WO2024021698A1

WO2024021698A1 - Shell-and-tube heat exchanger and air conditioning unit

Info

Publication number: WO2024021698A1
Application number: PCT/CN2023/089539
Authority: WO
Inventors: 王宗信; 胡东兵; 胡海利; 游浩亮
Original assignee: 珠海格力电器股份有限公司
Priority date: 2022-07-27
Filing date: 2023-04-20
Publication date: 2024-02-01
Also published as: CN115183605A

Abstract

The present disclosure provides a shell-and-tube heat exchanger and an air conditioning unit. The shell-and-tube heat exchanger comprises a shell and, disposed in the shell, a flash evaporation structure and a liquid separation structure; a refrigerant inlet is formed in the shell; the liquid separation structure is arranged on a side of the flash evaporation structure away from the refrigerant inlet, and refrigerant entering the refrigerant inlet sequentially flows through the flash evaporation structure and the liquid separation structure. In the shell-and-tube heat exchanger and the air conditioning unit provided in the present disclosure, arranging the flash evaporation structure in the shell-and-tube heat exchanger increases the level of product integration, reduces the use of a connecting pipeline, and thus reduces the safety hazards of pipeline vibration and refrigerant leakage. Moreover, refrigerant throttled by the flash evaporation structure then being subjected to gas-liquid separation can improve liquid separation uniformity, and simultaneously reduces the problem of refrigerant splashing as a result of the refrigerant impacting an outer wall surface of a heat exchange pipe, enhancing the film distribution effect, and improving the heat transfer coefficient.

Description

Shell and tube heat exchangers and air conditioning units

Cross-references to related applications

This disclosure is based on the application with CN application number 202210892514.7 and the filing date is July 27, 2022, and claims its priority. The disclosure content of the CN application is hereby incorporated into this disclosure as a whole.

Technical field

The present disclosure relates to the technical field of air treatment equipment, in particular to a shell and tube heat exchanger and an air conditioning unit.

Background technique

In addition to the four main components of the compressor, condenser, throttling device, and evaporator, the refrigeration system also requires auxiliary components such as oil separators, flashers, and gas-liquid separators to improve unit performance. At the same time, it is equipped with pipelines and electronic controls. equipment to ensure reliable operation of the unit. In centrifugal chillers, two-stage compression and two-stage throttling are often used in the refrigeration cycle with incomplete cooling in the middle. That is, the high-temperature and high-pressure refrigerant coming out of the condenser enters the flasher through the first-stage throttling orifice plate to achieve gas-liquid separation. Between the air supply to the high- and low-pressure stage compressors, the liquid enters the evaporator through the secondary throttling orifice plate.

In particular, the centrifuge uses a two-stage compression and two-stage throttling refrigeration cycle with incomplete cooling in the middle. Compared with the single-stage compression refrigeration cycle, the system's capacity and energy efficiency are improved and the exhaust temperature of the compressor is reduced. However, it also increases the savings. Orifice plate, flasher and connecting pipe fittings. On the one hand, the new parts increase the manufacturing cost of the unit, and the flashlight adds safety hazards to the pressure vessel. On the other hand, it also increases the risk of vibration and refrigerant leakage in the connecting pipelines.

Contents of the invention

In order to solve the technical problems such as vibration of connecting pipes and leakage of refrigerant due to the complex structure of refrigeration systems in the prior art, a shell and tube heat exchanger that combines a flash structure with a heat exchange structure to reduce structural complexity is provided. Air conditioning units.

A first aspect of the present disclosure provides a shell-and-tube heat exchanger, including a shell and a flash structure and a liquid separation structure disposed in the shell. The shell is provided with a refrigerant inlet, and the liquid separation structure It is arranged on the side of the flash structure away from the refrigerant inlet, and the refrigerant entering from the refrigerant inlet flows through the flash structure and the liquid separation structure in sequence.

The flash structure includes at least two throttle plates, all of which are along a direction away from the refrigerant inlet. are arranged side by side in the casing, and the uppermost throttle plate and the corresponding casing and the two adjacent throttle plates and the corresponding casing all enclose a third A gas-liquid separation space, the refrigerant entering from the refrigerant inlet flows through all the first gas-liquid separation spaces in sequence.

One end of the throttle plate is provided with a throttle hole, and the throttle holes of two adjacent throttle plates are arranged in a staggered manner.

