Pre-cooling device, control method and air cooling unit

Abstract

The application discloses a pre-cooling device, a control method and an air-cooled unit. The pre-cooling device is used for a condenser of the air-cooled unit and comprises a support provided with casters at the bottom and used for being arranged on a mounting base on which the condenser is mounted, a wet film arranged on the support, a spraying assembly arranged on the support and used for supplying water to the wet film, a temperature and humidity sensor arranged on the support, a variable frequency water pump arranged on the support and used for supplying water to the spraying assembly, and a driving device used for being arranged on the mounting base and used for driving the support to rotate relative to the mounting base, so that the support has an opening position and a closing position in use. When the support is rotated to the opening position, the wet film can be blocked on an air inlet surface of the condenser and can pre-cool air flowing to the air inlet surface of the condenser. When the support is rotated to the closing position, the blocking of the wet film on the air inlet surface of the condenser can be released. The pre-cooling device is favorable for reducing the spraying range and can adjust the spraying amount according to actual operation requirements of the air-cooled unit.

Description

Technical Field

[0001] This application relates to the field of air conditioning technology, and in particular to a pre-cooling device, control method and air-cooled unit. Background Technology

[0002] Traditional air-cooled chiller units experience a decline in condenser heat exchange efficiency after prolonged operation, leading to increased energy consumption and making them prone to high-pressure alarms during high-temperature summer operation. To address this issue, existing technology involves adding a misting system to the condenser's air inlet. Specifically, municipal water supply is atomized and sprayed onto the condenser's air inlet. The resulting water mist exchanges heat with the warmer air, thereby lowering the air inlet temperature and improving the condenser's heat exchange performance.

[0003] However, the above-mentioned solutions have a wide spray range for water mist, and the amount of water mist sprayed cannot be controlled. When too much water mist is sprayed, it will adhere to the heat exchange fins on the air inlet side of the condenser. After prolonged operation, scale will form on the heat exchange fins on the air inlet side of the condenser, reducing the air inlet channel and increasing the air inlet resistance. This, in turn, reduces the airflow to the air inlet side, ultimately affecting the heat exchange efficiency of the condenser. In addition, excessive water mist will spray onto the sheet metal casing of the air-cooled unit, the electrical box, and the ground, adversely affecting the service life of the air-cooled unit, electrical safety, and site hygiene. Summary of the Invention

[0004] This application aims to address at least one of the technical problems existing in the prior art. To this end, this application proposes a pre-cooling device that not only helps to reduce the spray range but also allows for adjustment of the spray volume according to the actual operating requirements of the air-cooled unit.

[0005] This application also proposes a control method for the aforementioned precooling device.

[0006] This application also proposes an air-cooled unit with the aforementioned pre-cooling device.

[0007] A pre-cooling device according to a first aspect embodiment of this application, for a condenser of an air-cooled unit, includes: a bracket for mounting the condenser on a mounting base, the bracket having casters at its bottom; a wet film disposed on the bracket; a spray assembly disposed on the bracket and above the wet film, the spray assembly supplying water to the wet film; a temperature and humidity sensor disposed on the bracket; and a variable frequency water pump disposed on the bracket, the variable frequency water pump having its inlet connected to a water source. The water outlet is connected to the water inlet of the spray assembly; a driving device is used to be mounted on the mounting base and to drive the bracket to rotate relative to the mounting base, so that the bracket has an open position and a closed position when in use. When the bracket is rotated to the open position, the wet film can block the air inlet surface of the condenser, so that the wet film can pre-cool the air flowing towards the air inlet surface of the condenser. When the bracket is rotated to the closed position, the wet film can release the obstruction of the air inlet surface of the condenser, so that the wet film can avoid the air flowing towards the air inlet surface of the condenser.

