Ultrasonic spray cooling device of air cooling system and control method

Abstract

The invention discloses an ultrasonic spray cooling device of an air cooling system, and relates to the technical field of power plant cooling equipment.The ultrasonic spray cooling device comprises a water feeding pump, a water pump inlet pipeline is installed on the left side of the water feeding pump, and uniform micro-mist with D32 smaller than or equal to 10 micrometers is generated by adopting a 1.7-2.4 MHz high-frequency transducer through the ultrasonic micro-mist technology; the micro fog is completely evaporated within 0.3-0.5 second, the heat absorption capacity is improved by 3 times, and the generated technical effect is that the evaporation efficiency is greater than or equal to 95%, and no visible water stain exists; the ultrasonic spraying device is mounted at an outlet of a fan (or an inlet of an air cooling system) through a fan mist conveying technology and is fully mixed with cooling air, so that uneven mixing of water mist and direct impact of liquid drops on a radiating tube bundle are avoided; through the intelligent control technology, on the basis of a multivariable coupling model of unit back pressure, steam flow entering an air cooling system, fan rotating speed, cooling air amount, cooling fin temperature, environment temperature, air humidity and wind power and wind direction, accurate control is achieved through an intelligent algorithm, and water is saved by 40% or above.

Description

Technical Field

[0001] This invention relates to the field of power plant cooling equipment technology, specifically to an ultrasonic spray cooling device and control method for an air-cooled system. Background Art

[0002] In my country, electricity supply relies on thermal power generation. Due to the unique resource advantages of some northern regions, the installed capacity of thermal power has continued to grow in recent years. In order to respond to the country's energy conservation and environmental protection policies, the application of air cooling systems (air-cooled islands) in thermal power plants is becoming more and more widespread.

[0003] A direct-cooling air-cooled island typically consists of components such as heat sinks, fans, heat pipes, and airflow ducts. The heat sinks dissipate heat, while the fans lower the device temperature through convection and heat absorption. The heat pipes and airflow ducts guide and disperse heat. When the device starts operating, the heat sink temperature gradually rises. At this point, the fans automatically start, drawing in fresh outside air and expelling it to lower the heat sink temperature. Simultaneously, the heat pipes and airflow ducts transfer heat to the heat sinks, and the heat is then dissipated into the surrounding air through fan convection.

[0004] Air-cooled islands utilize the principle of natural ventilation, lowering equipment temperature through convection and air exchange. When the ambient temperature is lower than the equipment temperature, natural ventilation removes the heat generated by the equipment, thus achieving a cooling effect.

[0005] As the operating years increase, changes in ambient temperature significantly impact the heat dissipation effect of air-cooled systems. During high-temperature operation in summer, the direct air-cooled system exhibits poor heat dissipation, leading to high back pressure and frequent load limiting, severely affecting the unit's economical operation. Therefore, it is essential to reduce unit back pressure, increase peak capacity, reduce coal consumption, and improve overall economic efficiency through cold-end treatment.

[0006] To achieve this goal, the patent discloses a spray cooling method for an air-cooled system, which utilizes the heat absorption of water evaporation to reduce the temperature of the air inlet of the air-cooled island. However, this method has many drawbacks, including high water consumption, easy erosion of the internal flow channels of the nozzle, insufficient droplet fineness (greater than 100μm), difficulty in accurately controlling the spray range, and excessive water consumption of the entire system. Therefore, this application proposes an ultrasonic spray cooling device and control method for an air-cooled system. Summary of the Invention

[0007] The technical problem solved by this invention is to overcome the defects of existing technologies, such as large droplet size, incomplete evaporation, and crude control, and to provide an ultrasonic spray cooling device and control method for an air-cooled system.

[0008] To achieve the above objectives, the present invention provides the following technical solution: an ultrasonic spray cooling device for an air-cooled system, comprising a water supply pump, an inlet pipe installed on the left side of the water supply pump, a control valve, a filter screen, and an inlet pressure gauge installed on the inlet pipe, the control valve, filter screen, and inlet pressure gauge being arranged from left to right; an outlet pipe installed on the right side of the water supply pump, an outlet pressure gauge, a check valve, an electric valve, a pressure transmitter, and a flow transmitter installed on the outlet pipe, the outlet pressure gauge, check valve, electric valve, pressure transmitter, and flow transmitter being arranged from left to right; and multiple ultrasonic spray devices installed on the outlet pipe.

[0009] Preferably, a water supply pipe is connected to one end of the water pump outlet pipe, and multiple ultrasonic spray devices are evenly installed on the water supply pipe.

[0010] Preferably, two main water supply pipes are connected to the water supply pipe, and multiple ultrasonic spray devices are respectively connected to the corresponding main water supply pipes.