All the throttle plates include at least a second throttle plate located at the lowest level. The second throttle plate is formed with an inclined portion having an angle with the horizontal plane, and the orifice is provided on the inclined portion. .

Along the width direction of the second throttle plate, the second throttle plate includes a planar portion and an inclined portion arranged side by side, and there is a gap between the planar portion and the inclined portion and the adjacent throttle plate. There is a gap for the circulation of refrigerant, and the size of the gap between the inclined part and the adjacent throttle plate gradually increases in a direction away from the flat part.

The housing is provided with an air supply port, and the air supply port is connected with the gap.

The flash structure also includes a filtrate plate, the filtrate plate is arranged on the inclined part, the filtrate plate is provided with filtrate holes, and the filtrate plate, part of the inclined part and the corresponding shell Together they form a liquid accumulation space located below the filtrate plate, and the filtrate plate, part of the inclined portion, the adjacent throttle plate and the corresponding housing together form a space located above the filtrate plate. The first gas-liquid separation space.

The flash structure also includes a plurality of baffles, all of which are staggeredly arranged in the first gas-liquid separation space.

The liquid separation structure includes a flow plate, and all of the throttle plates include a second throttle plate located at the bottom. The flow plate is arranged below the second throttle plate, and the flow plate , a second gas-liquid separation space is enclosed between the second throttle plate and the corresponding housing.

The overflow plate is provided with an overflow hole, and the overflow hole is offset from the orifice on the second throttle plate.

The shell and tube heat exchanger includes a side baffle, which is located below the second throttle plate, on one side of the flow plate, and on the third side of the side baffle. On one side, the flow plate, the second throttle plate and part of the side baffles together form the second gas-liquid separation space. On the second side of the side baffles, the The side baffles and the corresponding housing form an exhaust area.

An air outlet is provided on the side baffle, and the second gas-liquid separation space and the exhaust area are connected through the air outlet.

A filtering mechanism is provided at the air outlet.

The overflow plate is provided with an overflow hole, and the air outlet is located above the overflow hole.

An exhaust port is provided on the housing, and an air baffle is provided between the air outlet and the exhaust port.

The shell-and-tube heat exchanger also includes a plurality of heat exchange tubes, all of the heat exchange tubes are arranged below the liquid separation structure, and all of the heat exchange tubes are located on the third side of the side baffle. one side.

The liquid separation structure also includes at least two liquid separation plates, all of the liquid separation plates are arranged side by side below the flow plate, and the adjacent liquid separation plates are between the uppermost liquid separation plate and the flow plate. A liquid separation space is formed between the two liquid separation plates.

The liquid separation plate is provided with liquid separation holes, and the liquid separation holes on two adjacent liquid separation plates are arranged staggeredly.

The flashing structure includes at least two throttling plates, and the liquid separation structure also includes at least two liquid separation plates. The throttling plate in the uppermost layer and the liquid separation plate in the lowermost layer are on the same side. Side sealing plates are connected between the edges, and the side sealing plates are arranged in conformity with the corresponding parts of the housing.

A second aspect of the present disclosure provides an air conditioning unit, including the above-mentioned shell and tube heat exchanger.

The shell-and-tube heat exchanger and air-conditioning unit provided by the present disclosure have a flash structure built into the shell-and-tube heat exchanger, which improves product integration, reduces the use of connecting pipelines, and reduces safety risks of pipeline vibration and refrigerant leakage. , at the same time, the refrigerant after being throttled by the flash structure is undergoing gas-liquid separation, so that the liquid-separating structure can separate the liquid refrigerant after gas-liquid separation, which can improve the uniformity of liquid separation and reduce the impact heat transfer of the refrigerant. Avoid the problem of refrigerant splashing outside the tube, enhance the film distribution effect, and improve the heat transfer coefficient.