[0008] The pre-cooling device according to the embodiments of this application has at least the following beneficial effects: In use, the temperature and humidity sensor, the variable frequency water pump, and the drive device are electrically connected to the control device. The ambient temperature is obtained through the temperature and humidity sensor. When the ambient temperature is higher than a certain preset value, the control device controls the drive device to drive the bracket to the open position and turns on the variable frequency water pump to supply water to the spray assembly, so that the wet film pre-cools the air flowing to the air inlet surface of the condenser, thereby improving the heat exchange effect of the condenser. When the ambient temperature is lower than a certain preset value, the control device turns off the variable frequency water pump and controls the drive device to drive the bracket to the closed position. At this time, the pre-cooling device can avoid the air flowing to the air inlet surface of the condenser, thereby preventing the pre-cooling device from increasing the air inlet resistance of the air inlet surface of the condenser. In the above structure, a wet film supplied with water by the spray assembly is used to pre-cool the air flowing towards the air inlet of the condenser. Compared with the cooling method in the prior art that uses spray to directly spray onto the air inlet of the condenser, the spray assembly only needs to supply water to the wet film, which helps to reduce the spray range of the spray assembly. In addition, the control device can also adjust the operating frequency of the variable frequency water pump according to the actual operating requirements of the air-cooled unit. By adjusting the operating frequency of the variable frequency water pump, not only the spray volume of the spray assembly can be adjusted, but also the cooling intensity of the wet film during operation can be adjusted.

[0009] According to some embodiments of this application, the support is provided with a water tank with an open top, the water tank is located below the wet membrane, and the inlet end of the variable frequency water pump is connected to the water tank.

[0010] According to some embodiments of this application, the water tank is provided with a water inlet for connecting to an external water source.

[0011] According to some embodiments of this application, the bracket is provided with multiple baffles at intervals on the air outlet side corresponding to the wet film.

[0012] According to some embodiments of this application, a solar power panel is provided on the top of the bracket, and a storage battery electrically connected to the solar power panel is provided on the lower part of the bracket. The temperature and humidity sensor, the variable frequency water pump and the drive device are respectively electrically connected to the storage battery.

[0013] According to some embodiments of this application, the battery has a power interface for electrical connection with an external power source.

[0014] According to some embodiments of this application, the driving device includes a rotating shaft, a driving component, and a transmission assembly. The rotating shaft is fixedly mounted on the bracket, and the rotating shaft is vertically positioned and located on one side of the bracket along the horizontal direction. The lower end of the rotating shaft is rotatably connected to the mounting base. The driving component is fixedly mounted on the mounting base. The transmission assembly is disposed between the driving component and the rotating shaft so that the driving component can drive the rotating shaft to rotate relative to the mounting base.

[0015] According to some embodiments of this application, the driving component is an electric push rod, the transmission component is a gear and rack assembly, the gear and rack assembly includes a gear and a rack, the gear is coaxially disposed on the rotating shaft, and the rack is connected to the telescopic end of the electric push rod and meshes with the gear for transmission.

[0016] The control method according to a second aspect of this application, applied to a precooling device according to the first aspect of this application, includes the following steps:

[0017] Set the frequency ramp-up temperature T1, frequency ramp-down temperature T2, shutdown temperature T3, and startup temperature T4;

[0018] Obtain the condensing temperature T5 during the operation of the air-cooled unit;

[0019] Obtain the ambient temperature Ta;

[0020] When Ta > T4 and continues for a preset time, the control drive device drives the bracket to rotate to the open position, and then the variable frequency water pump is turned on to supply water to the wet film.

[0021] During the operation of the pre-cooling device, when T5 > T1, the frequency of the variable frequency water pump is increased. When the variable frequency water pump reaches the highest frequency, it is kept running at the highest frequency.

[0022] During the operation of the precooling device, when T2≤T5≤T1, the variable frequency water pump is controlled to maintain the current frequency.

[0023] During the operation of the precooling device, when T5 < T2, the frequency of the variable frequency water pump is reduced. When the frequency of the variable frequency water pump is reduced to the lowest frequency, it is kept running at the lowest frequency.

[0024] During the operation of the pre-cooling device, when Ta < T3 and continues for a preset time, the variable frequency water pump is turned off, and then the control drive device drives the bracket to rotate to the closed position.

[0025] An air-cooled unit according to a third aspect of this application includes a pre-cooling device according to the first aspect of this application described above.

[0026] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0027] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0028] Figure 1 This is a schematic diagram of the structure of the condenser and the precooling device in an air-cooled unit according to an embodiment of this application, where the air inlet surface of the condenser is provided with only one precooling device and the precooling device is turned on.

[0029] Figure 2 yes Figure 1 Enlarged view of a portion of point A in the middle;

[0030] Figure 3 yes Figure 2 Enlarged view of a portion of point B in the middle;

[0031] Figure 4 This is a top view of the condenser and precooling device in an air-cooled unit according to an embodiment of this application, where the air inlet surface of the condenser is provided with only one precooling device and the precooling device is closed;

[0032] Figure 5 This is a top view of the condenser and pre-cooling devices in an air-cooled unit according to an embodiment of this application, with two pre-cooling devices provided on the air inlet surface of the condenser and the pre-cooling devices closed.

