Evaporative cooling devices, outdoor units and air conditioning systems

Abstract

The present application provides an evaporative cooling device, an outdoor unit and an air conditioning system. The evaporative cooling device comprises a heat exchanger (6), a wet curtain cooling device and a falling film spraying device (9), wherein the wet curtain cooling device is arranged on the windward side of the heat exchanger (6), and the falling film spraying device (9) is arranged above the heat exchanger (6). After the coolant enters the wet curtain cooling device for filtration, it enters the falling film spraying device (9) to cool the heat exchanger (6). According to the evaporative cooling device of the present application, the heat exchange effect of the heat exchanger can be effectively improved, the air conditioning energy efficiency ratio can be improved, and at the same time, the scaling phenomenon on the surface of the heat exchanger can be effectively reduced.

Description

Technical Field

[0001] The present application relates to the technical field of air conditioning, and in particular to an evaporative cooling device, an outdoor unit and an air conditioning system. Background Art

[0002] Most air conditioner outdoor heat exchangers are air-cooled, and the outdoor heat exchanger uses air as the cooling source. When the outdoor ambient temperature rises, the condensing pressure of the air conditioning system will also increase, the performance of the air conditioning unit will decrease, and the energy consumption will increase. In order to obtain the same cooling capacity, the capacity of the refrigeration compressor needs to be increased; another prominent problem is that the heat transfer coefficient of the air-cooled condenser is small, which results in high operating costs and equipment costs.

[0003] Nowadays, evaporative cooling technology is widely used in the field of refrigeration as one of the means of high energy efficiency. There are three types of traditional evaporative condensers: spray type, wet curtain type and falling film type. The spray type uses a nozzle or a nozzle to spray cooling water, and the water mist evaporates and absorbs the heat of the surrounding environment of the heat exchanger to improve the heat exchange effect of the condenser. However, this method causes a large amount of water consumption and the utilization rate of cooling water is low. The wet curtain type uses a water pump to transport water to the top of the water curtain, and absorbs heat through the evaporation of the water curtain, reduces the temperature of the surrounding air, and enhances heat exchange. However, in this way, the water curtain is arranged on the windward side of the heat exchanger, which increases the wind resistance. Falling film evaporation sprinkles water droplets on the external unit condenser, and uses the latent heat of water evaporation to enhance the heat exchange of the condenser. In this way, water is in direct contact with the heat exchanger, and the surface of the heat exchanger is prone to scaling. Summary of the invention

[0004] Therefore, the technical problem to be solved by the present application is to provide an evaporative cooling device, an outdoor unit and an air-conditioning system, which can effectively improve the heat exchange effect of the heat exchanger, improve the air-conditioning energy efficiency ratio, and effectively reduce scaling on the surface of the heat exchanger.

[0005] In order to solve the above problems, the present application provides an evaporative cooling device, including a heat exchanger, a wet curtain cooling device and a falling film cooling device. The wet curtain cooling device is arranged on the windward side of the heat exchanger, and the falling film cooling device is arranged above the heat exchanger. After the coolant enters the wet curtain cooling device for filtration, it enters the falling film cooling device to cool the heat exchanger.

[0006] Preferably, the wet curtain cooling device comprises a wet curtain and a wet curtain spraying device, wherein the wet curtain spraying device is arranged above the wet curtain and supplies cooling liquid to the wet curtain.

[0007] Preferably, the heat exchanger packs a subcooling section, and a wet curtain is arranged at the front air inlet side of the subcooling section, and the height of the wet curtain is less than or equal to the height of the subcooling section.

[0008] Preferably, the height of the wet curtain is equal to the height of the supercooling section.

[0009] Preferably, the heat exchanger comprises a gas phase region, a gas-liquid two-phase region and a liquid phase region, and the supercooling section is the liquid phase region.

[0010] Preferably, a first liquid storage box for collecting the cooling liquid of the wet curtain cooling device is arranged at the bottom of the wet curtain cooling device, and a second liquid storage box for collecting the cooling liquid of the falling film cooling device is arranged at the bottom of the falling film cooling device. The first liquid storage box and the second liquid storage box are spaced apart, the second liquid storage box supplies liquid to the wet curtain cooling device, and the first liquid storage box supplies liquid to the falling film cooling device.

[0011] Preferably, the first liquid storage box is connected to the falling film cooling device via a first liquid supply pipeline, and a first pump is provided on the first liquid supply pipeline.