Description of drawings

Figure 1 is a schematic structural diagram of a flash structure and a liquid separation structure according to an embodiment of the present disclosure;

Figure 2 is another structural schematic diagram of an embodiment provided by the present disclosure;

Figure 3 is a cross-sectional view of a shell and tube heat exchanger according to an embodiment of the present disclosure;

Figure 4 is another cross-sectional view of a shell and tube heat exchanger according to an embodiment of the present disclosure;

Figure 5 is another cross-sectional view of a shell and tube heat exchanger according to an embodiment of the present disclosure;

Figure 6 is a schematic structural diagram of a throttle plate according to an embodiment of the present disclosure;

Figure 7 is a schematic structural diagram of a second throttle plate according to an embodiment of the present disclosure;

Figure 8 is a schematic structural diagram of a filtrate plate according to an embodiment of the present disclosure;

Figure 9 is a schematic structural diagram of a flow plate according to an embodiment of the present disclosure;

Figure 10 is a schematic structural diagram of the side baffle and the flow plate according to the embodiment of the present disclosure;

Figure 11 is a schematic structural diagram of the side sealing plate, throttle plate and liquid separation plate according to the embodiment of the present disclosure;

In the picture:

1. Shell; 2. Flash structure; 3. Liquid separation structure; 101. Refrigerant inlet; 21. Throttle plate; 22. First gas-liquid separation space; 211. Throttle hole; 212. Second throttling plate; 213, inclined part; 214, flat part; 102, air supply port; 23, filtrate plate; 231, filtrate hole; 24, liquid accumulation space; 25, baffle; 31, flow plate; 26, second air Liquid separation space; 311, overflow hole; 4, side baffle; 103, exhaust area; 41, air outlet; 42, air baffle; 5, filter mechanism; 104, exhaust port; 6, heat exchange tube ; 32. Liquid separation plate; 33. Liquid separation space; 321. Liquid separation hole; 7. Side sealing plate.

Detailed ways

In order to make the purpose, technical solutions and advantages of the present disclosure more clear, the present disclosure will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present disclosure and are not intended to limit the present disclosure.

The shell and tube heat exchanger shown in Figures 1 to 11 includes a shell 1 and a flash structure 2 and a liquid separation structure 3 arranged in the shell 1. The shell 1 is provided with refrigerant. Inlet 101, the liquid separation structure 3 is disposed on the side of the flash structure 2 away from the refrigerant inlet 101, and the refrigerant entering the refrigerant inlet 101 flows through the flash structure 2 and the refrigerant inlet 101 in sequence. Describe the liquid separation structure 3. The refrigerant entering through the refrigerant inlet 101 sequentially passes through the throttling of the flashing structure 2 and the liquid separation of the liquid separation structure 3, and then comes into contact with the heat exchange tube provided in the shell 1 to complete the flashing of the refrigerant. Liquid separation and heat exchange. The flash structure 2 is built into the shell-and-tube heat exchanger to improve product integration, reduce the use of connecting pipelines, and reduce the safety risks of pipeline vibration and refrigerant leakage. At the same time, the refrigerant after the flash structure 2 is throttled is in Gas-liquid separation can improve the uniformity of liquid separation, while reducing the problem of refrigerant splashing caused by impact on the outside of the heat exchange tube, enhancing the film distribution effect and improving the heat transfer coefficient.

The flash structure 2 includes at least two throttling plates 21. All the throttling plates 21 are arranged side by side in the housing 1 in a direction away from the refrigerant inlet 101, and the uppermost throttling plate 21 is A first gas-liquid separation space 22 is formed between the plate 21 and the corresponding housing 1 and between two adjacent throttle plates 21 and the corresponding housing 1. The refrigerant inlet 101 The incoming refrigerant flows through all the first gas-liquid separation spaces 22 in sequence. By arranging multiple throttling plates 21, the refrigerant is throttled multiple times inside the shell 1, and the refrigerant in the first gas-liquid separation space 22 can effectively increase the throttling of the refrigerant by the shell and tube heat exchanger. Sparkling effect.

One end of the throttle plate 21 is provided with a throttle hole 211 , and the throttle holes 211 on two adjacent throttle plates 21 are arranged in a staggered manner. For example, among two adjacent throttle plates 21 , the throttle hole 211 is provided at the first end of one throttle plate 21 , and the throttle hole 211 is provided at the second end of the other throttle plate 21 . The orifice 211. That is to say The flow path of the refrigerant between the throttle plates 21 is S-shaped, and the throttling flow path of the refrigerant is increased as much as possible in a certain space, thereby increasing the throttling effect of the refrigerant.

