Longwall coal mining face internal and external cooperative cooling system

Abstract

The application relates to the technical field of coal mine production, and provides a longwall coal mining face internal-external collaborative cooling and temperature reducing system. In the system, chilled water of a refrigeration station is connected with air inlet cooling and temperature reducing units and air return cooling and temperature reducing units arranged in air inlet and air return gateways through two parallel branches, the chilled water is provided to the air inlet cooling and temperature reducing units and the air return cooling and temperature reducing units to form independent cooling cycles, the air inlet cooling and temperature reducing units and the air return cooling and temperature reducing units perform internal-external synchronous and collaborative cooling on coal mining equipment and environmental air flow of the coal mining face, heat generation at the coal mining face is reduced, the working environment temperature is reduced, the working environment of a heat-harm mine is effectively improved in multiple dimensions, the coal mining production efficiency is improved, and physical and mental damage of workers caused by heat harm is reduced.

Description

Technical Field

[0001] This application relates to the field of coal mine production technology, and in particular to a coordinated cooling system for both inside and outside longwall coal mining faces. Background Technology

[0002] As shallow coal resources are depleted, coal mining has entered a deeper stage, leading to a sharp increase in the geothermal gradient—the temperature of conventional strata rises by 100 meters per second. Deep mining areas are affected by geology and lithology, rising to [a certain level]. The geothermal anomaly zone is even higher. The resulting destructive underground thermal environment exerts systemic constraints on mining operations, affecting personnel, equipment processes, and safety control.

[0003] At the personnel level, temperatures at deep working faces generally exceed [a certain threshold]. Some mines without refrigeration equipment have reached , superimposed High humidity hinders the evaporation of sweat from the human body, which can lead to heatstroke in mild cases and organ failure in severe cases. Long-term exposure can also induce rheumatism, skin diseases, and cardiovascular diseases, with irreversible damage. Meanwhile, every increase in temperature... Decreased labor efficiency of workers Attention and reaction speed decrease significantly; when the temperature exceeds The physical endurance time for personnel has been reduced from 8 hours to Small mistakes can create hidden dangers.

[0004] At the equipment and process level, high temperatures accelerate the aging and failure of electromechanical equipment, reduce the viscosity of hydraulic support emulsions, damage the insulation layers of electrical equipment, and double the equipment failure rate compared to normal temperature environments. High temperatures also accelerate coal oxidation, inducing spontaneous combustion, and the coupling of underground hot water with high-temperature rock masses can corrode equipment. Furthermore, high temperatures alter the physical and mechanical properties of the coal seam and surrounding rock, leading to surrounding rock deformation and support structure failure. Simultaneously, they reduce mine ventilation efficiency, creating localized heat accumulation, forcing frequent adjustments to mining processes, and leading some mines to adopt intermittent production modes, resulting in reduced annual output. .

[0005] In terms of safety control, temperature changes have the most severe impact. When the temperature at the work site exceeds... The accident rate is up to 1.5 times higher than at normal temperature, and the rate increases with each increase in temperature. The incidence of workplace accidents has increased. The combination of human error and equipment malfunction can easily lead to direct accidents such as chute blockage and equipment collisions. More dangerously, high temperatures can cause adsorbed gases to escape, reduce the stability of the surrounding rock, and catalyze disasters such as gas outbursts and rock bursts. At the same time, it lowers the explosion threshold of dust and flammable gases, significantly increasing the risk of explosion. Moreover, such disasters spread faster and are more destructive in high-temperature confined spaces, forming a safety risk chain and becoming a core problem restricting the safe and efficient development of deep coal mines. Summary of the Invention

[0006] The purpose of this application is to provide a coordinated cooling system for both inside and outside longwall coal mining faces to solve or alleviate the problems existing in the prior art.

[0007] To achieve the above objectives, this application provides the following technical solution: This application provides a coordinated cooling system for both inside and outside a longwall coal mining face, including: a refrigeration station, an intake air cooling unit, and a return air cooling unit; The refrigeration station forms an independent cooling cycle with the intake air cooling unit and the return air cooling unit, and performs synchronous and coordinated cooling of the coal mining equipment and the ambient airflow in the coal mining face. The intake air cooling unit and the return air cooling unit are respectively arranged in the intake roadway and the return air roadway.