[0011] Preferably, multiple unit chamber water supply headers are installed on the main water supply pipeline, and multiple unit chamber water supply branch pipes are installed on the unit chamber water supply headers. The unit chamber water supply branch pipes are connected to the corresponding ultrasonic spray devices.

[0012] Preferably, a shut-off valve is installed on the main water supply pipeline.

[0013] Preferably, an electric valve is also installed between the main water supply pipe and the water supply pipe.

[0014] Preferably, the ultrasonic spraying device is equipped with a fixed bracket.

[0015] A control method for an ultrasonic spray cooling device in an air-cooled system includes the following steps:

[0016] S1: First, collect data based on the unit back pressure, steam flow rate (which can be theoretically derived) entering the air conditioning system, fan speed, cooling air volume, radiator temperature, ambient temperature, air humidity, and air-cooled wind speed.

[0017] S2: If the collected data value is greater than expected, directly calculate the required atomization power and adjust the ultrasonic drive frequency between 1.7-2.4 MKz, and check again whether the RH is lower than 75%. If it is lower, continue to maintain it; if it is not lower, reduce the atomization power.

[0018] S3: If the collected data value is less than expected, directly determine whether the spray cooling equipment needs to be stopped. If it needs to be stopped, it will be stopped gradually. If it does not need to be stopped, it will enter a low-power standby state.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1. This invention utilizes ultrasonic micro-mist technology and employs a 1.7–2.4MHz high-frequency transducer to generate uniform micro-mist with a D32≤10μm. The micro-mist completely evaporates within 0.3–1 seconds, increasing heat absorption by 3 times. The resulting technical effect is an evaporation efficiency greater than or equal to 95%, with no visible water traces.

[0021] 2. This invention uses a fan-driven misting technology to install an ultrasonic spraying device at the fan outlet (or air-cooling system inlet) to fully mix with the cooling air, thus avoiding uneven mixing of fine water mist and direct impact of droplets on the heat dissipation tube bundle.

[0022] 3. This invention utilizes intelligent control technology, based on a multivariate coupled model of unit back pressure, steam flow rate (which can be theoretically derived) entering the air-cooling system, fan speed, cooling air volume, radiator temperature, ambient temperature, air humidity, and air speed of the air-cooling island, and employs intelligent algorithms to achieve precise control, saving more than 40% of water.

[0023] 4. This invention, through its modular design, allows for installation and maintenance without shutting down the system. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the system composition structure of the present invention;

[0025] Figure 2 This is an actual layout diagram of the equipment of the present invention;

[0026] Figure 3 For the present invention Figure 1 Side view in the middle;

[0027] Figure 4 This is the system control diagram of the present invention;

[0028] Figure 5 This is a flowchart of the control logic of the present invention;

[0029] Figure 6 This is a schematic diagram of the ultrasonic spray device of the present invention.

[0030] The following are the labels in the diagram: 1. Control valve; 2. Filter screen; 3. Inlet pressure gauge; 4. Water pump; 5. Outlet pressure gauge; 6. Check valve; 7. Electric valve; 8. Pressure transmitter; 9. Flow transmitter; 10. Ultrasonic spray device; 11. Main water supply pipeline; 12. Shut-off valve; 13. Water pump inlet pipeline; 14. Water pump outlet pipeline; 15. Water supply pipe; 16. Unit room water supply branch pipe; 17. Unit room water supply main pipe; 18. Fixed bracket. Detailed Implementation

[0031] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0032] Example 1

[0033] Please see Figure 1-6 This invention provides a technical solution: an ultrasonic spray cooling device for an air-cooled system, comprising a water pump 4, a water pump inlet pipe 13 installed on the left side of the water pump 4, a control valve 1, a filter screen 2 and an inlet pressure gauge 3 installed on the water pump inlet pipe 13, arranged from left to right; a water pump outlet pipe 14 installed on the right side of the water pump 4, an outlet pressure gauge 5, a check valve 6, an electric valve 7, a pressure transmitter 8 and a flow transmitter 9 installed on the water pump outlet pipe 14, arranged from left to right; and multiple ultrasonic spray devices 10 installed on the water pump outlet pipe 14.

[0034] In this embodiment, during use, the water pump inlet pipe 13 is connected to an external water source, and then the water supply pump 4 is driven to draw water from the source. The water source enters the ultrasonic spray device 10 through the water pump inlet pipe 13 and the water pump outlet pipe 14, and is finally sprayed out through the ultrasonic spray device 10 to achieve atomization and cooling.