All the throttle plates 21 include at least a second throttle plate 212 located at the lowest level. The second throttle plate 212 is formed with an inclined portion 213 at an angle with the horizontal plane. The throttle hole 211 is provided on on the inclined portion 213. The inclined portion 213 is used to further achieve the effect of gas-liquid separation. The liquid refrigerant will flow along the inclined portion 213 under the action of gravity, while the gaseous refrigerant will remain above the liquid refrigerant, thereby achieving gas-liquid separation. At the same time, arranging the orifice 211 at the inclined portion 213 can make the liquid phase refrigerant flow downward through the orifice 211 as much as possible, further increasing the gas-liquid separation effect.

Along the width direction of the second throttle plate 212, the second throttle plate 212 includes a planar portion 214 and an inclined portion 213 arranged side by side. There is a gap between the planar portion 214 and the adjacent throttle plate 21. There is a spacing for refrigerant to circulate, and the spacing between the inclined portion 213 and the adjacent throttle plate 21 gradually increases in the direction away from the flat portion 214 .

The housing 1 is provided with an air supply port 102, and the air supply port 102 is connected to the gap. Although the gaseous refrigerant that has been separated from gas and liquid by the throttle plate 21 at least once still contains liquid refrigerant, the amount of liquid refrigerant is relatively small and can already meet the requirements for air replenishment of the compressor. Therefore, The air supply port 102 can be disposed at this interval and the gaseous refrigerant within this interval can be used to supply air to the compressor.

The flash structure 2 also includes a filtrate plate 23, which is disposed on the inclined portion 213. The filtrate plate 23 is provided with filtrate holes 231, and the filtrate plate 23 and part of the inclined portion 213 and the corresponding housing 1 together form a liquid accumulation space 24, and the filtrate plate 23, part of the inclined portion 213, the adjacent throttle plate 21 and the corresponding housing 1 together form a The first gas-liquid separation space 22. The filtrate plate 23 is used to further separate the refrigerant above the second throttle plate 212. After the larger droplets contact the filtrate plate 23, they pass through the filtrate holes 231 and gather in the liquid accumulation space 24 under the action of air blowing. And a liquid phase refrigerant with a certain liquid level is formed in the liquid accumulation space 24. The filtrate plate 23 can reduce the disturbance of the gas phase refrigerant on the liquid surface, thereby forming a liquid phase at the orifice 211 of the second throttle plate 212. seal to ensure the stable operation of the orifice 211.

The flash structure 2 also includes a plurality of baffles 25 , all of which are staggeredly arranged in the first gas-liquid separation space 22 . Multiple baffles 25 are used to increase the flow distance of the refrigerant in the first gas-liquid separation space 22 as much as possible. At the same time, when the refrigerant hits the baffles 25, small refrigerant droplets will Condensation into large droplets, thereby achieving gas-liquid separation.

All the baffles 25 are arranged staggered up and down. Make full use of the refrigerant's own gravity for liquid separation to increase the liquid separation effect. Preferably, there are upper baffles and lower baffles arranged at intervals.

The liquid separation structure 3 includes a flow plate 31, and all the throttle plates 21 include a second throttle plate 212 located at the bottom, and the flow plate 31 is arranged below the second throttle plate 212, And the second gas-liquid separation space 26 is enclosed between the flow plate 31 , the second throttle plate 212 and the corresponding housing 1 . The gas-liquid two-phase refrigerant enters the second gas-liquid separation space 26. When the small droplets flow downward, they hit the flow plate 31 and condense into large droplets, thereby achieving gas-liquid collision separation. At the same time, the liquid droplets naturally settle to the bottom of the second gas-liquid separation space 26 by gravity, thereby realizing gravity separation of gas and liquid.

The overflow plate 31 is provided with an overflow hole 311, and the overflow hole 311 is offset from the orifice 211 on the second throttle plate 212 to increase the flow distance of the refrigerant as much as possible. Preferably, the second end of the second throttle plate 212 is provided with a throttle hole 211 , and the flow hole 311 is located at a position opposite to the first end of the second throttle plate 212 .

Specifically, the number of through-flow holes 311 is multiple.

The shell and tube heat exchanger includes a side baffle 4, which is located below the second throttle plate 212, on one side of the flow plate 31, and on the side. On the first side of the baffle 4, the flow plate 31, the second throttle plate 212 and part of the side baffles 4 together form the second gas-liquid separation space 26. On the side On the second side of the baffle 4 , the side baffle 4 and the corresponding housing 1 form an exhaust area 103 . The side baffles 4 can be used to resist and collect liquid droplets splashed during the falling film evaporation process, and at the same time, it is convenient to directly send the gaseous refrigerant in the second gas-liquid separation space 26 to the exhaust area 103 to prevent the gaseous refrigerant from entering the separation chamber. The liquid structure 3 and the heat exchange tube area improve the liquid separation effect of the liquid separation structure 3 and the heat exchange effect of the heat exchange tube.

