A method for determining tunnel air volume

Abstract

The present invention relates to the technical field of underground mine ventilation and provides a method for determining tunnel air volume, comprising: constructing a three-dimensional ventilation network model for an underground mine; measuring actual tunnel ventilation data, calculating tunnel frictional wind resistance, and inversely calculating the tunnel frictional resistance coefficient to correct the three-dimensional ventilation network model; online monitoring of the main tunnel wind speed and integrating it into the three-dimensional ventilation network model; correcting the online monitored wind speed of the main tunnel to the average wind speed of the entire cross-section and calculating the monitored air volume; interpolating the monitored air volume of the main tunnel into the corresponding tunnel in the three-dimensional ventilation network model, replacing the air volume calculated by the model with the monitored air volume, calculating the air volume of other tunnels using the interpolated three-dimensional ventilation network model, and inversely calculating the tunnel wind speed based on the air volume and cross-sectional area. The present invention can realize the real-time calculation of air volume using online monitoring data, greatly improving the accuracy and efficiency of tunnel air volume determination, and realizing that the accurate air volume of all tunnels can be obtained by monitoring the wind speed of the main tunnel, thereby reducing the cost of tunnel air volume determination.

Description

Technical Field

[0001] The present invention relates to the technical field of underground mine ventilation, and in particular to a method for determining tunnel air volume. Background Art

[0002] Underground mine ventilation systems are dynamic, changing with production changes. Existing methods for determining roadway air volume typically involve first constructing a ventilation network model and then using the model to calculate the air volume. However, these methods perform static model calculations without considering real-time online monitoring data. Consequently, the calculated air volume data deviates significantly from the measured ventilation data, failing to accurately reflect underground ventilation conditions and, consequently, to timely reflect changes in underground air volume. This hinders ventilation management personnel from quickly developing reliable air adjustment plans, reducing ventilation emergency management capabilities. Summary of the Invention

[0003] In response to the problems existing in the prior art, the present invention provides a method for determining the tunnel air volume, which can realize the real-time calculation of the air volume by incorporating online monitoring data, greatly improving the accuracy and efficiency of the tunnel air volume determination. It can also obtain the accurate air volume of all tunnels by monitoring the wind speed of the main tunnels, thereby reducing the cost of tunnel air volume determination.

[0004] The technical solution of the present invention is:

[0005] A method for determining the air volume in a roadway comprises the following steps:

[0006] Step 1: Construct a 3D ventilation network model for the mine;

[0007] The three-dimensional ventilation network model distributes the air volume of the tunnel network according to the air volume balance, wind pressure balance and tunnel friction wind resistance. The friction resistance coefficient used in the calculation of tunnel friction wind resistance is preliminarily set according to the tunnel design manual.

[0008] Step 2: Modify the 3D ventilation network model based on measured ventilation data

[0009] Measure the actual ventilation data of the tunnel, calculate the tunnel frictional wind resistance based on the actual ventilation data, inversely calculate the tunnel friction resistance coefficient based on the tunnel frictional wind resistance, and obtain a corrected friction resistance coefficient. Use the corrected friction resistance coefficient to replace the friction resistance coefficient initially set in the three-dimensional ventilation network model to correct the three-dimensional ventilation network model;

[0010] Step 3: Online monitoring of wind speed in main tunnels and integration into the 3D ventilation network model

[0011] Install wind speed sensors at designated installation points in the cross-sections of the main tunnels. Use the wind speed sensors to monitor the wind speed in the tunnel cross-sections in real time. Connect the real-time monitored wind speed data to the corresponding tunnels in the three-dimensional ventilation network model according to the tunnel numbers.

[0012] Step 4: Correct the online monitoring wind speed of the main lanes and calculate the monitoring air volume

[0013] Determine a relationship function between the wind speed at the installation location of the wind speed sensor and the average wind speed of the entire roadway section based on the wind speed characteristics of the roadway section; calculate the average wind speed of the entire roadway section using the relationship function based on the wind speed data monitored in real time by all wind speed sensors at the cross section of the main roadway; and calculate the monitored air volume based on the average wind speed of the entire roadway section and the cross-sectional area of ​​the roadway;

[0014] Step 5: Interpolate the main laneway monitoring air volume and solve the air volume of other lanes

[0015] The monitored air volume of the main lane is interpolated into the corresponding lane in the three-dimensional ventilation network model, and the air volume data calculated by the three-dimensional ventilation network model is replaced by the monitored air volume. The interpolated three-dimensional ventilation network model is used to calculate the air volume of other lanes, and the wind speed of the lane is reversed based on the air volume and cross-sectional area of ​​other lanes.

