CN111691910A - Coal mine adjusting air window capable of accurately determining ventilation volume - Google Patents
Coal mine adjusting air window capable of accurately determining ventilation volume Download PDFInfo
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21F—SAFETY DEVICES, TRANSPORT, FILLING-UP, RESCUE, VENTILATION, OR DRAINING IN OR OF MINES OR TUNNELS
- E21F1/00—Ventilation of mines or tunnels; Distribution of ventilating currents
- E21F1/10—Air doors
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
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- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
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Abstract
A coal mine adjusting air window capable of accurately determining ventilation volume belongs to the technical field of coal mine ventilation and comprises a sliding assembly, a window body, an air speed sensor and an auxiliary component, wherein the sliding assembly is composed of a synchronous belt, a speed measuring rod and a sliding rail, in order to solve the problem of accurate calculation of the ventilation volume of the coal mine adjusting air window, a speed monitoring point closest to the average speed of a ventilation surface is determined through a numerical simulation method, the speed sensor is arranged at the position, the speed monitoring point is gradually changed along with the change of the opening area of the adjusting air window, a synchronous belt structure is used for positioning the point, the speed measuring rod in the sliding assembly is enabled to be kept on the central axis of the opening area of the air window, the ventilation area of the air window is calculated, the air volume passing through the adjusting air window is finally and accurately calculated, and then a theoretical method is used for establishing an opening ventilation resistance coefficient (o) And let outCoefficient of resistance to ventilation leakage (R)l) And the air volume values under theoretical conditions are calculated by two paths, and finally the two paths are compared, and the error is within 10 percent, so that the method for accurately calculating the air volume is feasible.
Description
The technical field is as follows:
the patent relates to a colliery of accurate definite air volume adjusts wind window belongs to mine ventilation technical field.
Background art:
mine ventilation plays an extremely important role in coal mine production, and is a necessary condition for ensuring coal mine safety production and preventing accidents such as gas coal dust explosion and the like. The precondition of safe, reliable and continuous production of the mine is to have a reasonable and effective ventilation system, and to prevent accidents such as underground fire, gas explosion and the like to different degrees. The adjusting air window is an essential important infrastructure in a coal mine ventilation system, and is used for adjusting and controlling ventilation flow and creating conditions for the air quantity distribution of wind using places such as a mining working face and the like according to requirements. The quality of the air volume adjusting effect has great influence on the production safety, the running benefit and the working environment of the operating personnel.
In the ventilation facilities of the current mine ventilation system, the main types of the traditional adjusting air windows are fixed louver air windows, automatic adjustable louver air windows, push-pull adjusting air windows, manual inserting plate type adjusting air windows, impeller type precise scale adjusting air windows, key type precise scale adjusting air windows and digital scale air windows. The fixed louver consists of frame, louver, silk net, etc. and its louver has two opening modes, including forward opening mode and split opening mode, and the side of the adjustable louver has linked regulating mechanism for manual regulation and automatic regulation. The blades of the automatic adjustable louver window are fixed on the window frame through the crank linkage mechanism, the speed of the louver window passing through is measured through the sensor, then the signal is transmitted to the host, the host works on the electric actuator, and the louver window is adjusted through the crank link rod. The push-pull type adjusting air window is provided with the fixing device, the position of the adjusting plate can be fixed, and the push-pull type adjusting air window is simple to manufacture, attractive, reusable and convenient to install. Meanwhile, the continuous adjustment of the air quantity can be realized; the stability and the safety of the wind flow control are improved; the links of wood board processing and insertion are omitted, and the labor intensity is reduced; the time required by air volume regulation is shortened. The manual inserting plate type adjusting air window adopts an inserting plate link type structure in transmission, and realizes the control and management purpose of quantitative flow of air quantity in a stepless air adjusting mode through transmission of a hand wheel, a speed reducer, a chain wheel and the like in a rated ventilation area.
In the above-mentioned several kinds of wind windows, research is basically developed from the aspects of real-time monitoring of wind speed and automatic regulation of wind quantity, but the wind measuring position and calculation formula are not accurate during wind measurement, so that the calculation result of regulating the ventilation quantity of the wind window is not accurate enough. Based on the problems, the adjusting air window is designed, and a simpler and more accurate method is provided for mine ventilation and wind measurement.
The invention content is as follows:
the invention aims to solve the technical problem that the defects of the prior art are overcome, and provides a method for using a coal mine adjusting air window for accurately determining ventilation volume.