[0008] Preferably, the air intake cooling unit includes an air cooler and an air intake heat exchanger that share the same inlet water pipe and the same outlet water pipe and are connected to the refrigeration station. The return air cooling unit includes: water-cooled fins and a return air heat exchanger that share the same inlet and outlet water pipes and are connected to the refrigeration station. Among them, the air cooler cools the ambient airflow entering the coal mining face by using chilled water input from the refrigeration station; the air inlet heat exchanger cools the input cooling medium by using chilled water input from the refrigeration station, and then delivers the cooled cooling medium to the coal cutter sprayer at the coal mining face. The water-cooled plates cool the ambient airflow at the hydraulic support in the coal mining face using chilled water input from the refrigeration station; the return air heat exchanger cools the supplied emulsion on the emulsion supply side of the hydraulic support using chilled water input from the refrigeration station.

[0009] Preferably, according to the constructed refrigeration model: Determine the cooling capacity of the air cooler The difference between the heat of inlet water and the heat of return water of the water-cooled plate. ; In the formula, The surface heat transfer coefficient between the surrounding rock and the airflow at the working face. These refer to the width and height of the coal mining face, respectively. This refers to the distance from the air intake of the coal mining face to the water-cooled fins. This refers to the distance from the return air inlet of the coal mining face to the water-cooled fins. The average surface temperature of the surrounding rock at the coal mining face. The airflow temperature after heat exchange in the air cooler The airflow temperature at the return air roadway port; The heat transfer coefficient of the water-cooled plate is... This represents the total heat transfer area of ​​the water-cooled plate. The temperature at which the airflow reaches the water-cooled plate; The return water temperature of the water-cooled plate. To supply temperature for the chilled water in the refrigeration station.

[0010] Preferably, according to the formula: Determine the temperature at which the airflow reaches the water-cooled fins. In the formula, The average surface temperature of the surrounding rock at the coal mining face. The airflow temperature after heat exchange in the air cooler This refers to the distance from the air intake of the coal mining face to the water-cooled fins. The surface heat transfer coefficient between the surrounding rock and the airflow at the working face. These refer to the width and height of the coal mining face, respectively. The air supply volume for the coal mining face. The density of the airflow at the coal mining face. This is the specific heat capacity of air.

[0011] Preferably, according to the formula: Sure Let be the heat transfer coefficient of the water-cooled fin pipe; where, The convective heat transfer coefficient between the inner wall of the water-cooled fin tube and the water inside the water-cooled fin tube is given. The convective heat transfer coefficient between the outer wall of the water-cooled fin pipe and the ambient airflow. The inner diameter of the water-cooled fin's pipe. The thermal conductivity of the pipe wall of the water-cooled fin is given. This refers to the outer diameter of the pipe used for the water-cooled plate.

[0012] Preferably, the distance from the air inlet of the coal mining face to the water cooling plate is determined based on the number of water cooling plates and the width of the hydraulic support.

[0013] Preferably, according to the constructed inlet-side flow rate model: Determine the chilled water supply for the air cooler chilled water supply to the air intake heat exchanger ; In the formula, For the cooling capacity of the air cooler, For the specific heat capacity of water, The specific gravity of water, This refers to the return water temperature of the air cooler. The supply of cooling medium to the intake air heat exchanger. The supply temperature of the cooling medium. The temperature of the cooling medium after cooling is reached. The chilled water return temperature of the air inlet heat exchanger; To supply temperature for the chilled water in the refrigeration station.

[0014] Preferably, according to the constructed return air side flow model: Determine the chilled water supply for the water-cooled plates. Chilled water supply to the return air heat exchanger ; In the formula, This is the difference between the heat of inlet water and the heat of return water for the water-cooled plate; For the specific heat capacity of water, The specific gravity of water, The return water temperature of the water-cooled plate. The emulsion supply for the hydraulic support flowing through the return air heat exchanger. The specific heat capacity of the emulsion. To supply temperature to the emulsion of the hydraulic support. The emulsion outlet temperature of the hydraulic support. The return water temperature of the chilled water in the return air heat exchanger; To supply temperature for the chilled water in the refrigeration station.

[0015] Preferably, there are multiple water-cooled plates, which are arranged at intervals along the width of the coal mining face and connected in series.

[0016] Preferably, the refrigeration station forms an independent cooling cycle with the intake air cooling unit and the return air cooling unit through two parallel branches; or, The intake air cooling unit and the return air cooling unit form independent cooling cycles with the independent refrigeration stations set on the intake side and return air side, respectively.

[0017] Beneficial effects: In the longwall coal mining face internal and external coordinated cooling system provided in this application embodiment, the refrigeration station forms an independent cooling cycle with the intake air cooling unit and the return air cooling unit, respectively, to synchronously and coordinatedly cool the coal mining equipment and environmental airflow in the coal mining face; wherein, the intake air cooling unit and the return air cooling unit are respectively arranged in the intake roadway and the return air roadway.