[0016] Furthermore, the step 1 specifically includes the following steps:

[0017] Step 1.1: Use DIMINE digital mining software to extract the tunnel centerline;

[0018] Step 1.2: Import the extracted lane centerline into the iVent ventilation optimization platform;

[0019] Step 1.3: Set the categories of the lane centerline; the categories include internal lanes, air intake lanes, return air lanes, and dead-end closed lanes. Dead-end closed lanes are not included in the network solution.

[0020] Step 1.4: Sort out the unconnected lanes and ensure that each lane is connected to a network;

[0021] Step 1.5: Enter wind resistance parameters including friction resistance coefficient, tunnel cross-sectional area, and tunnel perimeter. Calculate tunnel length based on tunnel centerline. Calculate tunnel friction resistance based on wind resistance parameters and tunnel length. Allocate tunnel network air volume based on air volume balance, wind pressure balance, and tunnel friction resistance.

[0022] Step 1.6: Check the ventilation network according to the topological logical relationship of the ventilation network, correct the logical relationship errors, and obtain the correct topological logical relationship ventilation network;

[0023] Step 1.7: Add known ventilation facilities to the ventilation network;

[0024] Step 1.8: Enter the fan characteristic curve provided by the fan factory or the measured characteristic curve into the fan database.

[0025] Furthermore, in step 2, actual ventilation data of the tunnel is measured, the tunnel frictional wind resistance is calculated based on the actual ventilation data, and the tunnel friction resistance coefficient is inversely calculated based on the tunnel frictional wind resistance, specifically including:

[0026] The actual ventilation data of the measured tunnel include tunnel cross-sectional dimensions and elevation of each measuring point in the cross-sectional area, wind speed v, air density, and absolute pressure;

[0027] Calculate the cross-sectional area S and perimeter U of the tunnel according to the tunnel cross-sectional dimensions, calculate the tunnel cross-sectional air volume Q = Sv, and calculate the velocity pressure difference between the two points i and j in the tunnel. Potential pressure difference Δh 位i-j =Z i gρ i -Z j gρ j ; where ρ i is the air density at point i, ρ j is the air density at point j, v i is the wind speed at point i, v j is the wind speed at point j, Z i is the elevation of point i, Z j is the elevation of point j, g is the acceleration due to gravity;

[0028] Calculate the ventilation resistance h of the measuring section between points i and j in the tunnel ij =(ΔP i -ΔP j )-(ΔP 0i -ΔP 0j )+Δh 速i-j +Δh 位i-j , and thus calculate the frictional wind resistance R of the measuring section between points i and j in the tunnel ij =h ij / Q ij 2 ; where ΔP i is the static pressure difference at point i, ΔP j is the static pressure difference at point j, ΔP oi is the static pressure difference of the reference point when measuring pressure at point i, ΔP 0j Q is the static pressure difference of the reference point when measuring pressure at point j, ij is the air volume between points i and j. When there is no branch or air leakage between the two measuring points, Q ij =(Q i +Q j ) / 2, when there is a branch between the two measuring points and the measuring point is set before the intersection of the wind flow and the wind flow. ij =Q j When there is a branch between the two measuring points and the measuring point is set after the intersection of the wind flow and the wind flow, Q ij =Q i , Q i is the air volume at point i, Qj is the air volume at point j;

[0029] According to the friction wind resistance of the roadway, the friction resistance coefficient of the roadway is calculated by back-calculating the friction resistance coefficient of the roadway to obtain the corrected friction resistance coefficient of the measuring section between points i and j in the roadway ∝ ij =R ij S 3 / L ij U; among them, L ij is the length of the tunnel between points i and j.

[0030] Furthermore, in step 2, ventilation data in spring, summer, autumn and winter are measured respectively, and the three-dimensional ventilation network model is corrected in sequence using the measured ventilation data.

[0031] Furthermore, in step 5, the three-dimensional ventilation network model is solved at intervals of time t, and an alarm is issued when the average wind speed of the entire section of the main tunnel, the monitored air volume, and the solved air volume and wind speed of other tunnels exceed the preset wind speed threshold or the air volume exceeds the preset wind volume threshold.

