, because the device is not influenced by the diversion of the gas refrigerant, the liquid-dividing uniformity and reliability of the pure liquid refrigerant are greatly improved.

Drawings

FIG. 1 is a schematic structural diagram of a microchannel heat exchanger according to an embodiment of the microchannel heat exchanger and a liquid separation structure with high liquid separation efficiency provided by the invention;

FIG. 2 is another schematic structural diagram of a microchannel heat exchanger according to an embodiment of the microchannel heat exchanger and a liquid separation structure with high liquid separation efficiency provided by the invention;

FIG. 3 is another schematic structural diagram of a microchannel heat exchanger according to an embodiment of the microchannel heat exchanger and a liquid separation structure with high liquid separation efficiency provided by the invention;

FIG. 4 is another schematic structural diagram of a microchannel heat exchanger according to an embodiment of the microchannel heat exchanger and a liquid separation structure with high liquid separation efficiency provided by the invention

In the figure:

1. a housing; 2. a partition plate; 11. a liquid separation zone; 12. a separation zone; 21. a communicating hole; 13. a liquid inlet; 14. an exhaust port; 3. a filtering mechanism; 4. flat tubes; 5. a gas collecting pipe; 6. a one-way valve; 7. an air outlet; 8. an air bypass 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 further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The liquid separating structure shown in fig. 1 to 4 includes: a housing 1; a partition plate 2 disposed inside the housing 1 and dividing the housing 1 into a relatively sealed liquid separating region 11 and a separating region 12, the partition board 2 is provided with a communicating hole 21 on the part near the bottom of the shell 1, the liquid separating area 11 and the separating area 12 are communicated through the communicating hole 21, the communicating hole 21 is utilized to enable the liquid separating area 11 and the separating area 12 to form a U-shaped communicating vessel structure, the pressure transmission effect of the U-shaped communicating vessel is utilized to ensure that the liquid filling area 11 is filled with liquid refrigerant, while the pressure fluctuation at the two-phase interface of the gaseous refrigerant and the liquid refrigerant in the separation zone 12 can be rapidly transferred to the liquid-phase refrigerant on the other side of the U-tube through the liquid-layer refrigerant, and the pressure increase and decrease at each height of the liquid phase are carried out synchronously, so that the influence on the flow distribution uniformity is not great, thereby ensuring the purity of the liquid refrigerant in the liquid separating area 11 and the uniformity and reliability of the liquid separating area 11; the shell 1 is provided with a liquid inlet 13 and an exhaust port 14, the liquid inlet 13 is arranged on the separation area 12, the exhaust port 14 is arranged at the top of the separation area 12, the refrigerant enters the separation area 12 from the liquid inlet 13 and is separated from the gaseous refrigerant in the separation area 12, so that the purity of the liquid refrigerant entering the liquid separation area 11 through the communication hole 21 is increased, and the separated gaseous refrigerant can be guided to other structures by the exhaust port 14 to reduce the pressure fluctuation in the separation area 12; the liquid separation area 11 is provided with mounting holes used for being communicated with the heat exchange tubes, the heat exchange flat tubes are fixed through the mounting holes, liquid refrigerants can enter all the heat exchange flat tubes through the mounting holes to exchange heat, the liquid separation area 11 is fully filled with the liquid refrigerants under the pressure transmission effect of the U-shaped communicating device, the influence of pressure fluctuation in the separation area 12 on the liquid separation area 11 is reduced, and liquid separation uniformity and reliability of the liquid separation structure are greatly improved.

The separation area 12 is internally provided with a filtering mechanism 3, the filtering mechanism 3 is arranged between the liquid inlet 13 and the exhaust port 14, and the refrigerant which is about to enter the exhaust port 14 is filtered by the filtering mechanism 3, so that the liquid refrigerant carried by the gaseous refrigerant is filtered and intercepted, and the liquid refrigerant is returned to the liquid refrigerant at the lower part of the separation area 12.

The distance from the filtering mechanism 3 to the exhaust port 14 is smaller than the distance from the filtering mechanism 3 to the liquid inlet 13, so that the refrigerant is ensured to be filtered after being fully separated, and the filtering effect of the filtering mechanism 3 is improved.

The number of the filter mechanisms 3 is multiple, and all the filter mechanisms 3 are arranged in series along the direction from the bottom of the shell 1 to the top of the shell 1, so that multi-layer filtering is realized, and the amount of liquid refrigerant contained in the gaseous refrigerant discharged from the gas outlet 14 is reduced as much as possible.

Along the bottom of casing 1 to the top direction of casing 1, the cross sectional area of casing 1 increases gradually, utilizes the gradual increase of cross sectional area for the space in separation zone 12 increases gradually, and the refrigerant can expand the speed reduction after getting into by inlet 13, and is more favorable to the separation of gaseous refrigerant and liquid refrigerant in the refrigerant.