[0012] Preferably, the second liquid storage box is connected to the wet curtain cooling device via a second liquid supply pipeline, and a second pump is provided on the second liquid supply pipeline.

[0013] Preferably, a water replenishment pipeline is provided on the second liquid storage box.

[0014] Preferably, a control valve is provided on the water supply pipeline.

[0015] According to another aspect of the present application, an outdoor unit is provided, comprising an evaporative cooling device, which is the evaporative cooling device described above.

[0016] According to another aspect of the present application, an air conditioning system is provided, including an indoor unit, an outdoor unit, a compressor and a throttling device, wherein the outdoor unit is the outdoor unit described above, and the compressor, the outdoor unit, the throttling device and the indoor unit are arranged in sequence.

[0017] The evaporative cooling device provided by the present application includes a heat exchanger, a wet curtain cooling device and a falling film cooling device. The wet curtain cooling device is arranged on the windward side of the heat exchanger, and the falling film cooling device is arranged above the heat exchanger. After the coolant enters the wet curtain cooling device for filtration, it enters the falling film cooling device to perform falling film cooling on the heat exchanger. The evaporative cooling device adopts a combination of wet curtain and falling film, the wet curtain cooling device is arranged on the windward side of the heat exchanger, and the falling film spray device is arranged above the heat exchanger. The wet curtain cooling device can be used to reduce the temperature of the air passing through the heat exchanger, increase the supercooling degree of the heat exchanger, and improve the refrigeration effect. At the same time, the falling film spray device can be used to spray the coolant on the heat exchanger, and the coolant absorbs heat to reduce the surface temperature of the heat exchanger, so as to enhance the heat exchange of the heat exchanger, reduce the condensation temperature, and improve the system energy efficiency. In addition, the coolant first passes through the wet curtain cooling device to filter out most of the impurities and then flows through the surface of the heat exchanger through the falling film cooling device, which can effectively reduce the blockage of the spray hole and the scaling of the heat exchanger surface, and improve the operating reliability of the air conditioning system. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1This is a schematic structural diagram of an evaporative cooling device according to an embodiment of the present application;

[0019] Figure 2 This is a schematic diagram of the structure of an outdoor unit according to an embodiment of the present application;

[0020] Figure 3 This is a schematic structural diagram of a heat exchanger according to an embodiment of the present application;

[0021] Figure 4 A liquid flow system diagram of an evaporative cooling device according to an embodiment of the present application;

[0022] Figure 5 This is an air conditioning system operation diagram of an embodiment of the present application.

[0023] The reference numerals are:

[0024] 1. Compressor; 2. Outdoor unit; 3. Throttling device; 4. Indoor unit; 5. Fan; 6. Heat exchanger; 7. Wet curtain; 8. Wet curtain spray device; 9. Falling film spray device; 10. First pump; 11. Second pump; 12. First liquid storage box; 13. Second liquid storage box; 14. Heat exchange tube; 15. Fin; 16. Control valve; 17. Gas phase region; 18. Gas-liquid two-phase region; 19. Liquid phase region. DETAILED DESCRIPTION

[0025] See also Figures 1 to 5 As shown, according to an embodiment of the present application, the evaporative cooling device includes a heat exchanger 6, a wet curtain cooling device and a falling film spray device 9. The wet curtain cooling device is arranged on the windward side of the heat exchanger 6, and the falling film spray device 9 is arranged above the heat exchanger 6. After the coolant enters the wet curtain cooling device for filtration, it enters the falling film spray device 9 to perform falling film cooling on the heat exchanger 6.

[0026] The evaporative cooling device adopts a combination of wet curtain and falling film. The wet curtain cooling device is arranged on the windward side of the heat exchanger 6, and the falling film spray device 9 is arranged above the heat exchanger 6. The wet curtain cooling device can be used to reduce the temperature of the air passing through the heat exchanger 6, increase the supercooling degree of the heat exchanger 6, and improve the refrigeration effect. At the same time, the falling film spray device 9 can be used to spray the coolant on the heat exchanger 6, and the coolant absorbs heat to reduce the surface temperature of the heat exchanger 6, thereby enhancing the heat exchange of the heat exchanger 6, reducing the condensation temperature, and improving the system energy efficiency. In addition, the coolant first passes through the wet curtain cooling device to filter out most of the impurities, and then flows through the surface of the heat exchanger 6 through the falling film spray device 9, which can effectively reduce the clogging of the spray hole and the scaling of the surface of the heat exchanger 6, thereby improving the operating reliability of the air-conditioning system.