In order to achieve the purpose, the invention adopts the following technical scheme:
the invention provides a coal mine adjusting air window capable of accurately determining ventilation volume, which comprises four parts, namely a sliding assembly, a window body, an air speed sensor and an auxiliary component, wherein the sliding assembly comprises a sliding track, a synchronous belt and a speed measuring rod, the synchronous belt is connected with the speed measuring rod, the speed measuring rod is positioned at the central axis of the opening area of an adjusting air window, the speed sensor is positioned at the height position of 2/3 of the speed measuring rod, the accurate air volume is determined by an air speed value and the opening area of the air window, the accurate air volume is verified by applying a theoretical method, two ventilation air resistance coefficient paths are established for adjusting the air window, and the total ventilation resistance coefficient (R) is a total ventilation resistance coefficientt) The air quantity is formed by an opening ventilation resistance coefficient and a leakage ventilation resistance coefficient, and the theoretical air quantity is formed by air pressure and total ventilation resistance coefficient (R)t) And determining that the accurate air volume of the adjusting air window is compared with the calculated air volume. Finally, the accurate air volume value is determined by adjusting the air window.
The application method of the coal mine adjusting air window for accurately determining the ventilation volume comprises the following specific steps:
step 1: accurately positioning and adjusting a wind window speed monitoring point;
step 2: a wind window structure is improved, and the speed measuring rod is ensured to be positioned at the axis of the opening surface;
and step 3: obtaining accurate air volume;
and 4, step 4: defining the adjusting air window as a parallel air path, and calculating the opening ventilation resistance coefficient (R)0) An expression;
and 5: determining a ventilation resistance coefficient (R) for a louver leakl)；
Step 6: determining the total ventilation resistance coefficient of the air window, and solving a theoretical air quantity value;
and 7: and comparing the actually measured air volume with the theoretical air volume so as to judge whether the method is feasible or not.
Description of the drawings:
FIG. 1 is a flow chart of the invention for obtaining the total air volume of the coal mine adjusting air window;
FIG. 2 is a view showing the structure of the adjustable air window of the present invention
FIG. 3 is a schematic view of adjusting the air volume of the air window according to the present invention;
FIG. 4 is a schematic view of adjusting wind resistance of two paths of the wind windows according to the present invention;
FIG. 5 is a front view of an adjustable louver according to the present invention;
FIG. 6 is a left side view of an adjustable air window for use with the present invention;
fig. 7 is a top view of the adjustable louver of the present invention.
In the figure: 1-wind speed sensor, 2-synchronous belt, 3-tachometer rod, 4-push-pull handle, 5-synchronous belt fixing rod, 6-fixing bolt, 7-sliding track, 8-window opening area, 9-roadway total area, and 10-opening ventilation resistance coefficient (R)o) 11-coefficient of ventilation resistance to leakage (R)l)。
Detailed Description
The following detailed description of embodiments of the present invention is provided in connection with the accompanying drawings and examples. The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.
The method of this example is as follows.
Step 1: accurately finding the average speed of the ventilation area: numerical simulation research is carried out by utilizing computational fluid dynamics software Fluent, and numerical simulation calculation is carried out on the wind speed distribution condition at the ventilation area of the wind window. Establishing a two-dimensional model of the ventilation area of the air window in the ICEAM according to the actual size of the air window, dividing grids, outputting a calculation file, importing Fluent to perform numerical calculation, exporting a calculation result, performing Post-processing through CFD-Post and ORIGN, and acquiring data. And determining that the axial velocity in the ventilation area of the wind window is closest to the average velocity in the whole ventilation area. For further investigation, the simulation continues at each point on the mid-axis and the position on the tachometer bar 3 closest to the average speed of the entire ventilated surface is determined. And establishing a two-dimensional calculation model of the coal mine adjusting air window on the section of the central axis of the tunnel by using Fluent software, and simulating the speed distribution condition on the central line of the ventilation area of the adjusting air window. In the simulation process, 11 monitoring points are equidistantly arranged on the central axis of the wind window. The velocity at each monitoring point is shown in the table below.
The average wind speed of the ventilation area of the wind window is 5.0495m/s, and the eighth monitoring point is closer to the average wind speed. The error between the two is only 0.59 percent. Adjusting the opening area of the wind window for many times, finding that the rule is basically consistent, and if the width h of the wind window is set, determining that 2/3h (h is the height of the wind window) is provided with a monitoring point on the speed measuring rod 3 from top to bottom.