The section of the shell 1 is trapezoidal, the size of the lower bottom of the trapezoid is smaller than that of the upper bottom of the trapezoid, and the purpose of gradual change is achieved by utilizing the oblique side of the trapezoid; or casing 1 includes lower casing 1 and last casing 1 that communicates each other, lower casing 1 with go up casing 1 and be the cuboid, just the cross sectional dimension of casing 1 is less than down the cross sectional dimension of last casing 1, also promptly a side of casing 1 with the shape of baffle 2 is the step to realize the purpose that cross sectional area changes.

The areas of all the cross sections of the liquid distribution area 11 are equal along the direction from the bottom of the shell 1 to the top of the shell 1.

The exhaust port 14 is arranged on the top surface of the housing 1; or the exhaust port 14 is disposed on the side of the top of the housing 1, that is, the gaseous refrigerant can be exhausted from the top of the housing 1, or can be exhausted from the side of the housing 1, specifically according to the actual requirement.

The communication hole 21 is arranged on the lower edge of the partition board 2, namely the communication hole 21 is positioned at the connecting position of the partition board 2 and the inner surface of the shell 1, thereby effectively ensuring the structure of the U-shaped communicator.

The flow area of the communication hole 21 is larger than that of the liquid inlet 13, so that excessive pressure loss of the refrigerant when the refrigerant passes through the communication hole 21 is avoided.

The liquid inlet 13 is provided with a horn structure, the opening of the horn structure faces the exhaust port 14, the separating effect of the gas-liquid two-phase refrigerant is improved by the horn structure, the gas-liquid two-phase refrigerant is expanded and reduced in speed to realize gas-liquid separation, the gas continuously rises and passes through the filtering mechanism 3, and most of the liquid-phase refrigerant falls to the liquid layer at the bottom under the action of gravity. A gap is reserved between the outer wall of the bell mouth and the inner wall of the separation area 12 and is used for the circulation of the refrigerant.

A microchannel heat exchanger comprises the liquid separation structure.

The microchannel heat exchanger further comprises: the flat tubes 4 are arranged in parallel along the vertical direction; the gas collecting pipe 5 is communicated with the first end of the heat exchange pipe; the second ends of all the flat tubes 4 are communicated with the liquid separating structure through the corresponding mounting holes; the exhaust port 14 is communicated with the gas collecting pipe 5, the refrigerant enters the separation area 12 through the liquid inlet 13 and then is separated, the liquid refrigerant enters the liquid separation area 11 through the communicating hole 21 and enters all the flat pipes 4 through the mounting holes to exchange heat, and flows into the gas collecting pipe 5 after the heat exchange in the flat pipes 4 to complete circulation, because the channel resistance of the flat pipes 4 is very large, the up-and-down flow resistance of the liquid separation area 11 is very small, therefore, the liquid separation area 11 can be filled with the liquid refrigerant, the flat pipes 4 with large resistance can be uniformly distributed, and the liquid level height in the liquid separation area 11 can be controlled by adjusting the size of the exhaust port 14.

Wherein, the flat tube 4 is provided with fins to increase the heat dissipation effect.

An air bypass pipe 8 is arranged at the air outlet 14, and the end part of the air bypass pipe 8 far away from the air outlet 14 extends into the air collecting pipe 5.

The gas bypass pipe 8 is provided with a one-way valve 6, and the flow direction of the one-way valve 6 is directed to the gas collecting pipe 5 from the gas outlet 14, so that the gaseous refrigerant in the gas collecting pipe 5 is prevented from flowing back to the liquid separating structure through the gas outlet 14.

Preferably, the axis of the gas collecting pipe 5 is parallel to the axis of the liquid separating structure, and under the condition that the section of the liquid separating structure is changed, the length of the flat pipe 4 at the lower part is slightly larger than that of the flat pipe 4 at the upper part, and the flowing resistance of the refrigerant is in positive correlation with the length, so that the uneven influence caused by gravity liquid separation is partially offset.

The lower part of the gas collecting pipe 5 is provided with a gas outlet 7, and the gas bypass pipe 8 extends into the end part of the gas collecting pipe 5 and is positioned near the gas outlet 7.

The air bypass pipe 8 is provided with an adjusting mechanism which can adjust the flow resistance in the air bypass pipe 8 or can adjust the pressure in the air bypass pipe 8, and preferably, the adjusting mechanism is an electronic expansion valve.

When the microchannel heat exchanger is used as a condenser:

high-temperature and high-pressure gas refrigerants enter from the gas outlet 7 of the gas collecting pipe 5, are uniformly distributed and enter the flat pipe 4 from the first end to be condensed with outside air to release heat, are condensed into liquid refrigerants through phase change, flow out from the second end and enter the liquid separating area 11 of the liquid separating pipe, the normal-temperature and high-pressure refrigerants flow into the liquid separating area 12 through the lower through hole of the liquid separating pipe, and the liquid level rises to the horn structure and then flows out from the liquid inlet 13. Because reverse pressure difference exists at two ends of the check valve 6 at the moment, the gas bypass pipe where the check valve 6 is located is in a stop state, no refrigerant flows, and therefore the condensation process is completed.

