Multi-factor atomization simulation method of coal mine environment dust prevention and control simulation system

Abstract

The invention discloses a coal mine environment dust prevention and control simulation system multi-factor atomization simulation method, which comprises the following steps: step 1, using Solid Works software to establish an equal-proportion geometric model, drawing the model as required, the geometric model being composed of a working face operation space, a water distribution pipe and a nozzle; the method comprises twelve steps. The invention relates to the technical field of coal mine dust prevention and control, in particular to a multi-factor atomization simulation method of a coal mine environment dust prevention and control simulation system, numerical simulation is performed through a DPM mathematical model, fog drops are regarded as discrete phases, a mathematical model is established through an Euler-Lagrange method, and the diffusion process of the fog drops of the coal mine environment dust prevention and control simulation system is simulated. In the coal mining process of the fully mechanized coal mining face, numerical simulation is carried out on a raw dust pollution area, the dust falling effect of fog drops under the action of different atomization angles and spraying pressure is studied, and a guarantee is provided for providing more reasonable spraying dust falling measures.

Description

Technical Field

[0001] The invention relates to the technical field of coal mine dust prevention and control, in particular to a multi-factor atomization simulation method for a coal mine environmental dust prevention and control simulation system. Background Art

[0002] The fully mechanized mining face is one of the important sources of dust in coal mines. Compared with the total dust generated in coal mines, the fully mechanized mining face accounts for more than 60% of the dust generated. With the continuous improvement of the automation level of the working face, the production efficiency of the working face continues to increase; at the same time, the dust concentration generated by the coal mining and tunneling working face is also increasing. The dust generated by the working face will pose a serious threat to the physical and mental health of the workers.

[0003] At present, the main means of dust reduction for fully mechanized mining working faces is spray dust reduction. Spray dust reduction is a measure that, during the coal mining process, spray groups are deployed in different dust-producing areas, and the water curtain is used to isolate and the collision behavior between dust particles and droplet particles is used to settle the dust, ultimately achieving the purpose of dust reduction.

[0004] The research reports related to the prior art mainly include: CN210021529U discloses a spray dust suppression device for underground coal mines, in which the up and down reciprocating motion of the baffle plate of the device achieves the up and down reciprocating motion of the traction spray head; CN2647437Y discloses a spray nozzle of a blast furnace gas waste pressure power generation turbine device, in which the water flow forms throttling and expansion flow in the spray nozzle, and finally forms an atomization effect of the water flow.

[0005] In the research on simulation of dust control in coal mine environment, the related patent disclosures in the prior art mainly include: CN117831656A discloses a numerical method for simulating the dust reduction effect of spraying on coal mining working face.

[0006] However, the existing numerical simulation research on dust control in coal mine environment is limited to the single setting of spray pressure and atomization angle, which is too simple; the spray dust suppression device has a complex structure and complex operation; the nozzle design is not optimized, resulting in poor atomization effect and affecting the dust suppression efficiency; if the spray device is not operated properly, it may affect the dust suppression effect, which requires certain technical training and expertise; the spray system has high requirements on water quality. If the water quality is poor, it may affect the spray effect and cause equipment damage. Summary of the invention

[0007] The present invention aims to provide a multi-factor atomization simulation method for a coal mine environmental dust control simulation system. Numerical simulation is performed through the DPM mathematical model, the droplets are regarded as discrete phases, and a mathematical model is established using the Euler-Lagrange method to simulate the diffusion process of droplets in the coal mine environmental dust control simulation system, so as to provide a guarantee for proposing more reasonable spray dust reduction measures.

[0008] To achieve the above objectives, the present invention is implemented through the following technical solutions: a multi-factor atomization simulation method for a coal mine environment dust prevention and control simulation system, comprising the following steps:

[0009] Step 1: Use Solid Works software to build a proportional geometric model. The model is drawn according to the requirements. The geometric model consists of a working space on the work surface, a water distribution pipe, and a sprinkler.