[0032] The beneficial effects of the present invention are:

[0033] The present invention calculates the frictional wind resistance of the tunnel by measuring the actual ventilation data of the tunnel, and then inversely calculates the friction resistance coefficient to preliminarily correct the three-dimensional ventilation network model. The wind speed of the main tunnel section is monitored and the wind speed at the installation position of the wind speed sensor is corrected to the average wind speed of the entire tunnel section to calculate the monitoring air volume. The monitored air volume of the main tunnel is interpolated into the three-dimensional ventilation network model to solve the air volume of other tunnels, and the online monitoring data is used to participate in the real-time solution of the air volume, which greatly improves the accuracy and efficiency of the tunnel air volume determination. The obtained air volume data can accurately reflect the underground ventilation conditions and timely reflect the changes in the underground air volume, assisting ventilation management personnel to make quick decisions and formulate reliable air adjustment plans, improving the ventilation emergency management capabilities, and only need to monitor the wind speed of the main tunnel to obtain the accurate air volume of all tunnels, reducing the monitoring cost, thereby reducing the cost of determining the tunnel air volume. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is a flow chart of the method for determining the tunnel air volume of the present invention.

[0035] Figure 2 It is a schematic diagram of the center line of the lane after the lane is sorted out in a specific implementation method.

[0036] Figure 3 Schematic diagram of the locations of tunnel section measuring points in a specific implementation method.

[0037] Figure 4 Schematic diagram of wind speed characteristics of a certain tunnel section with an average wind speed of 3 m / s in a specific implementation manner.

[0038] Figure 5 This is a schematic diagram of the principle of using ventilation online monitoring data to participate in the solution of the three-dimensional ventilation network model in a specific implementation method. DETAILED DESCRIPTION

[0039] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0040] like Figure 1 As shown, the method for determining the roadway air volume of the present invention includes the following steps:

[0041] Step 1: Construct a 3D ventilation network model for the mine;

[0042] The three-dimensional ventilation network model distributes the air volume of the tunnel network according to the air volume balance, wind pressure balance and tunnel friction wind resistance. The friction resistance coefficient used in the calculation of tunnel friction wind resistance is preliminarily set according to the tunnel design manual.

[0043] Step 2: Modify the 3D ventilation network model based on measured ventilation data

[0044] Measure the actual ventilation data of the tunnel, calculate the tunnel frictional wind resistance based on the actual ventilation data, inversely calculate the tunnel friction resistance coefficient based on the tunnel frictional wind resistance, and obtain a corrected friction resistance coefficient. Use the corrected friction resistance coefficient to replace the friction resistance coefficient initially set in the three-dimensional ventilation network model to correct the three-dimensional ventilation network model;

[0045] Step 3: Online monitoring of wind speed in main tunnels and integration into the 3D ventilation network model

[0046] Install wind speed sensors at designated installation points in the cross-sections of the main tunnels. Use the wind speed sensors to monitor the wind speed in the tunnel cross-sections in real time. Connect the real-time monitored wind speed data to the corresponding tunnels in the three-dimensional ventilation network model according to the tunnel numbers.

[0047] Step 4: Correct the online monitoring wind speed of the main lanes and calculate the monitoring air volume

[0048] Determine a relationship function between the wind speed at the installation location of the wind speed sensor and the average wind speed of the entire roadway section based on the wind speed characteristics of the roadway section; calculate the average wind speed of the entire roadway section using the relationship function based on the wind speed data monitored in real time by all wind speed sensors at the cross section of the main roadway; and calculate the monitored air volume based on the average wind speed of the entire roadway section and the cross-sectional area of ​​the roadway;

[0049] Step 5: Interpolate the main laneway monitoring air volume and solve the air volume of other lanes

[0050] The monitored air volume of the main lane is interpolated into the corresponding lane in the three-dimensional ventilation network model, and the air volume data calculated by the three-dimensional ventilation network model is replaced by the monitored air volume. The interpolated three-dimensional ventilation network model is used to calculate the air volume of other lanes, and the wind speed of the lane is reversed based on the air volume and cross-sectional area of ​​other lanes.

[0051] In this embodiment, the tunnel air volume determination method of the present invention is used to determine the tunnel air volume in a certain mining area.