[0035] When the water source flows, it is filtered by the filter screen 2 and controlled by the control valve 1, check valve 6 and electric valve 7. The operator can check the pressure through the inlet pressure gauge 3 and the outlet pressure gauge 5. Meanwhile, the pressure transmitter 8 converts the pressure parameters into a transmittable electrical signal for real-time monitoring and control of the industrial process. The flow transmitter 9 converts the flow parameters into an electrical signal to realize flow monitoring and regulation.

[0036] As an optional implementation, a water supply pipe 15 is connected to one end of the water pump outlet pipe 14, and multiple ultrasonic spray devices 10 are evenly installed on the water supply pipe 15.

[0037] In this embodiment, during use, the water supply pipe 15 is used to receive the water source, and then the water is distributed to the ultrasonic spray device 10 to achieve water supply.

[0038] As an optional implementation, two main water supply pipes 11 are connected to the water supply pipe 15, and multiple ultrasonic spray devices 10 are respectively connected to the corresponding main water supply pipes 11.

[0039] In this embodiment, during use, two main water supply pipes 11 are connected to the water supply pipe 15 to divert the water source and distribute the water to multiple ultrasonic spray devices 10 for subsequent spray cooling.

[0040] As an optional implementation, multiple unit chamber water supply headers 17 are inserted and installed on the main water supply pipe 11, and multiple unit chamber water supply branch pipes 16 are inserted and installed on the unit chamber water supply headers 17. The unit chamber water supply branch pipes 16 are connected to the corresponding ultrasonic spray devices 10.

[0041] In this embodiment, during use, water is diverted from the main water supply pipe 11 using the unit chamber water supply header 17 and the unit chamber water supply branch pipe 16, and directly supplied to the ultrasonic spray device 10 for subsequent spray cooling.

[0042] As an optional implementation, a shut-off valve 12 is installed on the main water supply pipeline 11.

[0043] In this embodiment, the use of the shut-off valve 12 can prevent water loss from the main water supply pipe 11 and ensure that all water is supplied to the ultrasonic spray device 10.

[0044] As an optional implementation, an electric valve 7 is also installed between the main water supply pipe 11 and the water supply pipe 15.

[0045] In this embodiment, during use, this setting can control the water flow between the main water supply pipe 11 and the water supply pipe 15.

[0046] As an optional implementation, a fixed bracket 18 is installed on the ultrasonic spray device 10.

[0047] In this embodiment, during use, the ultrasonic spray device 10 is stably installed by the fixed bracket 18, which further ensures the stable performance during subsequent operation.

[0048] A control method for an ultrasonic spray cooling device in an air-cooled system includes the following steps:

[0049] S1: First, collect data based on the unit back pressure, steam flow rate entering the air conditioning system (which can be theoretically derived), fan speed, cooling air volume, radiator temperature, ambient temperature, air humidity, and air-cooled island wind speed.

[0050] S2: If the collected data value is greater than expected, directly calculate the required atomization power and adjust the ultrasonic drive frequency between 1.7-2.4 MKz, and check again whether the RH is lower than 75%. If it is lower, continue to maintain it; if it is not lower, reduce the atomization power.

[0051] S3: If the collected data value is less than expected, directly determine whether the spray cooling equipment needs to be stopped. If it needs to be stopped, it will be stopped gradually. If it does not need to be stopped, it will enter a low-power standby state.

[0052] Example 2

[0053] like Figure 2 As shown: A water supply pipe 15 is arranged in the corridor, and a unit room water supply main pipe 17 is arranged in the fan room. Then, water is drawn from the unit room water supply main pipe 17 to supply water to the unit room water supply branch pipe 16. An ultrasonic spray device 10 is installed on the unit room water supply branch pipe 16. Each ultrasonic spray device 10 is equipped with an independent controllable solenoid valve, which can precisely control the opening and closing of each ultrasonic spray device 10.

[0054] In summary, the advantages of this invention are as follows: It innovatively uses an advanced ultrasonic spray device 10 to atomize water droplets (atomized particle size less than 10μm), replacing the high-pressure centrifugal pump with a common water pump 4. This maximizes the utilization of atomized water vapor, ensuring thorough mixing with cooling air to increase the vaporization area. During the full vaporization process, it maximizes the absorption of heat from the cooling air, reducing the dry-bulb temperature of the cooling air, improving the radiator's heat exchange efficiency, and reducing unit back pressure and coal consumption. The atomized water vapor has the longest residence time in the fan chamber, maximizing the filling of the entire fan chamber space and evenly distributing it in every corner of the radiator. It also boasts the highest demineralized water utilization rate and the lowest escape rate, reducing the risk of scaling and corrosion on the air-cooled radiator fins, greatly protecting the electrical equipment below the air-cooled island, and significantly saving on softened water usage.