[0010] Step 2: Import the file into Mesh, divide the mesh using tetrahedral meshes according to the curvature size of the mesh and the minimum size between adjacent meshes, and perform mesh independence test to ensure that the best mesh solution is used during calculation;

[0011] Step 3: Import the final mesh solution into Fluent. First, adjust the scale to ensure that the size of the physical model is consistent with the actual size and check the mesh quality.

[0012] Step 4: First open the steady-state environment in Fluent and enable the k-ε model;

[0013] Step 5: Set the initial flow conditions and simulate the flow. After the calculation is completed, export the data and case files of the wind flow field.

[0014] Step 6: Import the exported wind flow field data and case files into Fluent again, convert the steady-state environment into a transient environment, and set the gravity acceleration according to the model direction;

[0015] Step 7: Open the discrete phase model and determine the coordinates of an injection point;

[0016] Step 8. Select the nozzle type and spray direction, and set parameters such as mass flow rate, atomization half angle, and spray pressure;

[0017] Step 9. Set the DPM wall condition and select escape;

[0018] Step 10. Open the Autosave tab and set the automatic save time interval based on the simulation time.

[0019] Step 11: Set the Time Step Size and Number of Time Steps to select an appropriate simulation duration while ensuring simulation accuracy;

[0020] Step 12: Import the automatically saved data file and case file into CFD-Post, and analyze the droplet spatiotemporal evolution diagram, droplet concentration distribution diagram under different atomization angles, and droplet concentration distribution diagram under different pressures in CFD-Post.

[0021] Preferably, the length, width and height of the working space model are preferably: 8m×3m×3m.

[0022] Preferably, the mass flow rate of the nozzle in step eight is preferably set to 0.048 kg / s, the atomization half angles are selected to be 15°, 20°, and 25°, respectively, the spray pressures are 1 MPa, 1.5 MPa, and 2 MPa, respectively, and the spray time is 2 s.

[0023] Preferably, the mathematical model of the airflow-dust migration process in the fully mechanized mining face includes very complex discrete phase equations and particle phase force balance equations.

[0024] The discrete phase equation is:

[0025]

[0026]

[0027] Where: Fd is the unit drag of the droplet (N); u is the continuous phase velocity (m / s); u p is the droplet velocity (m / s); μ is the fluid dynamic viscosity (N·s / m 2 ); ρ is the fluid density (kg / m 3 );ρ ρ is the droplet density (kg / m 3 );d p is the droplet diameter (m); Re is the Reynolds number; C d is the drag coefficient; g is the acceleration due to gravity (m / s 2 ); F is other forces (N).

[0028] The particle phase force balance equation is:

[0029]

[0030] In the formula, m p —Droplet mass (mg); u p —Droplet migration speed (m·s-1); ∑F—resultant force on the droplet (N); F d —Drag force on the droplets (N); F g —Gravity of the droplets (N); F f —Buoyancy of the droplets (N); Fx—other forces acting on the droplets (N).

[0031] The multi-factor atomization simulation method of the coal mine environment dust control simulation system also includes a geometric model of the coal mine environment dust control simulation system, including a simulation shell, the simulation shell is composed of a main shell of a rectangular structure, a pyramid installed at the end of the main shell, and an air inlet arranged at the end of the pyramid;

[0032] It also includes a plurality of nozzles, which are evenly distributed on the upper side and both sides of the main shell;

[0033] The inner ends of the plurality of spray heads are embedded in the main shell, the outer ends of the plurality of spray heads are connected with a plurality of water distribution pipes, and the ends of the plurality of water distribution pipes are connected with a main water supply pipe.

[0034] Preferably, a main control valve is provided on the main water supply pipe, and the main control valve is used to control the switch of water inlet.

[0035] Preferably, an air intake fan is provided on one side of the air inlet, and the air intake fan is used to simulate the amount of dust on the working surface.