[0052] First, a 3D ventilation network model was constructed based on the iVent mine ventilation software. The specific steps included:

[0053] Step 1.1: Extract the tunnel centerline using DIMINE digital mining software

[0054] The iVent mine ventilation system's air network is constructed based on roadway centerlines. A 3D roadway centerline model is constructed using DIMINE digital mining software. First, the development roadway centerlines are extracted. The development system includes major inclined shafts and vertical shafts. A 3D map of the mine's ventilation shafts and roadways is constructed based on the "Mining Atlas" provided by the mine. Next, starting from the upper middle section, the centerlines of the middle roadways are extracted one by one using DIMINE digital mining software. Next, the centerlines of the middle ventilation shafts are extracted. Without knowing whether the shafts are ventilated, they are first constructed into the 3D ventilation system. Later, based on confirmation, if they are no longer ventilated, they are converted to sealed roadways. Finally, a composite three-dimensional map of the shaft and roadway engineering is created, including the development shaft, middle roadways, and the middle ventilation shafts.

[0055] Step 1.2: Import the extracted lane centerline into the iVent ventilation optimization platform

[0056] The center lines extracted by the DIMINE digital mining platform do not establish a topological relationship for diversion. The extracted tunnel center lines need to be imported into the iVent ventilation optimization platform to sort out the ventilation network and establish a topological relationship for airflow.

[0057] Step 1.3: Set the category of the lane centerline; the categories include internal lanes, air intake lanes, return air lanes, and dead-end closed lanes. Dead-end closed lanes are not involved in the network solution.

[0058] When using the iVent ventilation optimization platform to perform ventilation network simulation, it is necessary to build all negative pressure ventilation lanes into the simulation system. Therefore, the lane center lines are classified. Based on the location and relationship of the lanes, ventilation lanes are divided into four categories: internal lanes, air intake lanes, return air lanes, and dead-end closed lanes.

[0059] Internal roadway: the roadway within the system negative pressure (positive pressure) ventilation network;

[0060] Inlet roadway: the roadway through which air enters the ventilation system from the surface;

[0061] Return airway: the roadway where air is discharged from the ventilation system to the surface;

[0062] Dead-end closed tunnel: In the tunnel network, tunnels that cannot be exhausted by the system negative pressure (positive pressure), such as excavation working faces and dead-end tunnels that are not through, as well as closed tunnels, are retained in the tunnel network but do not participate in the network solution.

[0063] Step 1.4: Sort out unconnected lanes and ensure that each lane is connected to a network

[0064] The center lines extracted by the DIMINE digital mining platform are not all connected to each other. The iVent ventilation optimization platform needs to check each lane to ensure that each lane has a logical connection. It is necessary to sort out the unconnected lanes and obtain a lane centerline diagram that connects each lane in a network. Figure 2 shown.

[0065] Step 1.5: Enter tunnel parameters

[0066] Enter wind resistance parameters, including friction coefficient, tunnel cross-sectional area, and tunnel perimeter. Calculate tunnel length based on tunnel centerline. Calculate tunnel friction resistance based on wind resistance parameters and tunnel length. Allocate tunnel network air volume based on air volume balance, wind pressure balance, and tunnel friction resistance. In a parallel network, greater resistance results in lower air volume, while lower resistance results in greater air volume.

[0067] Step 1.6: Check the ventilation network according to the ventilation network topology logic relationship, correct the logic relationship errors, and obtain the correct topology logic relationship ventilation network

[0068] Step 1.7: Add known ventilation facilities to the ventilation network

[0069] Ventilation facilities control air volume and flow and are key to achieving on-demand ventilation. After the network check passes, add known ventilation facilities to the network.

[0070] Step 1.8: Enter the fan characteristic curve provided by the fan manufacturer or the measured characteristic curve into the fan database, and perform network solution using the fan characteristic curve provided by the manufacturer or the measured characteristic curve.