The side baffle 4 is provided with an air outlet 41 , and the second gas-liquid separation space 26 and the exhaust area 103 are connected through the air outlet 41 .

A filtering mechanism 5 is provided at the air outlet 41 . The filtering mechanism 5 is used to filter the airflow entering the exhaust area 103 through the air outlet 41 so that the liquid droplets carried in the airflow come into contact with the filtering mechanism 5 and form large droplets under the adsorption effect of the filtering mechanism 5 and then drip to the third In the second gas-liquid separation space 26, the purpose of gas-liquid filter separation is achieved, and ultimately the reliability of the gaseous refrigerant in the exhaust area 103 is ensured.

The flow plate 31 is provided with a flow hole 311 , and the air outlet 41 is located above the flow hole 311 . It is convenient for the large droplets formed by the filtering mechanism 5 to directly enter the liquid separation structure 3 for liquid separation after dropping into the second gas-liquid separation space 26, so as to avoid the large droplets being taken away by the air flow again and affecting the filtration effect of the filtering mechanism 5. .

Preferably, the filtering mechanism 5 includes a gas-liquid filter.

The housing 1 is provided with an exhaust port 104 , and an air baffle 42 is provided between the air outlet 41 and the exhaust port 104 . The gas stroke from the air outlet 41 to the exhaust port 104 is increased to form a "U"-shaped air passage, thereby reducing the risk of suction liquid in the compressor.

The shell and tube heat exchanger also includes a plurality of heat exchange tubes 6. All the heat exchange tubes 6 are arranged below the liquid separation structure 3, and all the heat exchange tubes 6 are located on the side. The first side of the baffle 4. Make full use of the side baffles 4 to form a "U" shaped air channel (second gas-liquid separation space 26 - liquid separation structure 3 - heat exchange structure - exhaust area 103), increasing the gaseous state formed after the liquid refrigerant absorbs heat The refrigerant stroke reduces the risk of compressor suction liquid.

The liquid separation structure 3 also includes at least two liquid separation plates 32. All the liquid separation plates 32 are arranged side by side below the flow plate 31, and the uppermost liquid separation plate 32 and the flow plate 31 are arranged in parallel. A liquid separation space 33 is formed between two adjacent liquid separation plates 32 . By arranging multiple liquid separation plates 32, the liquid separation effect of the liquid separation structure 3 is further increased. The liquid refrigerant passes through multiple liquid separation spaces 33 in sequence, thereby achieving uniform liquid separation. In particular, the liquid refrigerant forms a stable liquid seal above the liquid separation hole. The refrigerant state is the same at different locations and there is no airflow blowing around the liquid level. Therefore, the liquid refrigerant is separated through the liquid separation hole only under the action of gravity. At the same time, it is also avoided that the gas-liquid two-phase refrigerant is mixed and separated, and the flow rate is too high and is sprayed onto the outer wall of the heat exchange tube 6, affecting the film distribution effect.

The liquid separation plates 32 are provided with liquid separation holes 321, and the liquid separation holes 321 on two adjacent liquid separation plates 32 are staggered to increase the liquid separation effect.

Specifically, in the two adjacent layers of liquid separation plates 32, the axis of the liquid separation hole 321 on the upper layer of liquid separation plate 32 and the axis of the liquid separation hole 321 on the lower layer of liquid separation plate 32 are not collinear, and can be in the horizontal direction. There is spacing in the x-direction and/or y-direction.

The flash structure 2 includes at least two throttle plates 21, and the liquid separation structure 3 also includes at least two liquid separation plates 32. The throttle plate 21 in the uppermost layer and the liquid separation plate in the lowermost layer are A side sealing plate 7 is connected between the edges of the plate 32 on the same side, and the side sealing plate 7 is arranged in conformity with the corresponding part of the housing 1 . The side sealing plate 7 is used to make the flash structure 2 and the liquid separation structure 3 form a whole. At the same time, the side sealing plate 7 can further increase the sealing effect of the flash structure 2 and the liquid separation structure 3, and avoid the flash structure 2 and the liquid separation structure. 3 all need to be directly sealed with the inner surface of the housing 1, which increases the difficulty of processing.