[0036] Beneficial effects of the present invention: The multi-factor atomization simulation method of the coal mine environmental dust control simulation system is numerically simulated through the DPM mathematical model. First, the droplets are regarded as discrete phases, and the Euler-Lagrange method is used to establish a mathematical model to simulate the diffusion process of the droplets in the coal mine environmental dust control simulation system. In the coal mining process of the fully mechanized working face, the present invention provides a method for numerically simulating the original dust pollution area, studying the dust reduction effect of the droplets under different atomization angles and spray pressures, providing a guarantee for proposing more reasonable spray dust reduction measures, and providing effective technical support for dust control, which has very important practical significance. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 This is a multi-factor atomization simulation flow chart of the coal mine environment dust prevention and control simulation system of the present invention.

[0038] Figure 2 The concentration distributions of 15° and 20° atomization half angles at 1MPa, 1.5MPa and 2MPa of a multi-factor atomization simulation method of a coal mine environment dust control simulation system described in the present invention.

[0039] Figure 3 It is a first stereoscopic diagram of the coal mine environment dust prevention and control simulation system of the present invention.

[0040] Figure 4 This is a second stereoscopic diagram of the coal mine environment dust prevention and control simulation system of the present invention.

[0041] Figure 5 Based Figure 3 A partial cross-sectional view of .

[0042] In the figure: 1. Simulated shell; 2. Nozzle; 3. Water distribution pipe; 4. Main water supply pipe; 5. Main control valve; 6. Inlet fan; 11. Main shell; 12. Pyramid; 13. Air inlet. DETAILED DESCRIPTION

[0043] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. 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 creative work are within the scope of protection of the present invention.

[0044] like Figure 1-2 As shown, a multi-factor atomization simulation method for a coal mine environment dust prevention and control simulation system includes the following steps:

[0045] Step 1: Use Solid Works software to build a proportional geometric model, which consists of a working surface, a water distribution pipe, and a sprinkler.

[0046] Step 2: Import the file into Mesh, divide the mesh using tetrahedral meshes according to the curvature size of the mesh and the minimum size between adjacent meshes, and perform mesh independence test to ensure that the best mesh solution is used during calculation;

[0047] Step 3: Import the final mesh solution into Fluent. First, adjust the scale to ensure that the size of the physical model is consistent with the actual size and check the mesh quality.

[0048] Step 4: First open the steady-state environment in Fluent and enable the k-ε model;

[0049] Step 5: Set the initial flow conditions and simulate the flow. After the calculation is completed, export the data and case files of the wind flow field.

[0050] Step 6: Import the exported wind flow field data and case files into Fluent again, convert the steady-state environment into a transient environment, and set the gravity acceleration according to the model direction;

[0051] Step 7: Open the discrete phase model and determine the coordinates of an injection point;

[0052] Step 8. Select the nozzle type and spray direction, and set parameters such as mass flow rate, atomization half angle, and spray pressure;

[0053] Step 9. Set the DPM wall condition and select escape;

[0054] Step 10. Open the Autosave tab and set the automatic save time interval based on the simulation time.

[0055] Step 11: Set the Time Step Size and Number of Time Steps to select an appropriate simulation duration while ensuring simulation accuracy;

[0056] Step 12: Import the automatically saved data file and case file into CFD-Post, and analyze the droplet spatiotemporal evolution diagram, droplet concentration distribution diagram under different atomization angles, and droplet concentration distribution diagram under different pressures in CFD-Post.

[0057] The length, width and height of the working space model are preferably: 8m×3m×3m.

[0058] The mass flow rate of the nozzle in step eight is preferably set to 0.048 kg / s, the atomization half angles are selected to be 15°, 20°, and 25°, the spray pressures are 1 MPa, 1.5 MPa, and 2 MPa, and the spray time is 2 s.

[0059] The mathematical model of the airflow-dust migration process in the fully mechanized mining face is very complex, including the discrete phase equation and the particle phase force balance equation.

[0060] The discrete phase equation is:

[0061]

[0062] Where: Fd is the unit drag of the droplet (N); u is the continuous phase velocity (m / s); u p is the droplet velocity (m / s); μ is the fluid dynamic viscosity (N·s / m 2 ); ρ is the fluid density (kg / m 3 );ρ ρ is the droplet density (kg / m 3 );d p is the droplet diameter (m); Re is the Reynolds number; C d is the drag coefficient; g is the acceleration due to gravity (m / s 2 ); F is other forces (N).