[0071] The friction coefficient in the initially established three-dimensional ventilation network model was initially set according to the tunnel design manual. In practice, the friction coefficient is affected by various factors, leading to deviations between the friction coefficient set according to the tunnel design manual and the actual friction coefficient. This requires correcting the friction coefficient using measured ventilation data to optimize the three-dimensional ventilation network model. To correct the friction coefficient, the mine ventilation resistance must be measured. Common methods include the differential pressure gauge method and the barometer method. In this embodiment, the barometer point-by-point measurement method was chosen, owing to its small size and light weight, simple and quick on-site measurement, and labor-saving and time-saving. During the measurement, a CFZZ5 ventilation comprehensive parameter measuring instrument was placed near the surface wellhead as a base point barometer to monitor changes in surface air pressure. The base point detector automatically measured and recorded changes in atmospheric static pressure every minute. A separate CFZZ5 ventilation comprehensive parameter measuring instrument was brought underground to measure air pressure at each measuring point along a pre-selected measurement route. The instrument also measured parameters such as the tunnel cross-section, wind speed, and air temperature, until the measurement was complete and the instrument returned to the base point. The main measurement principle is: use a barometer to measure the absolute pressure between the measuring points, add the velocity pressure difference and the position pressure difference, and the ventilation resistance can be calculated. The underground field measurement team measures the wind speed, tunnel section size, support material and form at each measuring point according to the measurement plan, and records them. Each section measures 20 sets of data and takes the average value. For specific locations, see Figure 3 .

[0072] In this embodiment, the correction process of the friction resistance coefficient specifically includes:

[0073] The actual ventilation data measured in the tunnel includes the tunnel cross-sectional dimensions and the elevation of each measuring point, wind speed v, air density, and absolute pressure. Three actual wind speed measurements were taken at each measuring point, and the arithmetic mean was calculated as the average wind speed at that point. The resistance measuring instrument collected 20 sets of data for each cross-section to calculate the arithmetic mean.

[0074] Calculate the tunnel cross-sectional area S and perimeter U based on the tunnel cross-sectional dimensions.

[0075] Calculate the tunnel cross-sectional air volume Q=Sv.

[0076] Calculate the velocity and pressure difference between points i and j in the tunnel Potential pressure difference Δh 位i-j =Z i gρ i -Z j gρ j ; where ρ i is the air density at point i, ρ j is the air density at point j, v i is the wind speed at point i, v j is the wind speed at point j, Z i is the elevation of point i, Zj is the elevation of point j, and g is the acceleration due to gravity.

[0077] Calculate the ventilation resistance h of the measuring section between points i and j in the tunnel ij =(ΔP i -ΔP j )-(ΔP 0i -ΔP 0j )+Δh 速i-j +Δh 位i-j , and thus calculate the frictional wind resistance R of the measuring section between points i and j in the tunnel ij =h ij / Q ij 2 ; where ΔP i is the static pressure difference at point i, ΔP j is the static pressure difference at point j, ΔP oi is the static pressure difference of the reference point when measuring pressure at point i, ΔP 0j Q is the static pressure difference of the reference point when measuring pressure at point j, ij is the air volume between points i and j. When there is no branch or air leakage between the two measuring points, Q ij =(Q i +Q j ) / 2, when there is a branch between the two measuring points and the measuring point is set before the intersection of the wind flow and the wind flow. ij =Q j When there is a branch between the two measuring points and the measuring point is set after the intersection of the wind flow and the wind flow, Q ij =Q i , Q i is the air volume at point i, Q j is the air volume at point j.

[0078] According to the friction wind resistance of the roadway, the friction resistance coefficient of the roadway is calculated by back-calculating the friction resistance coefficient of the roadway to obtain the corrected friction resistance coefficient of the measuring section between points i and j in the roadway ∝ ij =R ij S 3 / L ij U: Among them, L ij is the length of the tunnel between points i and j.

[0079] In this embodiment, ventilation data in spring, summer, autumn and winter are measured respectively, and the three-dimensional ventilation network model is corrected in sequence using the ventilation data measured in spring, summer and autumn and winter, so that the three-dimensional ventilation network model can more accurately reflect the underground ventilation conditions.

[0080] Due to the large number of underground mine tunnels, monitoring the air volume in all of them is difficult due to the enormous human, material, and financial resources required. Therefore, this invention selects key tunnels for real-time air volume monitoring and uses the monitoring data from these key tunnels to calculate the air volume in other tunnels using a three-dimensional ventilation network model. This approach saves costs while achieving sufficient accuracy.