[0027] In one embodiment, the wet curtain cooling device includes a wet curtain 7 and a wet curtain spraying device 8 . The wet curtain spraying device 8 is disposed above the wet curtain 7 and supplies cooling liquid to the wet curtain 7 .

[0028] The above-mentioned coolant is, for example, water, or other liquids capable of cooling down.

[0029] The material of the wet curtain 7 is similar to a porous medium. Water flows from top to bottom, forming a water film on the surface of the wet curtain 7, increasing the heat exchange area and ensuring a good cooling effect. Impurities in the water will be blocked at the wet curtain 7. When the water filtered by the wet curtain 7 reaches the falling film spray device 9, the impurity content in the water is reduced. The water outlet of the falling film spray device 9 is generally a small hole with a hole diameter of less than 2mm, which reduces the clogging of the falling film spray device 9.

[0030] In one embodiment, the heat exchanger 6 forms a subcooling section, and the wet curtain 7 is arranged at the front air inlet side of the subcooling section, and the height of the wet curtain 7 is less than or equal to the height of the subcooling section.

[0031] In one embodiment, the height of the wet curtain 7 is equal to the height of the supercooling section.

[0032] The heat exchanger 6 comprises a gas phase region 17 , a gas-liquid two-phase region 18 and a liquid phase region 19 , and the subcooling section is the liquid phase region 19 .

[0033] In this embodiment, the wet curtain 7 is only set for the supercooling section to cool down the gas passing through the supercooling section. The refrigerant in the supercooling section is liquid, and the heat transfer coefficient of the liquid area has a greater impact on heat transfer than the two-phase area. The wet curtain 7 is set in the supercooling section to effectively improve the heat transfer coefficient of the liquid area, and the wind resistance ratio is much smaller than that of the whole heat exchanger with a wet curtain.

[0034] In other embodiments, the wet curtain 7 may also be arranged relative to the entire heat exchanger.

[0035] In one embodiment, a first liquid storage box 12 for collecting the cooling liquid of the wet curtain cooling device is provided at the bottom of the wet curtain cooling device, and a second liquid storage box 13 for collecting the cooling liquid of the falling film spray device 9 is provided at the bottom of the falling film spray device 9. The first liquid storage box 12 and the second liquid storage box 13 are separated, the second liquid storage box 13 supplies liquid to the wet curtain cooling device, and the first liquid storage box 12 supplies liquid to the falling film spray device 9.

[0036] The water sprayed by the wet curtain spray device 8 flows through the wet curtain 7, flows down along the wet curtain 7, and falls into the first liquid storage box 12 for storage. The water in the first liquid storage box 12 is the water filtered by the wet curtain 7. Therefore, water can be supplied to the falling film spray device 9 by the first liquid storage box 12, thereby reducing the possibility of clogging of the spray holes of the falling film spray device 9 and scaling on the surface of the heat exchanger 6.

[0037] A fan 5 is arranged on the leeward side of the heat exchanger 6. The fan 5 uses suction to provide air flow power, which will not form an obstacle on the air inlet side of the heat exchanger 6, and can ensure that the heat exchanger 6 has a larger heat exchange area and improve the heat exchange efficiency.

[0038] The water sprayed by the falling film spray device 9 onto the surface of the heat exchanger 6 exchanges heat with the heat exchanger 6, and then flows downward along the heat exchanger 6 to the second liquid storage box 13. While flowing through the surface of the heat exchanger 6, the water can clean the surface of the heat exchanger 6. After reaching the second liquid storage box 13, cooling water can be supplied to the wet curtain cooling device, and the filtering effect of the wet curtain cooling device can be used to reduce the impact of the cooling water on the cooling system after cleaning the surface of the heat exchanger 6.

[0039] In this embodiment, cooling water is sprayed on the wet curtain 7 through the wet curtain spray device 8, and the water on the wet curtain 7 after heat exchange with the wind flows to the first liquid storage box 12 below. Subsequently, the water is pumped to the falling film spray device 9 and then sprayed on the heat exchanger 6 for heat exchange. The water heated by heat exchange flows into the second liquid storage box 13 at the bottom of the outdoor unit, and the condensed water is pumped to the wet curtain spray device 8 again by the pump, forming a cycle.