[0033] Figure 6 This is a partial cross-sectional schematic diagram of a precooling device according to an embodiment of this application;

[0034] Figure 7 yes Figure 6 A schematic diagram of the drive device in the structure shown;

[0035] Figure 8 This is a partial cross-sectional schematic diagram of a precooling device according to an embodiment of this application from another perspective.

[0036] Figure label:

[0037] Condenser a, mounting base b, pre-cooling device 100, bracket 110, casters 111, baffle 112, wet film 120, spray assembly 130, temperature and humidity sensor 140, variable frequency water pump 150, drive device 160, rotating shaft 161, drive component 162, gear 163, rack 164, limit seat 165, bearing 166, water tank 170, water inlet 171, solar panel 180, battery 190, power interface 191. Detailed Implementation

[0038] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0039] In the description of this application, it should be understood that if directional descriptions are involved, such as up, down, front, back, left, right, etc., indicating the directional or positional relationship based on the directional or positional relationship shown in the accompanying drawings, it is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0040] In the description of this application, if words such as several, greater than, less than, exceeding, above, below, or within appear, "several" means one or more, "more than" means two or more, "greater than," "less than," "exceeding," etc. are understood to exclude the number itself, and "above," "below," "within," etc. are understood to include the number itself.

[0041] In the description of this application, the use of terms such as "first" and "second" is for the purpose of distinguishing technical features only, and should not be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated or the order of the technical features indicated.

[0042] In the description of this application, unless otherwise expressly defined, terms such as "setup," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this application in conjunction with the specific content of the technical solution.

[0043] Reference Figures 1 to 8According to an embodiment of this application, a pre-cooling device 100 is used for the condenser a of an air-cooled unit. The pre-cooling device 100 includes a support 110, a wet film 120, a spray assembly 130, a temperature and humidity sensor 140, a variable frequency water pump 150, and a drive device 160.

[0044] Specifically, bracket 110 is used to install on mounting base b for condenser a. Casters 111 are provided at the bottom of bracket 110. Wet film 120 is mounted on bracket 110. Spray assembly 130 is mounted on bracket 110 and located above wet film 120. Spray assembly 130 supplies water to wet film 120. Temperature and humidity sensor 140 is mounted on bracket 110. Variable frequency water pump 150 is mounted on bracket 110. The inlet of variable frequency water pump 150 is connected to a water source, and the outlet of variable frequency water pump 150 is connected to the inlet of spray assembly 130. Variable frequency water pump 150 is used for... Water is supplied to the spray assembly 130. The drive device 160 is installed on the mounting base b and is used to drive the bracket 110 to rotate relative to the mounting base b, so that the bracket 110 has an open position and a closed position when in use. When the bracket 110 is rotated to the open position, the wet film 120 can block the air inlet surface of the condenser a, so that the wet film 120 can pre-cool the air flowing to the air inlet surface of the condenser a. When the bracket 110 is rotated to the closed position, the wet film 120 can release the obstruction of the air inlet surface of the condenser a, so that the wet film 120 can avoid the air flowing to the air inlet surface of the condenser a.

[0045] In use, the temperature and humidity sensor 140, the variable frequency water pump 150, and the drive device 160 are electrically connected to the control device. The ambient temperature is obtained through the temperature and humidity sensor 140. When the ambient temperature is higher than a certain preset value, the control device controls the drive device 160 to drive the bracket 110 to the open position and turns on the variable frequency water pump 150 to supply water to the spray assembly 130, so that the wet film 120 pre-cools the air flowing towards the air inlet surface of the condenser a, thereby improving the heat exchange effect of the condenser a. When the ambient temperature is lower than a certain preset value, the control device turns off the variable frequency water pump 150 and controls the drive device 160 to drive the bracket 110 to the closed position. At this time, the pre-cooling device 100 can avoid the air flowing towards the air inlet surface of the condenser a, thereby preventing the pre-cooling device 100 from increasing the air inlet resistance of the air inlet surface of the condenser a. In the above structure, the wet film 120, supplied with water by the spray assembly 130, pre-cools the air flowing towards the air inlet surface of the condenser a. Compared with the cooling method in the prior art, which uses spray to directly spray onto the air inlet surface of the condenser a, the spray assembly 130 only needs to supply water to the wet film 120, which helps to reduce the spray range of the spray assembly 130. In addition, the control device can also adjust the operating frequency of the variable frequency water pump 150 according to the actual operating requirements of the air-cooled unit. By adjusting the operating frequency of the variable frequency water pump 150, not only the spray volume of the spray assembly 130 can be adjusted, but also the cooling intensity of the wet film 120 during operation can be adjusted.