In particular, the shell and tube heat exchanger also includes side sealing plates. The side sealing plates are arranged parallel to the baffles 25, and the side sealing plates are opposite to the first ends of all throttle plates 21 and all liquid separation plates 32. The first end is sealed to increase the sealing effect of the flash structure 2 and the liquid separation structure 3, and avoid the need for the flash structure 2 and the liquid separation structure 3 to be directly sealed with the inner surface of the housing 1, thereby increasing processing difficulty.

Example

Take the flash structure 2 including two throttling plates 21 and the liquid separation structure 3 including two liquid separation plates 32 as an example:

Along the direction away from the refrigerant inlet 101, the two throttle plates 21 are respectively a primary throttle plate and a secondary throttle plate (second throttle plate 212), and the two liquid separation plates 32 are respectively a primary liquid separation plate. and secondary separator plates.

The refrigerant inlet 101 is provided with a liquid inlet pipe, the air supply port 102 is provided with an air supply pipe, and the exhaust port 104 is provided with an exhaust pipe.

The high-temperature and high-pressure liquid refrigerant discharged from the condenser enters the evaporator through the liquid inlet pipe on the upper part of the shell 1. The refrigerant flows downward through the first-level throttle hole on the first-level throttle plate to achieve throttling and decompression and converts it into gas and liquid. Mutually. The primary orifice is located at one axial end of the heat exchanger. The gas-liquid two-phase refrigerant enters the first gas-liquid separation space 22. The first gas-liquid separation space 22 consists of a primary throttling plate at the top, a secondary throttling plate at the bottom, axial side seals, circumferential It is composed of the side sealing plate 7 and the inner wall surface of the housing 1. For example, the first gas-liquid separation space 22 is provided with baffles 25 staggered up and down along the axial direction of the heat exchanger. The gas-liquid two-phase refrigerant passes through the upper baffle and the lower baffle, and the gas-liquid separation is achieved through collision. The secondary throttling plate is bent into an inclined downward structure at one end in the circumferential direction, and a secondary throttling hole is provided at the lower axial end. At the same time, a horizontally placed filtrate plate 23 is set at the middle height of the inclined surface. The filtrate plate 23 Process the filtrate hole 231. Therefore, the bottom of the filtrate plate 23, the secondary throttling plate, the side sealing plate 7, and the side sealing plates form a liquid accumulation space 24. The liquid accumulation space 24 is located at the bottom of the first gas-liquid separation space 22. Therefore, the liquid refrigerant moves under the action of gravity and They are gathered here under the influence of airflow. In the first gas-liquid separation space 22, the gas-liquid two-phase refrigerant flows along the axial direction of the housing 1. When passing through the upper baffle and the lower baffle, the two-phase refrigerant collides with them and the flow direction changes, and the small liquid The drops will condense into large droplets. On the one hand, they will drip downward along the baffle 25 and the side sealing plate 7. On the other hand, when the large droplets flow axially, they will gradually settle at the bottom of the space under the action of gravity. Finally, the large droplets will Contact the top of the filtrate plate 23 and gather into the liquid accumulation space 24 through the filtrate holes 231 under the action of air blowing. The liquid refrigerant in the liquid space 24 forms a certain liquid level, and the filtrate plate 23 can reduce the gas phase refrigerant from disturbing the liquid level, thereby forming a liquid seal at the secondary orifice, allowing the orifice 211 to operate stably. The primary and secondary orifices are placed at both axial ends of the heat exchanger, making full use of the axial length of the heat exchanger to increase the refrigerant flow stroke and enhance the gas-liquid separation effect. At the same end of the secondary orifice in the axial direction of the heat exchanger and at the other end in the circumferential direction, an air supply pipe is provided on the casing 1 to guide the gas phase refrigerant separated after passing through the first gas-liquid separation space 22 into the compressor for air supply. .