[0018] In this way, the chilled water of the refrigeration station is connected to the intake air cooling unit and the return air cooling unit arranged in the intake air roadway and the return air roadway respectively through two parallel branches. The chilled water is supplied to the intake air cooling unit and the return air cooling unit to form an independent cooling cycle. The intake air cooling unit and the return air cooling unit perform synchronous and coordinated cooling of the coal mining equipment and the ambient airflow at the coal mining face, reducing the heat generation at the coal mining face and lowering the working environment temperature. This effectively improves the working environment of the heat-hazardous mine from multiple dimensions, increases coal mining production efficiency, and reduces the physical and mental harm of heat hazards to the workers. Attached Figure Description

[0019] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. Wherein: Figure 1 This is a schematic diagram of a combined internal and external cooling system for a longwall coal mining face, provided according to some embodiments of this application. Figure 2 This is a schematic diagram illustrating the principle of a coordinated cooling system for the inside and outside of a longwall coal mining face, according to some embodiments of this application. Detailed Implementation

[0020] The present application will now be described in detail with reference to the accompanying drawings and embodiments. Various examples are provided by way of explanation and not by way of limitation. In fact, those skilled in the art will understand that modifications and variations can be made to the present application without departing from the scope or spirit of the present application. For example, a feature shown or described as part of one embodiment may be used in another embodiment to produce yet another embodiment. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention should fall within the scope of protection of the embodiments of the present invention.

[0021] There are many heat sources in a coal mining face, the most important being the heat dissipation from the surface of the coal and rock mass, which exchanges heat with the airflow and exacerbates the rise in air temperature. Inside the coal mining face, the coal cutter generates a large amount of coal dust during operation. Currently, only dust suppression spraying is used, neglecting the fact that the loose coal material cut off will release a large amount of heat, causing the air temperature to rise. The spraying water comes from the ambient temperature water supply underground and has no cooling effect.

[0022] In addition, the emulsion used for lifting and lowering the hydraulic supports inside the coal mining face will increase in temperature during the pressurization process. Since the hydraulic supports cover the entire coal mining face, this will undoubtedly increase the airflow temperature of the coal mining face, worsen the temperature environment of the coal mining face, and be detrimental to the progress of coal mining work.

[0023] Currently, commonly used underground cooling systems primarily employ single air coolers to cool the airflow temperature. However, a single air cooler is insufficient to meet the demands of longwall mining faces, often necessitating the installation of multiple air coolers in the roadway, significantly increasing costs. Furthermore, the airflow temperature rises after heat exchange with the coal and rock mass in the front half of the mining face, resulting in minimal or no cooling in the rear half, making it difficult to maintain a consistent working environment temperature across the entire mining face. In addition, the chilled water supplied by the cooling station is not utilized efficiently, merely exchanging heat with the air coolers before being returned, leading to low utilization efficiency.

[0024] To address the aforementioned issues, this embodiment provides a coordinated cooling system for longwall coal mining faces. Through an intake air cooling unit and a return air cooling unit connected to a refrigeration station, chilled water provided by the refrigeration station is used to simultaneously and synergistically cool the external airflow, the internal coal cutter spray water, the internal hydraulic support emulsion, and the airflow in the latter half of the mining face. This reduces heat generation at the mining face while lowering the ambient temperature, effectively improving the working environment in heat-prone mines from multiple dimensions, increasing coal mining efficiency, and reducing the physical and mental harm of heat hazards to workers.

[0025] like Figure 1 , Figure 2 As shown, in this system, pipelines are arranged in the intake and return air roadways of the coal mining face to connect with the refrigeration station, introducing chilled water from the refrigeration station. Simultaneously, the introduced chilled water is connected to the intake air cooling unit and the return air cooling unit through two parallel branches (pipelines) respectively located in the intake and return air roadways. The intake air cooling unit and the return air cooling unit each form an independent cooling circulation path with the refrigeration station, achieving synchronous and coordinated cooling of the coal mining equipment (coal cutter, hydraulic supports, etc.) and the ambient airflow at the coal mining face. Alternatively, the intake air cooling unit and the return air cooling unit can be connected to the same refrigeration station through two parallel branches and form independent cooling circulations, or they can form independent cooling circulations with independent refrigeration stations located on the intake and return air sides respectively.