[0081] The present invention installs wind speed sensors at installation points set on the cross section of the main tunnel, and uses the wind speed sensors to monitor the wind speed of the tunnel cross section in real time. Figure 4 As shown, the wind speed at different locations in a tunnel section is generally different. Therefore, the data monitored by the wind speed sensor does not represent the average wind speed in the tunnel. Therefore, the wind speed needs to be further corrected based on the wind speed characteristics of the entire tunnel section. Specifically, a relationship function is determined based on the wind speed characteristics of the tunnel section to determine the wind speed at the wind speed sensor installation location and the average wind speed of the entire tunnel section. The relationship function is used to calculate the average wind speed of the entire tunnel section based on the wind speed data monitored in real time by all wind speed sensors at the main tunnel section. The monitored air volume is calculated based on the average wind speed of the entire section and the tunnel cross-sectional area.

[0082] After the wind speed is corrected in real time and the monitored air volume is obtained, it is necessary to interpolate the monitored air volume to the corresponding lane in the three-dimensional ventilation network model, and interpolate the monitored air volume and wind direction to the fixed monitored lane solution data, and use the monitored data to replace the original model static solution data. Use the ventilation online monitoring data to participate in the three-dimensional ventilation network model solution, such as Figure 5 As shown, wind speed sensors are used to monitor the wind speed of the main tunnel sections in real time. The three-dimensional ventilation network model obtains the wind speed parameters of the ventilation monitoring system, and after data correction, the wind speed parameters are automatically or manually solved as needed. By monitoring the wind speed of the main tunnels, dynamic and comprehensive monitoring and analysis of the ventilation system is achieved, reducing the investment and maintenance of the monitoring system, improving the comprehensiveness and stability of the monitoring system, and timely and comprehensively discovering underground ventilation problems, which is conducive to preventing and addressing underground ventilation safety issues. In this embodiment, in step 5, the three-dimensional ventilation network model is solved every 5 minutes. When the average wind speed of the entire section of the main tunnel, the monitored air volume, the solved air volume of other tunnels, and the wind speed exceed the preset wind speed threshold, or the air volume exceeds the preset air volume threshold, an alarm prompt is issued.

[0083] Obviously, the above embodiments are only some embodiments of the present invention, rather than all embodiments. The above embodiments are only used to explain the present invention and do not constitute a limitation on the scope of protection of the present invention. Based on the above embodiments, all other embodiments obtained by those skilled in the art without making creative work, that is, all modifications, equivalent substitutions and improvements made within the spirit and principles of this application, fall within the scope of protection claimed by the present invention.

Claims

1. A method for determining the air volume in a roadway, characterized in that: The steps include: Step 1: Construct a 3D ventilation network model for the mine; The three-dimensional ventilation network model distributes the air volume of the tunnel network according to the air volume balance, wind pressure balance and tunnel friction wind resistance. The friction resistance coefficient used in the calculation of tunnel friction wind resistance is preliminarily set according to the tunnel design manual. Step 2: Modify the 3D ventilation network model based on measured ventilation data Measure the actual ventilation data of the tunnel, calculate the tunnel frictional wind resistance based on the actual ventilation data, inversely calculate the tunnel friction resistance coefficient based on the tunnel frictional wind resistance, and obtain a corrected friction resistance coefficient. Use the corrected friction resistance coefficient to replace the friction resistance coefficient initially set in the three-dimensional ventilation network model to correct the three-dimensional ventilation network model; Step 3: Online monitoring of wind speed in main tunnels and integration into the 3D ventilation network model Install wind speed sensors at designated installation points in the cross-sections of the main tunnels. Use the wind speed sensors to monitor the wind speed in the tunnel cross-sections in real time. Connect the real-time monitored wind speed data to the corresponding tunnels in the three-dimensional ventilation network model according to the tunnel numbers. Step 4: Correct the online monitoring wind speed of the main lanes and calculate the monitoring air volume Determine a relationship function between the wind speed at the installation location of the wind speed sensor and the average wind speed of the entire roadway section based on the wind speed characteristics of the roadway section; calculate the average wind speed of the entire roadway section using the relationship function based on the wind speed data monitored in real time by all wind speed sensors at the cross section of the main roadway; and calculate the monitored air volume based on the average wind speed of the entire roadway section and the cross-sectional area of ​​the roadway; Step 5: Interpolate the main laneway monitoring air volume and solve the air volume of other lanes The monitored air volume of the main lane is interpolated into the corresponding lane in the three-dimensional ventilation network model, and the air volume data calculated by the three-dimensional ventilation network model is replaced by the monitored air volume. The interpolated three-dimensional ventilation network model is used to calculate the air volume of other lanes, and the wind speed of the lane is reversed based on the air volume and cross-sectional area of ​​other lanes.