When the microchannel heat exchanger is used as an evaporator:

the throttled low-temperature low-pressure gas-liquid two-phase refrigerant enters from the liquid inlet 13 and then is subjected to deceleration expansion after the trumpet structure, gas-liquid separation is realized in the separation area 12, residual refrigerant liquid drops carried by the gas refrigerant are intercepted by the filtering mechanism 3 and return to a liquid layer at the lower part, the gas refrigerant enters the gas collecting pipe 5 from the gas bypass pipe through the one-way valve 6, the liquid refrigerant enters the liquid separation area 11 through the communication hole 21 and is uniformly distributed to all the flat pipes 4 for heat exchange, phase change is carried out to form a gaseous refrigerant, the gaseous refrigerant is mixed with the gaseous refrigerant discharged from the gas outlet 14 in the gas collecting pipe 5 and then is discharged out of the gas collecting.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the present invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. A liquid separation structure which is characterized in that: the method comprises the following steps:

a housing (1);

the separation plate (2) is arranged in the shell (1) and divides the shell (1) into a liquid separation area (11) and a separation area (12) which are sealed relatively, a communication hole (21) is formed in the part, close to the bottom of the shell (1), of the separation plate (2), and the liquid separation area (11) and the separation area (12) are communicated through the communication hole (21);

a liquid inlet (13) and an exhaust port (14) are arranged on the shell (1), the liquid inlet (13) is arranged on the separation area (12), and the exhaust port (14) is arranged at the top of the separation area (12);

and the liquid distribution area (11) is provided with mounting holes communicated with the heat exchange tube.

2. A liquid-separating structure according to claim 1, wherein: and a filtering mechanism (3) is arranged in the separation area (12), and the filtering mechanism (3) is arranged between the liquid inlet (13) and the air outlet (14).

3. A liquid-separating structure according to claim 2, wherein: the distance from the filtering mechanism (3) to the exhaust port (14) is smaller than the distance from the filtering mechanism (3) to the liquid inlet (13).

4. A liquid-separating structure according to claim 2, wherein: the number of the filtering mechanisms (3) is multiple, and all the filtering mechanisms (3) are arranged in series along the direction from the bottom of the shell (1) to the top of the shell (1).

5. A liquid-separating structure according to claim 1, wherein: the sectional area of the shell (1) is gradually increased along the direction from the bottom of the shell (1) to the top of the shell (1).

6. A liquid-separating structure according to claim 1, wherein: the section of the shell (1) is trapezoidal, and the size of the lower bottom of the trapezoid is smaller than that of the upper bottom of the trapezoid; or the shell (1) comprises a lower shell (1) and an upper shell (1) which are communicated with each other, the lower shell (1) and the upper shell (1) are cuboids, and the sectional dimension of the lower shell (1) is smaller than that of the upper shell (1).

7. A liquid-separating structure according to claim 1, wherein: the areas of all the cross sections of the liquid distribution areas (11) are equal along the direction from the bottom of the shell (1) to the top of the shell (1).

8. A liquid-separating structure according to claim 1, wherein: the exhaust port (14) is arranged on the top surface of the shell (1); or the exhaust port (14) is arranged on the side surface of the top of the shell (1).

9. A liquid-separating structure according to claim 1, wherein: the communication hole (21) is arranged on the lower edge of the partition plate (2).

10. A liquid-separating structure according to claim 1, wherein: the flow area of the communicating hole (21) is larger than that of the liquid inlet (13).

11. A liquid-separating structure according to claim 1, wherein: the liquid inlet (13) is provided with a horn structure, and the opening of the horn structure faces the air outlet (14).

12. A microchannel heat exchanger, characterized in that: a liquid-separating structure comprising any of claims 1-11.

13. The microchannel heat exchanger of claim 12, wherein: the microchannel heat exchanger further comprises:

the flat tubes (4) are arranged in parallel along the vertical direction;

the gas collecting pipe (5) is communicated with the first end of the heat exchange pipe;

the second ends of the flat pipes (4) are communicated with the liquid separating structure through the corresponding mounting holes;

the exhaust port (14) is communicated with the gas collecting pipe (5).

14. The microchannel heat exchanger of claim 13, wherein: an air bypass pipe (8) is arranged at the air outlet (14), and the end part, far away from the air outlet (14), of the air bypass pipe (8) extends into the air collecting pipe (5).

15. The microchannel heat exchanger of claim 14, wherein: the gas bypass pipe (8) is provided with a one-way valve (6), and the flowing direction of the one-way valve (6) is directed to the gas collecting pipe (5) from the gas outlet (14).

16. The microchannel heat exchanger of claim 15, wherein: the lower part of the gas collecting pipe (5) is provided with a gas outlet (7), and the end part of the gas bypass pipe (8) extending into the gas collecting pipe (5) is positioned near the gas outlet (7).

17. The microchannel heat exchanger of claim 14, wherein: and an adjusting mechanism is arranged on the air bypass pipe (8).