[0046] It should be noted that in some embodiments, the aforementioned control device is an independent control device set in the precooling device 100, which enables the precooling device 100 to be quickly installed on-site for air-cooled units that have been put into use but have not installed the precooling device 100 (hereinafter referred to as "old air-cooled units") (without modifying the control device and related control program of the old air-cooled unit). That is, the precooling device 100 can be applied to the renovation project of the old air-cooled unit. During the renovation, the control device of the precooling device 100 only needs to communicate with the control device of the old air-cooled unit so that the control device of the precooling device 100 can obtain the operating data of the old air-cooled unit (such as the condensing temperature of the old air-cooled unit during operation).

[0047] It should be noted that in some other embodiments, the pre-cooling device 100 can also be controlled by the control device built into the air-cooled unit, that is, the air-cooled unit is equipped with the pre-cooling device 100 before it is put into use, which is not limited here.

[0048] It should be noted that in some of these embodiments, the caster 111 is a swivel wheel to facilitate the rotation of the bracket 110 relative to the mounting base b.

[0049] It should be noted that in some embodiments, the spray assembly 130 includes a horizontally arranged main pipeline and a plurality of nozzles spaced apart on the main pipeline. Of course, the nozzles can also be replaced with water outlets, which is not limited here.

[0050] It should be noted that in some embodiments, the installation base b is a concrete base. Of course, the installation base b can also be a plate-shaped metal component, which is not limited here.

[0051] Reference Figure 1 , Figure 6 and Figure 8 In some embodiments, a water tank 170 with an open top is provided on the support 110. The water tank 170 is located below the wet membrane 120. The water inlet of the variable frequency water pump 150 is connected to the water tank 170. The water tank 170 is used to store water as a water source for the variable frequency water pump 150. At the same time, the water tank 170 can collect water dripping from the bottom of the wet membrane 120, thereby realizing water recycling.

[0052] Reference Figure 8 In some embodiments, the water tank 170 is provided with a water inlet 171 for connecting to an external water source. When the water in the water tank 170 is insufficient, water can be added to the water tank 170 through the water inlet 171.

[0053] It should be noted that in some other embodiments, the inlet of the variable frequency water pump 150 can also be directly connected to an external water source (such as tap water). At the same time, a water receiving tray is set below the wet membrane 120 and connected to the sewer. In this case, the water tank 170 mentioned above is not required, and this is not a limitation.

[0054] Reference Figure 8 In some embodiments, multiple baffles 112 are spaced apart on the support 110 corresponding to the air outlet side of the wet film 120 (the side facing the air inlet surface of the condenser a). This helps prevent water sprayed by the spray assembly 130 onto the wet film 120 from splashing onto the heat exchange fins of the air inlet surface of the condenser a, thus reducing the risk of scale formation on the heat exchange fins of the air inlet surface of the condenser a. The multiple baffles 112 are spaced apart to allow airflow between adjacent baffles 112.

[0055] Reference Figure 1 , Figure 6 and Figure 8In some embodiments, a solar panel 180 is provided on the top of the bracket 110, and a battery 190 electrically connected to the solar panel 180 is provided on the lower part of the bracket 110. The temperature and humidity sensor 140, the variable frequency water pump 150 and the drive device 160 are electrically connected to the battery 190 respectively. The solar panel 180 supplies power to the temperature and humidity sensor 140, the variable frequency water pump 150 and the drive device 160, which helps to reduce energy consumption.

[0056] Reference Figure 1 , Figure 6 and Figure 8 In some embodiments, the battery 190 has a power interface 191 for electrical connection to an external power source. When the solar panel 180 fails or is unable to meet the power supply requirements due to insufficient sunlight, the battery 190 can be connected to an external power source through the power interface 191 to meet the power supply requirements.