[0055] Working Principle: Using a spray humidification method at the air inlet of the air cooler effectively reduces the temperature of the inlet air, thereby improving the cooling capacity of the air cooler. Water is atomized through nozzles to form droplets of a specific size. These droplets mix thoroughly with the air and evaporate rapidly during their movement. Due to the high latent heat of vaporization of water, its evaporation absorbs a large amount of heat from the air, thus lowering the air temperature. The cooled, humidified air is then delivered to the air cooler radiator to enhance its heat exchange effect. A small amount of unvaporized droplets flow over the high-temperature radiator fins under the influence of wind. At this high temperature, the droplets vaporize rapidly, absorbing heat from the radiator and the surrounding air. Under certain atomization intensity and spray angle, the spray also forms a water film on the surface of the radiator fins. The evaporation of this water film further removes heat, improving the air cooler's heat exchange capacity and thus increasing the unit's output.

[0056] During atomization, the dispersion of water is achieved by an ultrasonic spray device. The strength of heat and mass exchange between air and fine water droplets in the atomization cooling system, the energy consumption of the ultrasonic spray device, and the ease of maintenance are all directly related to the performance of the ultrasonic spray device. Therefore, the ultrasonic spray device is the core component of water atomization, and the quality of atomization directly affects the heat and moisture exchange effect of spray humidification. In addition, the development of an intelligent control system is crucial. Through a multivariate coupling model of unit back pressure, steam flow rate entering the air-cooling system, fan speed, cooling air volume, heat sink temperature, ambient temperature, air humidity, wind force and direction, precise control is achieved, resulting in water saving and energy reduction.

[0057] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. An ultrasonic spray cooling device for an air-cooled system, comprising a water pump (4), characterized in that: The water pump (4) has a water pump inlet pipe (13) installed on its left side. The water pump inlet pipe (13) is equipped with a control valve (1), a filter screen (2) and an inlet pressure gauge (3). The control valve (1), the filter screen (2) and the inlet pressure gauge (3) are arranged from left to right. The water pump (4) has a water pump outlet pipe (14) installed on its right side. The water pump outlet pipe (14) is equipped with an outlet pressure gauge (5), a check valve (6), an electric valve (7), a pressure transmitter (8) and a flow transmitter (9). The outlet pressure gauge (5), the check valve (6), the electric valve (7), the pressure transmitter (8) and the flow transmitter (9) are arranged from left to right. The water pump outlet pipe (14) is equipped with multiple ultrasonic spray devices (10).

2. The ultrasonic spray cooling device for an air-cooled system according to claim 1, characterized in that: One end of the water pump outlet pipe (14) is connected to a water supply pipe (15), and multiple ultrasonic spray devices (10) are evenly installed on the water supply pipe (15).

3. The ultrasonic spray cooling device for an air-cooled system according to claim 2, characterized in that: Two main water supply pipes (11) are connected to the water supply pipe (15), and multiple ultrasonic spray devices (10) are connected to the corresponding main water supply pipes (11).

4. The ultrasonic spray cooling device for an air-cooled system according to claim 3, characterized in that: Multiple unit chamber water supply headers (17) are inserted and installed on the main water supply pipe (11), and multiple unit chamber water supply branch pipes (16) are inserted and installed on the unit chamber water supply headers (17). The unit chamber water supply branch pipes (16) are connected to the corresponding ultrasonic spray devices (10).

5. The ultrasonic spray cooling device for an air-cooled system according to claim 3, characterized in that: A shut-off valve (12) is installed on the main water supply pipeline (11).

6. The ultrasonic spray cooling device for an air-cooled system according to claim 3, characterized in that: An electric valve (7) is also installed between the main water supply pipe (11) and the water supply pipe (15).

7. The ultrasonic spray cooling device for an air-cooled system according to claim 1, characterized in that: The ultrasonic spray device (10) is equipped with a fixed bracket (18).

8. A control method for an ultrasonic spray cooling device in an air-cooled system, characterized in that: The following steps are involved: S1: First, collect data based on the unit back pressure, the steam flow rate entering the air-cooling system (calculated according to the unit design conditions or extrapolated from the theory), the fan speed, the cooling air volume, the heat sink temperature, the ambient temperature, the air humidity, and the air speed of the air-cooling island. S2: If the collected data value is greater than expected, directly calculate the required atomization power and adjust the ultrasonic drive frequency between 1.7-2.4 MKz, and check again whether the RH is lower than 75%. If it is lower, continue to maintain it; if it is not lower, reduce the atomization power. S3: If the collected data value is less than expected, directly determine whether the spray cooling equipment needs to be stopped. If it needs to be stopped, it will be stopped gradually. If it does not need to be stopped, it will enter a low-power standby state.

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