[0026] The air-cooled unit includes an air cooler and an air-cooled heat exchanger. The air cooler and the air-cooled heat exchanger are arranged side by side on the air-cooling side, sharing the same inlet water pipe and the same outlet water pipe connected to the refrigeration station. In other words, the chilled water introduced from the refrigeration station to the air-cooling side is divided into two parallel paths and flows into the air cooler and the air-cooled heat exchanger. At the same time, the outlet water of the air cooler and the air-cooled heat exchanger shares a single pipe to return to the refrigeration station.

[0027] The return air cooling unit includes water-cooled fins and a return air heat exchanger. The water-cooled fins and the return air heat exchanger are arranged side by side on the return air side, sharing the same inlet and outlet water pipes connected to the refrigeration station. In other words, the chilled water introduced from the refrigeration station to the return air side is divided into two parallel paths and flows into the water-cooled fins and the return air heat exchanger. At the same time, the outlet water from the water-cooled fins and the return air heat exchanger shares a single pipe that returns to the refrigeration station.

[0028] In this embodiment, the air cooler cools the ambient airflow entering the coal mining face by using chilled water input from the refrigeration station; the water-cooled plate cools the ambient airflow at the hydraulic support in the coal mining face by using chilled water input from the refrigeration station.

[0029] The refrigeration model constructed includes: Determine the cooling capacity of the air cooler The difference between the heat of inlet water and the heat of return water of the water-cooled plate. In the formula, The surface heat transfer coefficient between the surrounding rock and the airflow at the working face. These refer to the width and height of the coal mining face, respectively. This refers to the distance from the air intake of the coal mining face to the water-cooled fins. This refers to the distance from the return air inlet of the coal mining face to the water-cooled fins. In a specific example, the distance from the air inlet of the coal mining face to the water-cooled fins is determined by the number of water-cooled fins and the width of the hydraulic supports. That is, the distance from the return air inlet of the coal mining face to the water-cooled fins. , This represents the total number of water-cooled plates. The width of a single hydraulic support.

[0030] The average surface temperature of the surrounding rock at the coal mining face. The airflow temperature after heat exchange in the air cooler The airflow temperature at the return air roadway port; The heat transfer coefficient of the water-cooled fin pipe is given. The total heat transfer area of ​​the water-cooled fins is given by the formula: Sure, This represents the heat transfer area of ​​a single water-cooled fin.

[0031] The temperature at which the airflow reaches the water-cooled plate; The return water temperature of the water-cooled plate. The chilled water supply temperature is provided to the refrigeration station; the water-cooled plates are included in the return air cooling unit, and the chilled water input from the refrigeration station cools the ambient airflow at the hydraulic support in the coal mining face.

[0032] In a specific example, according to the formula: Determine the temperature at which the airflow reaches the water-cooled fins. In the formula, The average surface temperature of the surrounding rock at the coal mining face. The airflow temperature after heat exchange in the air cooler This refers to the distance from the air intake of the coal mining face to the water-cooled fins. The surface heat transfer coefficient between the surrounding rock and the airflow at the working face. These refer to the width and height of the coal mining face, respectively. The air supply volume for the coal mining face. The density of the airflow at the coal mining face. This is the specific heat capacity of air.

[0033] According to the formula: Sure Let be the heat transfer coefficient of the water-cooled fin pipe; where, The convective heat transfer coefficient between the inner wall of the water-cooled fin tube and the water inside the water-cooled fin tube is given. The convective heat transfer coefficient between the outer wall of the water-cooled fin pipe and the ambient airflow. The inner diameter of the water-cooled fin's pipe. The thermal conductivity of the pipe wall of the water-cooled fin is given. This refers to the outer diameter of the pipe used for the water-cooled plate.

[0034] In a specific example, multiple water-cooled radiators are arranged at intervals and connected in series along the width of the coal face. Specifically, the water-cooled radiators are shell-and-tube type radiators. Multiple water-cooled radiators are spaced apart on the hydraulic supports in the rear half of the coal face. The radiators are connected by flexible pipes. The inlet of the first water-cooled radiator is connected to the chilled water introduced from the return air side, and the outlet of the last water-cooled radiator is connected to the return water pipeline of the chilled water on the return air side via a connecting pipe. The chilled water flowing through the water-cooled radiators exchanges heat with the ambient airflow through the surface of the radiators, reducing the air temperature in the rear half of the coal face.