[0063] The particle phase force balance equation is:

[0064]

[0065] In the formula, m p —Droplet mass (mg); u p —Droplet migration speed (m·s-1); ∑F—resultant force on the droplet (N); F d —Drag force on the droplets (N); F g —Gravity of the droplets (N); F f —Buoyancy of the droplets (N); Fx—other forces acting on the droplets (N).

[0066] like Figure 3-4It can be seen that in order to simulate the dust environment of the fully mechanized mining face of a coal mine more realistically, the present application also relates to a geometric model of a coal mine environmental dust control simulation system, which is applied to a multi-factor atomization simulation method of a coal mine environmental dust control simulation system. The geometric model of the coal mine environmental dust control simulation system includes a simulation shell 1, which is composed of a main shell 11 of a rectangular structure, a pyramid 12 installed at the end of the main shell 11, and an air inlet 13 arranged at the end of the pyramid 12; and also includes a plurality of nozzles 2, which are evenly distributed on the upper side and both sides of the main shell 11.

[0067] The inner ends of the plurality of spray heads 2 are embedded in the main housing 11, the outer ends of the plurality of spray heads 2 are connected to a plurality of water distribution pipes 3, and the ends of the plurality of water distribution pipes 3 are connected to a main water supply pipe 4. The angle of setting the spray heads is adjustable.

[0068] A main control valve 5 is provided on the main water supply pipe 4, and the main control valve 5 is used to control the switch of water inlet.

[0069] An air intake fan 6 is provided on one side of the air inlet 13. The air intake fan 6 is used to simulate the amount of dust on the working face. The air intake volume of the air intake fan is set under the simulated environment, and the air intake is set to dusty gas, and the dust content in the dusty gas is set. Then, the main shell is used to simulate the space on one side of the comprehensive mining working face where the workers are located. The pyramid 12 between the two is used to simulate the connection between the mining face and the rear space.

[0070] During the simulation, the switch and amount of water inlet can be controlled by the main control valve, and the water inlet simulation can be diverted to several water distribution pipes through the main water supply pipe. The spraying pressure and water volume are controlled by several water distribution pipes. The spraying of water mist is simulated through the nozzle to make the water mist reduce the simulated dust gas. The simulation results are obtained by calculating the discrete phase equation and the particle phase force balance equation.

[0071] From the above, it can be generally known that the multi-factor atomization simulation method of the coal mine environmental dust control simulation system is numerically simulated through the DPM mathematical model. First, the droplets are regarded as discrete phases, and the Euler-Lagrange method is used to establish a mathematical model to simulate the diffusion process of the droplets in the coal mine environmental dust control simulation system. In the coal mining process of the fully mechanized working face, the present invention provides a method for numerically simulating the original dust pollution area, studying the dust reduction effect of the droplets under different atomization angles and spray pressures, providing a guarantee for proposing more reasonable spray dust reduction measures, and providing effective technical support for dust control, which has very important practical significance.