The two-phase refrigerant after secondary throttling enters the second gas-liquid separation space 26. The second gas-liquid separation space 26 consists of a secondary throttling plate at the top, a flow plate 31 at the bottom, a circumferential air outlet plate, an axial It consists of side sealing panels. An air outlet is processed at an end of the side sealing plate away from the secondary orifice and at a higher position. At the same time, a gas-liquid filter (filter mechanism 5) is provided around the air outlet in the second gas-liquid separation space 26. On the flow plate An overflow hole 311 is formed on the end of 31 away from the secondary throttle hole. The two-phase refrigerant enters the second gas-liquid separation space 26. When the small droplets flow downward, they hit the flow plate 31 and condense into large droplets, thereby achieving gas-liquid collision separation. At the same time, the liquid droplets naturally settle to the bottom of the second gas-liquid separation space 26 using gravity in the large space, thereby realizing gravity separation of gas and liquid. When the airflow carries a small number of small droplets to the air outlet located at a higher position, they come into contact with the gas-liquid filter. The small droplets form large droplets under the adsorption of the gas-liquid filter. It drips to the bottom of the second gas-liquid separation space 26 to achieve gas-liquid filter separation. Finally, the liquid droplets pass through the overflow hole 311 under the blowing effect of the axial flow airflow, and the refrigerant gas enters the heat exchange space of the heat exchanger through the air outlet hole.

The liquid refrigerant enters the first-level liquid separation space 33 through the overflow hole 311, and the bottom is a first-level liquid separation plate. The primary liquid separation plate is processed with evenly distributed liquid separation holes 321 along the axial and circumferential directions of the heat exchanger. The liquid refrigerant enters the secondary liquid separation space through the liquid separation holes 321 of the primary liquid separation plate. The bottom is the secondary liquid separation space. The liquid separation plate and the secondary liquid separation plate are also processed with liquid separation holes 321 evenly distributed along the axial and circumferential directions of the heat exchanger. In the primary and secondary liquid separation spaces, the liquid refrigerant forms a stable liquid seal above the liquid separation hole 321. The refrigerant state is the same in different positions and there is no airflow blowing around the liquid level. Therefore, the liquid only passes through the liquid separation hole under the action of gravity. 321 for dispensing. At the same time, it is also avoided that the gas-liquid two-phase refrigerant is mixed and separated, and the flow rate is too high and is sprayed onto the outer wall of the heat exchange tube 6, affecting the film distribution effect. The liquid separation holes 321 on the two-layer liquid separation plates 32 are staggered along the axial and circumferential directions to enhance the liquid separation effect.

An air conditioning unit includes the above-mentioned shell and tube heat exchanger.

The above-described embodiments only express several implementation modes of the present disclosure, and their descriptions are relatively specific and detailed, but should not be understood as limiting the patent scope of the present disclosure. It should be noted that, for those of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present disclosure, and these all fall within the protection scope of the present disclosure. Therefore, the protection scope of the patent disclosed should be determined by the appended claims.