[0040] In one embodiment, the first liquid storage box 12 is connected to the falling film spraying device 9 via a first liquid supply pipeline, and a first pump 10 is provided on the first liquid supply pipeline.

[0041] In one embodiment, the second liquid storage box 13 is connected to the wet curtain cooling device via a second liquid supply pipeline, and a second pump 11 is provided on the second liquid supply pipeline.

[0042] In one embodiment, a water replenishment pipeline is provided on the second liquid storage box 13, which can replenish water to the second liquid storage box 13 to avoid the problem of insufficient cooling water.

[0043] In one embodiment, a control valve 16 is provided on the water supply pipeline, which can control the on-off of the water supply pipeline, thereby controlling the cooling water supply of the second liquid storage box 13 .

[0044] The working process of the evaporative cooling device is as follows:

[0045] When the system is in refrigeration mode, the cooling water enters the second liquid storage box 13 through the water replenishment port, and the water is sent to the wet curtain spray device 8 by the first pump 10 and then flows into the wet curtain 7. The flow process of the refrigerant in the heat exchange tube 14 of the heat exchanger 6 goes through three stages: the gas phase zone, the gas-liquid two-phase zone and the liquid phase zone. The area where the refrigerant is in the liquid phase is called the supercooling section. The difference between the outlet temperature of the supercooling section of the heat exchanger 6 and the condensation temperature is the supercooling degree. The height of the wet curtain 7 is the same as the height of the supercooling section of the heat exchanger 6. The cooling water fully exchanges heat with the outside air in the wet curtain 7, and the low-temperature air after heat exchange exchanges heat with the surface of the heat exchanger fin 15. The wet curtain evaporative cooling increases the heat exchange temperature difference and heat exchange coefficient of the supercooling section of the heat exchanger 6, and at the same time increases the outlet supercooling degree of the heat exchanger 6, effectively improving the heat exchange capacity of the heat exchanger 6 and enhancing the refrigeration effect of the system. At the same time, the water passes through the wet curtain 7 to filter out small particles of impurities, which purifies the water. The water passing through the wet curtain 7 flows downward into the first liquid storage box 12 at the bottom, and is sent to the falling film spray device 9 by the second pump 11 .

[0046] In the falling film evaporation form, water generally flows out through the small holes or narrow slits provided in the falling film spray device 9. Impurities in the water are easily gathered in the small holes or narrow slits, causing the spray device to be blocked. In the present application, the water flowing into the falling film spray device 9 is filtered out by the wet curtain 7 to remove the impurities that are easy to be blocked, thereby reducing the possibility of clogging of the spray hole and increasing the service life of the spray device. In addition, in the falling film evaporative cooling process, water is in direct contact with the surface of the heat exchanger 6. After running for a period of time, scale will be generated on the surface of the heat exchanger 6. The water filtered by the wet curtain 7 also reduces the scale on the surface of the heat exchanger 6.

[0047] The water flowing out of the falling film spray device 9 flows from top to bottom on the surface of the heat exchanger 6 in a uniform film. During the flow, the water film absorbs the heat of the heat exchanger 6 and evaporates, reducing the temperature of the surface of the heat exchanger 6, strengthening the heat exchange between the heat exchanger 6 and the air, and improving the cooling effect of the system. The unevaporated water flows into the second liquid storage box 13 at the bottom through the heat exchanger 6, and the second pump 11 delivers the water to the wet curtain spray device 8, thereby forming a cycle. In addition, a water replenishment port is provided on the side of the second liquid storage box 13. If there is a lack of water in the system, the control valve 16 can be used to control the replenishment of water into the system.

[0048] According to an embodiment of the present application, the outdoor unit includes an evaporative cooling device, which is the evaporative cooling device mentioned above.

[0049] According to an embodiment of the present application, the air-conditioning system includes an indoor unit 4, an outdoor unit 2, a compressor 1 and a throttling device 3, wherein the outdoor unit 2 is the above-mentioned outdoor unit 2, and the compressor 1, the outdoor unit 2, the throttling device 3 and the indoor unit 4 are arranged in sequence.