[0072] Although 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 the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A multi-factor atomization simulation method for a coal mine environment dust control simulation system, characterized in that: The steps include: Step 1: Use Solid Works software to build a proportional geometric model. The model is drawn according to the requirements. The geometric model consists of a working space on the work surface, a water distribution pipe, and a sprinkler. Step 2: Import the file into Mesh, divide the mesh using tetrahedral meshes according to the curvature size of the mesh and the minimum size between adjacent meshes, and perform mesh independence test to ensure that the best mesh solution is used during calculation; Step 3: Import the final mesh solution into Fluent. First, adjust the scale to ensure that the size of the physical model is consistent with the actual size and check the mesh quality. Step 4: First open the steady-state environment in Fluent and enable the k-ε model; Step 5: Set the initial flow conditions and simulate the flow. After the calculation is completed, export the data and case files of the wind flow field. Step 6: Import the exported wind flow field data and case files into Fluent again, convert the steady-state environment into a transient environment, and set the gravity acceleration according to the model direction; Step 7: Open the discrete phase model and determine the coordinates of an injection point; Step 8. Select the nozzle type and spray direction, and set parameters such as mass flow rate, atomization half angle, and spray pressure; Step 9. Set the DPM wall condition and select escape; Step 10. Open the Autosave tab and set the automatic save time interval based on the simulation time. Step 11: Set the Time Step Size and Number of Time Steps to select an appropriate simulation duration while ensuring simulation accuracy; Step 12: Import the automatically saved data file and case file into CFD-Post, and analyze the droplet spatiotemporal evolution diagram, droplet concentration distribution diagram under different atomization angles, and droplet concentration distribution diagram under different pressures in CFD-Post.

2. The multi-factor atomization simulation method of a coal mine environment dust prevention and control simulation system according to claim 1 is characterized in that: The length, width and height of the working space model are preferably: 8m×3m×3m.

3. The multi-factor atomization simulation method of a coal mine environment dust prevention and control simulation system according to claim 2 is characterized in that: The mass flow rate of the nozzle in step eight is preferably set to 0.048 kg / s, the atomization half angles are selected to be 15°, 20°, and 25°, the spray pressures are 1 MPa, 1.5 MPa, and 2 MPa, and the spray time is 2 s.

4. The multi-factor atomization simulation method of a coal mine environment dust prevention and control simulation system according to claim 3 is characterized in that: The mathematical model of the wind flow-dust migration process in the fully mechanized mining face includes very complex discrete phase equations and particle phase force balance equations.

5. The multi-factor atomization simulation method of a coal mine environment dust prevention and control simulation system according to claim 3 is characterized in that: The discrete phase equation is: Where: Fd is the unit drag of the droplet (N); u is the continuous phase velocity (m / s); u p is the droplet velocity (m / s); μ is the fluid dynamic viscosity (N·s / m 2 ); ρ is the fluid density (kg / m 3 );ρ ρ is the droplet density (kg / m 3 );d p is the droplet diameter (m); Re is the Reynolds number; C d is the drag coefficient; g is the acceleration due to gravity (m / s 2 ); F is other forces (N).

6. The multi-factor atomization simulation method of a coal mine environment dust prevention and control simulation system according to claim 3 is characterized in that: The particle phase force balance equation is: In the formula, m p —Droplet mass (mg); u p —Droplet migration speed (m·s-1); ∑F—resultant force on the droplet (N); F d —Drag force on the droplets (N); F g —Gravity of the droplets (N); F f —Buoyancy of the droplets (N); Fx—other forces acting on the droplets (N).

7. A multi-factor atomization simulation method for a coal mine environment dust control simulation system, characterized in that: Also included is a geometric model of a coal mine environment dust prevention and control simulation system, comprising a simulation housing (1), wherein the simulation housing (1) is composed of a main housing (11) of a rectangular structure, a pyramid (12) installed at the end of the main housing (11), and an air inlet (13) arranged at the end of the pyramid (12); It also comprises a plurality of spray heads (2), wherein the plurality of spray heads (2) are evenly distributed around the upper side and both sides of the main shell (11); The inner ends of the plurality of spray heads (2) are embedded in the main housing (11), the outer ends of the plurality of spray heads (2) are connected to a plurality of water distribution pipes (3), and the ends of the plurality of water distribution pipes (3) are connected to a main water supply pipe (4).

8. The multi-factor atomization simulation method of a coal mine environment dust prevention and control simulation system according to claim 7 is characterized in that: The main water supply pipe (4) is provided with a main control valve (5), and the main control valve (5) is used to control the switch of water inlet.

9. The multi-factor atomization simulation method of a coal mine environment dust prevention and control simulation system according to claim 8, characterized in that: An air intake fan (6) is provided on one side of the air intake port (13), and the air intake fan (6) is used to simulate the amount of dust raised on the working surface.

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