[0035] In a specific application scenario, the air intake heat exchanger has two inlets and two outlets. The two inlets are connected to chilled water and cooling medium (underground ambient temperature water), respectively, while the two outlets are connected to the chilled water return pipeline and the coal cutter sprayer, respectively. The chilled water and cooling medium (underground ambient temperature water) exchange heat inside the air intake heat exchanger, causing the cooling medium to cool down before being supplied to the coal cutter sprayer, thus achieving simultaneous coal cutting and cooling / dust reduction inside the coal face. The chilled water, after heat exchange, has a higher temperature and flows back to the refrigeration station through the chilled water return pipeline.

[0036] Furthermore, according to the constructed inlet-side flow rate model: Determine the chilled water supply for the air cooler chilled water supply to the air intake heat exchanger In this way, the chilled water supply of the air cooler was determined. chilled water supply to the air intake heat exchanger Then, at the chilled water inlet pipe on the air inlet side, the chilled water flow rate entering the air cooler and air inlet heat exchanger is distributed according to the corresponding flow rate ratio through the flow ratio valve.

[0037] In the inlet-side flow model, For the cooling capacity of the air cooler, For the specific heat capacity of water, The specific gravity of water, This refers to the return water temperature of the air cooler. The supply of cooling medium to the intake air heat exchanger. The supply temperature of the cooling medium. The temperature of the cooling medium after cooling is reached. The chilled water return temperature of the air inlet heat exchanger; To supply temperature for the chilled water in the refrigeration station.

[0038] In another specific application scenario, the return air heat exchanger has two inlets and two outlets. The two inlets are connected to the chilled water and emulsion pump introduced from the return air side, respectively. The two outlets are connected to the chilled water return pipeline on the return air side and the emulsion supply pipeline for the hydraulic support, respectively. Inside the return air heat exchanger, the high-temperature emulsion flowing in from the emulsion pump outlet exchanges heat with the chilled water to become a ground-temperature emulsion. This low-temperature emulsion is supplied to the hydraulic support inside the coal face to reduce heat generation within the coal face. The chilled water in the return air heat exchanger heats up after the heat exchange and flows back to the chilled water return pipeline on the return air side.

[0039] Furthermore, according to the constructed return air side flow model: Determine the chilled water supply for the water-cooled plates. Chilled water supply to the return air heat exchanger In this way, the chilled water supply of the water-cooled plates was determined. Chilled water supply to the return air heat exchanger Then, at the chilled water inlet pipe on the return air side, the chilled water flow rate entering the water-cooled fins and return air heat exchanger is distributed according to the corresponding flow rate ratio through a flow ratio valve.

[0040] In the return air flow model This is the difference between the heat of inlet water and the heat of return water for the water-cooled plate; For the specific heat capacity of water, The specific gravity of water, The return water temperature of the water-cooled plate. The emulsion supply for the hydraulic support flowing through the return air heat exchanger. The specific heat capacity of the emulsion. To supply temperature to the emulsion of the hydraulic support. The emulsion outlet temperature of the hydraulic support. To supply temperature for the chilled water in the refrigeration station.

[0041] In a specific example, the chilled water inlet and return pipes are wrapped with polyurethane to effectively reduce cold loss; the air cooler, air inlet heat exchanger, and return air heat exchanger on the air inlet side are respectively located at a distance of no more than [missing information] from the coal face inlet. This is to reduce the cold loss of cold air entering the coal mining face, and at the same time effectively avoid the impact on the longwall mining face.

[0042] In this way, the chilled water from the refrigeration station is used to cool the external airflow, the internal coal cutter spray water, the internal hydraulic support emulsion, and the airflow in the latter half of the coal face. This allows for coordinated cooling inside and outside the coal face, which not only improves the overall utilization efficiency of the cooling water in the refrigeration station but also effectively improves the thermal environment of the coal face, thereby increasing coal mining production efficiency and reducing the harm of heat to the human body.

[0043] In the description of this invention, it should be understood that the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0044] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A coordinated internal and external cooling system for longwall coal mining faces, characterized in that, include: Refrigeration station, air intake cooling unit and return air cooling unit; The refrigeration station forms an independent cooling cycle with the intake air cooling unit and the return air cooling unit, and performs synchronous and coordinated cooling of the coal mining equipment and the ambient airflow in the coal mining face. The intake air cooling unit and the return air cooling unit are respectively arranged in the intake roadway and the return air roadway.