Claims

A shell and tube heat exchanger, including a shell (1) and a flash structure (2) and a liquid separation structure (3) arranged in the shell (1). The shell (1) is provided with There is a refrigerant inlet (101), and the liquid separation structure (3) is arranged on the side of the flash structure (2) away from the refrigerant inlet (101), and enters from the refrigerant inlet (101). The refrigerant flows through the flash structure (2) and the liquid separation structure (3) in sequence.
The shell and tube heat exchanger according to claim 1, wherein the flash structure (2) includes at least two throttling plates (21), all of the throttling plates (21) along the edge away from the refrigerant inlet. (101) are arranged side by side in the housing (1), and between the uppermost throttle plate (21) and the corresponding housing (1) and between the two adjacent throttle plates A first gas-liquid separation space (22) is enclosed between the plate (21) and the corresponding shell (1), and the refrigerant entering from the refrigerant inlet (101) flows through all the first gas-liquid separation spaces in sequence. Gas-liquid separation space (22).
The shell and tube heat exchanger according to claim 2, wherein one end of the throttle plate (21) is provided with a throttle hole (211), and the two adjacent throttle plates (21) are provided with a throttle hole (211). The orifices (211) are arranged in a staggered manner.
The shell and tube heat exchanger according to claim 2 or 3, wherein all the throttle plates (21) include at least a second throttle plate (212) located at the bottom, and the second throttle plate (212) An inclined portion (213) having an angle with the horizontal plane is formed on the 212), and the orifice (211) is provided on the inclined portion (213).
The shell and tube heat exchanger according to claim 4, wherein along the width direction of the second throttle plate (212), the second throttle plate (212) includes planar portions (214) arranged side by side and The inclined portion (213), the flat portion (214), the inclined portion (213) and the adjacent throttle plate (21) each have a gap for refrigerant circulation, and are arranged along the direction away from the plane. In the direction of the portion (214), the size of the gap between the inclined portion (213) and the adjacent throttle plate (21) gradually increases.
The shell and tube heat exchanger according to claim 5, wherein the housing (1) is provided with an air supply port (102), and the air supply port (102) is connected with the gap.
The shell and tube heat exchanger according to any one of claims 4 to 6, wherein the flash structure (2) further includes a filtrate plate (23), the filtrate plate (23) is arranged on the inclined part (213), the filtrate plate (23) is provided with a filtrate hole (231), and the filtrate plate (23), part of the inclined portion (213) and the corresponding housing (1) collectively surround forming a liquid accumulation space (24) located below the filtrate plate (23), the filtrate plate (23), part of the inclined portion (213), the adjacent throttle plate (21) and all corresponding The housings (1) together form a first gas-liquid separation space (22) located above the filtrate plate (23).
The shell and tube heat exchanger according to claim 7, wherein the flash structure (2) further includes a plurality of baffles (25), all of the baffles (25) are staggeredly arranged on the first In the gas-liquid separation space (22).
The shell and tube heat exchanger according to any one of claims 2 to 8, wherein the liquid separation structure (3) includes a flow plate (31), and all of the throttle plates (21) include a flow plate located at the lowest layer. The second throttle plate (212), the flow plate (31) is arranged below the second throttle plate (212), and the flow plate (31), the second throttle plate A second gas-liquid separation space (26) is enclosed between (212) and the corresponding housing (1).
The shell and tube heat exchanger according to claim 9, wherein the flow plate (31) is provided with a flow hole (311), and the flow hole (311) is connected with the second throttle plate (311). The orifice (211) on the 212) is misaligned.
The shell and tube heat exchanger according to claim 9 or 10, which includes a side baffle (4) located on the second throttle plate. (212), one side of the flow plate (31), and on the first side of the side baffle (4), the flow plate (31), the second throttle plate (212) and part of the side baffles (4) together form the second gas-liquid separation space (26). On the second side of the side baffles (4), the side baffles (4) (4) The exhaust area (103) is formed with the corresponding housing (1).
The shell and tube heat exchanger according to claim 11, wherein the side baffle (4) is provided with an air outlet (41), and the second gas-liquid separation space (26) and the exhaust area (103) communicates through the air outlet (41).
The shell and tube heat exchanger according to claim 12, wherein a filtering mechanism (5) is provided at the air outlet (41).
The shell and tube heat exchanger according to claim 12 or 13, wherein the flow plate (31) is provided with a flow hole (311), and the air outlet (41) is located in the flow hole (311). ) above.
The shell and tube heat exchanger according to any one of claims 12 to 14, wherein the housing (1) is provided with an exhaust port (104), the air outlet (41) and the exhaust port An air baffle (42) is provided between the ports (104).
The shell and tube heat exchanger according to any one of claims 11 to 15, the shell and tube heat exchanger further includes a plurality of heat exchange tubes (6), all of the heat exchange tubes (6) are provided with Below the liquid separation structure (3), all the heat exchange tubes (6) are located on the first side of the side baffle (4).
The shell and tube heat exchanger according to any one of claims 9 to 16, wherein the liquid separation structure (3) further includes at least two liquid separation plates (32), all of the liquid separation plates (32) The two adjacent liquid separation plates are arranged side by side below the flow plate (31), between the uppermost liquid separation plate (32) and the current flow plate (31). A liquid separation space (33) is formed between (32).
The shell and tube heat exchanger according to claim 17, wherein the liquid separation plate (32) is provided with a liquid separation hole (321), and the liquid separation holes (321) on two adjacent liquid separation plates (32) are (321) Staggered settings.
The shell and tube heat exchanger according to any one of claims 1 to 18, wherein the flash structure (2) includes at least two throttle plates (21), and the liquid separation structure (3) further includes There are at least two liquid separation plates (32). A side sealing plate (7) is connected between the edges of the uppermost throttle plate (21) and the lowermost liquid separation plate (32) on the same side. , the side sealing plate (7) and the corresponding part of the casing (1) are arranged in profile.
An air conditioning unit, characterized by comprising the shell-and-tube heat exchanger according to any one of claims 1 to 19.