[0057] Reference Figures 1 to 3 as well as Figures 6 to 7 In some embodiments, the drive device 160 includes a rotating shaft 161, a drive member 162, and a transmission assembly. The rotating shaft 161 is fixedly mounted on the bracket 110. The rotating shaft 161 is vertically positioned and located on one side of the bracket 110 along the horizontal direction. The lower end of the rotating shaft 161 is rotatably connected to the mounting base b. The drive member 162 is fixedly mounted on the mounting base b. The transmission assembly is disposed between the drive member 162 and the rotating shaft 161 so that the drive member 162 can drive the rotating shaft 161 to rotate relative to the mounting base b, thereby causing the bracket 110 to rotate relative to the mounting base b. Its structure is simple and easy to implement.

[0058] Reference Figure 2 , Figure 3 and Figure 7 In some embodiments, the drive element 162 is an electric push rod, and the transmission component is a gear and rack assembly. The gear and rack assembly includes a gear 163 and a rack 164. The gear 163 is coaxially mounted on the rotating shaft 161, and the rack 164 is connected to the telescopic end of the electric push rod and meshes with the gear 163 for transmission. Its structure is simple and easy to implement.

[0059] Reference Figure 2 , Figure 3 and Figure 7 In some embodiments, the drive device 160 further includes a limiting seat 165 for fixedly mounted on the mounting base b. The limiting seat 165 is provided with a limiting groove for supporting and guiding the rack 164, and the rack 164 is slidably embedded in the limiting groove. Of course, a guide groove can also be provided on the mounting base b corresponding to the rack 164. During installation, the rack 164 is slidably embedded in the guide groove. In this case, the limiting seat 165 is not required, and this is not a limitation.

[0060] Specifically, refer to Figure 3 and Figure 7 During installation, a mounting hole is provided on the mounting base b corresponding to the lower end of the rotating shaft 161, and the lower end of the rotating shaft 161 is rotatably inserted into the mounting hole. A bearing 166 is required between the lower end of the rotating shaft 161 and the mounting hole.

[0061] It should be noted that in some other embodiments, the rotating shaft 161 can also be driven to rotate relative to the mounting base b by a motor and a synchronous belt assembly, which is not limited here.

[0062] The control method according to an embodiment of this application, applied to the pre-cooling device 100 described above, includes the following steps:

[0063] Set the frequency ramp-up temperature T1, frequency ramp-down temperature T2, shutdown temperature T3, and startup temperature T4;

[0064] Obtain the condensing temperature T5 during the operation of the air-cooled unit (existing air-cooled units are equipped with relevant sensors for detection);

[0065] The ambient temperature Ta is obtained through the aforementioned temperature and humidity sensor 140;

[0066] When Ta > T4 and continues for a preset time, the control drive device 160 drives the bracket 110 to rotate to the open position, and then the variable frequency water pump 150 is turned on to supply water to the wet membrane 120.

[0067] During the operation of the pre-cooling device 100, when T5 > T1, it indicates that the heat exchange effect of condenser a is poor. At this time, the frequency of the variable frequency water pump 150 is increased to enhance the cooling intensity of the wet film 120, thereby improving the heat exchange effect of condenser a. When the frequency of the variable frequency water pump 150 reaches the highest frequency, it is kept running at the highest frequency.

[0068] During the operation of the pre-cooling device 100, when T2≤T5≤T1, it indicates that the heat exchange effect of condenser a is relatively ideal. At this time, the variable frequency water pump 150 can be controlled to maintain the current frequency.

[0069] During the operation of the pre-cooling device 100, when T5 < T2, it indicates that the heat exchange effect of condenser a has exceeded the actual operating requirements of the air-cooled unit. At this time, the frequency of the variable frequency water pump 150 is reduced to reduce the cooling intensity of the wet film 120, thereby reducing power consumption. When the frequency of the variable frequency water pump 150 is reduced to the lowest frequency, it is kept running at the lowest frequency.

[0070] During the operation of the pre-cooling device 100, when Ta < T3 and continues for a preset time, it indicates that the ambient temperature is low enough that there is no need to pre-cool the air flowing to the air inlet surface of the condenser a. At this time, the variable frequency water pump 150 is turned off, and then the drive device 160 is controlled to drive the bracket 110 to rotate to the closed position, thereby reducing the air inlet resistance of the air inlet surface of the condenser a.

[0071] An air-cooled unit according to an embodiment of this application includes the pre-cooling device 100 described above.