2. The system according to claim 1, characterized in that, The air intake cooling unit includes an air cooler and an air intake heat exchanger that share the same inlet water pipe and the same outlet water pipe and are connected to the refrigeration station. The return air cooling unit includes: water-cooled fins and a return air heat exchanger that share the same inlet and outlet water pipes and are connected to the refrigeration station. Among them, the air cooler cools the ambient airflow entering the coal mining face by using chilled water input from the refrigeration station; the air inlet heat exchanger cools the input cooling medium by using chilled water input from the refrigeration station, and then delivers the cooled cooling medium to the coal cutter sprayer at the coal mining face. The water-cooled plates cool the ambient airflow at the hydraulic support in the coal mining face using chilled water input from the refrigeration station; the return air heat exchanger cools the supplied emulsion on the emulsion supply side of the hydraulic support using chilled water input from the refrigeration station.

3. The system according to claim 2, characterized in that, According to the constructed refrigeration model: Determine the cooling capacity of the air cooler The difference between the heat of inlet water and the heat of return water of the water-cooled plate. ; In the formula, The surface heat transfer coefficient between the surrounding rock and the airflow at the working face. These refer to the width and height of the coal mining face, respectively. This refers to the distance from the air intake of the coal mining face to the water-cooled fins. This refers to the distance from the return air inlet of the coal mining face to the water-cooled fins. The average surface temperature of the surrounding rock at the coal mining face. The airflow temperature after heat exchange in the air cooler The airflow temperature at the return air roadway port; The heat transfer coefficient of the water-cooled plate is... This represents the total heat transfer area of ​​the water-cooled plate. The temperature at which the airflow reaches the water-cooled plate; The return water temperature of the water-cooled plate. To supply temperature for the chilled water in the refrigeration station.

4. The system according to claim 3, characterized in that, According to the formula: Determine the temperature at which the airflow reaches the water-cooled fins. In the formula, The average surface temperature of the surrounding rock at the coal mining face. The airflow temperature after heat exchange in the air cooler This refers to the distance from the air intake of the coal mining face to the water-cooled fins. The surface heat transfer coefficient between the surrounding rock and the airflow at the working face. These refer to the width and height of the coal mining face, respectively. The air supply volume for the coal mining face. The density of the airflow at the coal mining face. This is the specific heat capacity of air.

5. The system according to claim 3, characterized in that, According to the formula: Sure Let be the heat transfer coefficient of the water-cooled fin pipe; where, The convective heat transfer coefficient between the inner wall of the water-cooled fin tube and the water inside the water-cooled fin tube is given. The convective heat transfer coefficient between the outer wall of the water-cooled fin pipe and the ambient airflow. The inner diameter of the water-cooled fin's pipe. The thermal conductivity of the pipe wall of the water-cooled fin is given. This refers to the outer diameter of the pipe used for the water-cooled plate.

6. The system according to claim 3, characterized in that, The distance from the air inlet to the water-cooled plates in the coal mining face is determined based on the number of water-cooled plates and the width of the hydraulic support.

7. The system according to claim 2, characterized in that, According to the constructed inlet-side flow rate model: Determine the chilled water supply for the air cooler chilled water supply to the air intake heat exchanger ; In the formula, For the cooling capacity of the air cooler, For the specific heat capacity of water, The specific gravity of water, This refers to the return water temperature of the air cooler. The supply of cooling medium to the intake air heat exchanger. The supply temperature of the cooling medium. The temperature of the cooling medium after cooling is reached. The chilled water return temperature of the air inlet heat exchanger; To supply temperature for the chilled water in the refrigeration station.

8. The method according to claim 2, characterized in that, According to the constructed return air flow model: Determine the chilled water supply for the water-cooled plates. Chilled water supply to the return air heat exchanger ; In the formula, This is the difference between the heat of inlet water and the heat of return water for the water-cooled plate; For the specific heat capacity of water, The specific gravity of water, The return water temperature of the water-cooled plate. The emulsion supply for the hydraulic support flowing through the return air heat exchanger. The specific heat capacity of the emulsion. To supply temperature to the emulsion of the hydraulic support. The emulsion outlet temperature of the hydraulic support. The return water temperature of the chilled water in the return air heat exchanger; To supply temperature for the chilled water in the refrigeration station.

9. The system according to claim 2, characterized in that, There are multiple water-cooled plates, which are arranged at intervals along the width of the coal mining face and connected in series.

10. The system according to any one of claims 1-9, characterized in that, The refrigeration station forms independent cooling cycles with the intake air cooling unit and the return air cooling unit through two parallel branches; or, The intake air cooling unit and the return air cooling unit form independent cooling cycles with the independent refrigeration stations set on the intake side and return air side, respectively.

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