[0050] During the operation of the air conditioning system, the compressor 1 continuously draws the refrigerant gas generated in the evaporator, compresses the refrigerant gas to produce high-temperature and high-pressure refrigerant gas, and sends it to the outdoor unit heat exchanger to exchange heat with the air. In this application, a spray device is arranged above the heat exchanger 6 of the outdoor unit, and the spray liquid is distributed on the surface of the heat exchanger 6 in a film-forming manner. The evaporation of water absorbs heat to reduce the surface temperature of the heat exchanger, enhance the heat exchange effect, and reduce the condensation temperature at the same time, effectively improving the energy efficiency ratio of the air conditioner. In addition, a wet curtain 7 is arranged on the windward side of the supercooling section of the heat exchanger 6 to exchange heat with the air, reduce the air temperature, and enhance the heat exchange effect of the supercooling section. The refrigerant liquid condensed in the heat exchanger 6 of the outdoor unit is cooled and depressurized by the throttling device 3 to become a gas-liquid mixture, and enters the evaporator of the indoor unit 4. The liquid in the mixture evaporates in the evaporator, absorbs heat to become a refrigerant gas and returns to the compressor 1, forming a circulating flow.

[0051] It is easy for those skilled in the art to understand that, under the premise of no conflict, the above-mentioned advantageous methods can be freely combined and superimposed.

[0052] The above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application shall be included in the protection scope of the present application. The above are only preferred implementations of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and variations can be made without departing from the technical principles of the present application, and these improvements and variations should also be regarded as the protection scope of the present application.

Claims

1. An evaporative cooling device, characterized in that: It comprises a heat exchanger (6), a wet curtain cooling device and a falling film spraying device (9), wherein the wet curtain cooling device is arranged on the windward side of the heat exchanger (6), and the falling film spraying device (9) is arranged above the heat exchanger (6); after the coolant enters the wet curtain cooling device for filtration, it enters the falling film spraying device (9) to cool the heat exchanger (6); A first liquid storage box (12) for collecting the cooling liquid of the wet curtain cooling device is arranged at the bottom of the wet curtain cooling device, and a second liquid storage box (13) for collecting the cooling liquid of the falling film spraying device (9) is arranged at the bottom of the falling film spraying device (9), the first liquid storage box (12) and the second liquid storage box (13) are spaced apart, the second liquid storage box (13) supplies liquid to the wet curtain cooling device, and the first liquid storage box (12) supplies liquid to the falling film spraying device (9).

2. The evaporative cooling device according to claim 1, characterized in that: The wet curtain cooling device comprises a wet curtain (7) and a wet curtain spraying device (8); the wet curtain spraying device (8) is arranged above the wet curtain (7) and supplies cooling liquid to the wet curtain (7).

3. The evaporative cooling device according to claim 2, characterized in that: The heat exchanger (6) comprises a subcooling section, the wet curtain (7) is arranged at the front side of the air inlet of the subcooling section, and the height of the wet curtain (7) is less than or equal to the height of the subcooling section.

4. The evaporative cooling device according to claim 3, characterized in that: The height of the wet curtain (7) is equal to the height of the supercooling section.

5. The evaporative cooling device according to claim 3, characterized in that: The heat exchanger (6) comprises a gas phase region (17), a gas-liquid two-phase region (18) and a liquid phase region (19), and the supercooling section is the liquid phase region (19).

6. The evaporative cooling device according to claim 1, characterized in that: The first liquid storage box (12) is connected to the falling film spraying device (9) via a first liquid supply pipeline, and a first pump (10) is provided on the first liquid supply pipeline.

7. The evaporative cooling device according to claim 1, characterized in that: The second liquid storage box (13) is connected to the wet curtain cooling device via a second liquid supply pipeline, and a second pump (11) is provided on the second liquid supply pipeline.

8. The evaporative cooling device according to claim 1, characterized in that: The second liquid storage box (13) is provided with a water replenishment pipeline.

9. The evaporative cooling device according to claim 8, characterized in that A control valve (16) is provided on the water supply pipeline.

10. An outdoor unit, comprising an evaporative cooling device, characterized in that: The evaporative cooling device is the evaporative cooling device according to any one of claims 1 to 9.

11. An air conditioning system, comprising an indoor unit (4), an outdoor unit (2), a compressor (1) and a throttling device (3), characterized in that: The outdoor unit (2) is the outdoor unit (2) according to claim 10, and the compressor (1), the outdoor unit (2), the throttling device (3) and the indoor unit (4) are arranged in sequence.

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