[0072] Reference Figure 1 and Figure 4 In some of these embodiments, the air inlet surface of condenser a is provided with only a pre-cooling device 100, similar to the single-door structure of a refrigerator.

[0073] Reference Figure 5 In some other embodiments, the air inlet surface of condenser a is provided with two pre-cooling devices 100, similar to the double-door structure of a refrigerator.

[0074] In the description of this specification, the use of terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," and "some examples" indicates that the specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0075] Although embodiments of this application have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the claims and their equivalents.

Claims

1. A precooling device, characterized in that, Condensers used in air-cooled units include: A bracket is provided for mounting on a foundation on which the condenser is installed, and casters are provided at the bottom of the bracket; A wet film, wherein the wet film is disposed on the support; A spray assembly is disposed on the support and located above the wet membrane, the spray assembly being used to supply water to the wet membrane; A temperature and humidity sensor, wherein the temperature and humidity sensor is mounted on the bracket; A variable frequency water pump is mounted on the bracket. The inlet of the variable frequency water pump is connected to a water source, and the outlet of the variable frequency water pump is connected to the inlet of the spray assembly. A driving device is provided, which is configured to be mounted on the mounting base and to drive the bracket to rotate relative to the mounting base, so that the bracket has an open position and a closed position during use. When the bracket is rotated to the open position, the wet film can block the air inlet surface of the condenser, so that the wet film can pre-cool the air flowing towards the air inlet surface of the condenser. When the bracket is rotated to the closed position, the wet film can release the obstruction of the air inlet surface of the condenser, so that the wet film can avoid the air flowing towards the air inlet surface of the condenser. The driving device includes a rotating shaft, a driving component, and a transmission assembly. The rotating shaft is fixedly mounted on the bracket, and is vertically positioned on one side of the bracket along the horizontal direction. The lower end of the rotating shaft is rotatably connected to the mounting base. The driving component is fixedly mounted on the mounting base. The transmission assembly is disposed between the driving component and the rotating shaft so that the driving component can drive the rotating shaft to rotate relative to the mounting base.

2. The precooling device as described in claim 1, characterized in that, The support frame is equipped with a water tank with an open top, which is located below the wet membrane. The inlet of the variable frequency water pump is connected to the water tank.

3. The precooling device as described in claim 2, characterized in that, The water tank is equipped with a water inlet for connecting to an external water source.

4. The precooling device as described in claim 1, characterized in that, The bracket is provided with multiple water baffles at intervals on the air outlet side corresponding to the wet film.

5. The precooling device as described in claim 1, characterized in that, A solar panel is installed at the top of the support frame, and a battery electrically connected to the solar panel is installed at the bottom of the support frame. The temperature and humidity sensor, the variable frequency water pump, and the drive device are respectively electrically connected to the battery.

6. The precooling device as described in claim 5, characterized in that, The battery has a power interface for electrical connection to an external power source.

7. The precooling device as described in claim 1, characterized in that, The driving component is an electric push rod, and the transmission component is a gear and rack assembly. The gear and rack assembly includes a gear and a rack. The gear is coaxially mounted on the rotating shaft, and the rack is connected to the telescopic end of the electric push rod and meshes with the gear for transmission.

8. A control method, characterized in that, The precooling device as described in any one of claims 1 to 7 comprises the following steps: Set the frequency ramp-up temperature T1, frequency ramp-down temperature T2, shutdown temperature T3, and startup temperature T4; Obtain the condensing temperature T5 during the operation of the air-cooled unit; Obtain the ambient temperature Ta; When Ta > T4 and continues for a preset time, the control drive device drives the bracket to rotate to the open position, and then the variable frequency water pump is turned on to supply water to the wet film. During the operation of the pre-cooling device, when T5 > T1, the frequency of the variable frequency water pump is increased. When the variable frequency water pump reaches the highest frequency, it is kept running at the highest frequency. During the operation of the precooling device, when T2≤T5≤T1, the variable frequency water pump is controlled to maintain the current frequency. During the operation of the precooling device, when T5 < T2, the frequency of the variable frequency water pump is reduced. When the frequency of the variable frequency water pump is reduced to the lowest frequency, it is kept running at the lowest frequency. During the operation of the pre-cooling device, when Ta < T3 and continues for a preset time, the variable frequency water pump is turned off, and then the control drive device drives the bracket to rotate to the closed position.

9. An air-cooled unit, characterized in that, Includes the precooling device as described in any one of claims 1 to 7.

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