2. The method for determining the roadway air volume according to claim 1, characterized in that: The step 1 specifically includes the following steps: Step 1.1: Use DIMINE digital mining software to extract the tunnel centerline; Step 1.2: Import the extracted lane centerline into the iVent ventilation optimization platform; Step 1.3: Set the categories of the lane centerline; the categories include internal lanes, air intake lanes, return air lanes, and dead-end closed lanes. Dead-end closed lanes are not included in the network solution. Step 1.4: Sort out the unconnected lanes and ensure that each lane is connected to a network; Step 1.5: Enter wind resistance parameters including friction resistance coefficient, tunnel cross-sectional area, and tunnel perimeter. Calculate tunnel length based on tunnel centerline. Calculate tunnel friction resistance based on wind resistance parameters and tunnel length. Allocate tunnel network air volume based on air volume balance, wind pressure balance, and tunnel friction resistance. Step 1.6: Check the ventilation network according to the topological logical relationship of the ventilation network, correct the logical relationship errors, and obtain the correct topological logical relationship ventilation network; Step 1.7: Add known ventilation facilities to the ventilation network; Step 1.8: Enter the fan characteristic curve provided by the fan factory or the measured characteristic curve into the fan database.

3. The method for determining the roadway air volume according to claim 1, characterized in that: In the step 2, actual ventilation data of the tunnel is measured, the tunnel frictional wind resistance is calculated based on the actual ventilation data, and the tunnel friction resistance coefficient is inversely calculated based on the tunnel frictional wind resistance, specifically including: The actual ventilation data of the measured tunnel include tunnel cross-sectional dimensions and elevation of each measuring point in the cross-sectional area, wind speed v, air density, and absolute pressure; Calculate the cross-sectional area S and perimeter U of the tunnel according to the tunnel cross-sectional dimensions, calculate the tunnel cross-sectional air volume Q = Sv, and calculate the velocity pressure difference between the two points i and j in the tunnel. Potential pressure difference Δh 位i-j =Z i gρ i -Z j gρ j ; where ρ i is the air density at point i, ρ j is the air density at point j, v i is the wind speed at point i, v j is the wind speed at point j, Z i is the elevation of point i, Z j is the elevation of point j, g is the acceleration due to gravity; Calculate the ventilation resistance h of the measuring section between points i and j in the tunnel ij =(ΔP i -ΔP j )-(ΔP 0i -ΔP 0j )+Δh 速i-j +Δh 位i-j , and thus calculate the frictional wind resistance R of the measuring section between points i and j in the tunnel ij =h ij / Q ij 2 ; where ΔP i is the static pressure difference at point i, ΔP j is the static pressure difference at point j, ΔP oi is the static pressure difference of the reference point when the pressure is measured at point i, ΔP0j is the static pressure difference of the reference point when the pressure is measured at point j, Q ij is the air volume between points i and j. When there is no branch or air leakage between the two measuring points, Q ij =(Q i +Q j ) / 2, when there is a branch between the two measuring points and the measuring point is set before the intersection of the wind flow and the wind flow. ij =Q j When there is a branch between the two measuring points and the measuring point is set after the intersection of the wind flow and the wind flow, Q ij =Q i , Q i is the air volume at point i, Q j is the air volume at point j; According to the friction wind resistance of the roadway, the friction resistance coefficient of the roadway is calculated by back-calculating the friction resistance coefficient of the roadway to obtain the corrected friction resistance coefficient of the measuring section between points i and j in the roadway ∝ ij =R ij S 3 / L ij U; among them, L ij is the length of the tunnel between points i and j.

4. The method for determining the roadway air volume according to claim 1, characterized in that: In step 2, ventilation data in spring, summer, autumn and winter are measured respectively, and the three-dimensional ventilation network model is corrected in sequence using the measured ventilation data.

5. The method for determining the roadway air volume according to claim 1, characterized in that: In step 5, the three-dimensional ventilation network model is solved at intervals of time t, and an alarm is issued when the average wind speed of the entire section of the main tunnel, the monitored air volume, and the solved air volume and wind speed of other tunnels exceed the preset wind speed threshold or the air volume exceeds the preset wind volume threshold.

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