Step 2: reform transform the wind window structure, confirm the rectangle ventilation face center pin, confirm the point of testing the speed: the underground air window is arranged to be of a push-pull structure, the window body is fixed on a sliding rail 7, the air window is moved through a push-pull handle 4, and a speed measuring rod 3 is installed on the sliding rail 7 of the air window. In order to determine the central axis of the opening surface of the wind window, the speed measuring rod 3 is driven to transmit when the wind window needs to be pushed and pulled, and the displacement of the wind window movement is two times of the displacement of the speed measuring rod 3, and the displacement of the two accords with LWindow (Refreshment window)＝2LSpeed measuring rodThe relationship (2) of (c). Considering that in the actual production life, the synchronous belt 2 has the advantages of accurate transmission, small acting force on the shaft, compact structure and good wear resistance, the synchronous belt 2 is used for connecting the wind window and the speed measuring rod 3, so that the speed measuring rod 3 is kept at the central position of the opening area 8 of the wind window all the time. Since in step one it is clear that the position at the axis of the window opening area 8 is closest to the average speed of the entire ventilation surface, the speed lever 3 is marked here, whereWhen the wind window is actually measured, the measurement is carried out at the position.
And step 3: the wind speed sensor 1 used in the tunnel is arranged at 2/3h (h indicates the width of the wind window) of the height of the speed measuring rod 3 determined in the steps (1) and (2), and the accurate wind volume measured finally is obtained by using the known wind window opening area with Q ═ AV.
And 4, step 4: establishing an opening draft resistance coefficient (R) for a louvero)10 and coefficient of leakage ventilation resistance (R)l)11 two paths. Calculating the ventilation resistance coefficient (R) of the opening of the air windowo)10：
In the formula (I), the compound is shown in the specification,
N＝Ar/A；
the Z value was taken to be 2.5.
▽Ps＝RQ2(2)
Determining Q according to (1) and (2)
Then, from (2) and (3), R is determinedo
And 5: for practical situations, the leakage ventilation resistance coefficient (R) is determined according to the practical ventilation quantity, the wind pressure and the opening area 8 of the wind windowl)11 and the louver area 8. Determination of the ventilation resistance coefficient (R) for wind leakagel)11。
Firstly, the total resistance coefficient (R) of ventilation is calculated by measuring the pressure difference and the known wind quantityt) Then, the opening ventilation resistance coefficient (Ro)10 obtained in the step 3 is utilized, and finally, the leakage ventilation resistance coefficient (R) is calculated according to the resistance relation of the parallel air channelsl)11. The variation of each resistance of the louvers is shown in table 1.
The relation between each resistance value and the opening area of the air window when the air window ventilates
For quantifying the ventilation resistance coefficient (R) of leakagel)11, plotting the air window leakage ventilation resistance coefficient (R)l)11 and the opening area 8 of the air window, and the relationship expression of curve synthesis is
Step 6: determining total windage (R) of a windage window ventilation processt): step 3, step 4 are respectively used for solving the opening ventilation resistance coefficient (R) in the actual ventilation process of the air windowo)10 and coefficient of leakage ventilation resistance (R)l)11, calculating formula according to total wind resistance of parallel wind paths
The total wind resistance is determined.
Knowing the total wind resistance of the wind window, measuring the wind pressure on two sides of the wind window by using a pitot tube, and calculating the total wind resistance of the wind window according to a formula
And finally, obtaining the working theoretical air quantity of the air window.
And 7: comparing the actually measured air volume with the theoretical air volume: recalculating the air quantity by using the total resistance value of the air window, and comparing the result with the measured value Q of the actually improved air window structuremIn comparison, the difference between the calculated value and the measured value was less than 10% as shown in the following table. The method has sufficient reliability within the error range of actual underground measurement.
Actually measuring the air quantity, calculating the relation between the air quantity and the opening area of the air window when the air window is ventilated
Therefore, the total resistance of the air window is used to calculate the air quantity again, and the result is compared with the actual measurement value QmIn comparison, the difference between the calculated value and the measured value was less than 10% as shown in the following table.The equation has sufficient reliability within the error range of actual underground measurements.
Therefore, compared with the traditional method, the wind window structure design and the wind window accurate wind quantity calculation method provided by the invention have higher accuracy.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solutions of the present invention and not for limiting the same, and although the present invention is described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that: modifications and equivalents may be made to the embodiments of the invention without departing from the spirit and scope of the invention, which is to be covered by the claims.
Claims (8)
1. A colliery of accurate definite air volume adjusts wind window includes four bibliographic categories: sliding assembly, window, wind speed sensor, auxiliary component.
2. The coal mine adjusting air window capable of accurately determining the ventilation volume according to claim 1, wherein the sliding assembly is composed of a sliding rail, a synchronous belt and a speed measuring rod.
3. The coal mine adjusting air window for accurately determining the ventilation volume according to claim 2, wherein for accurately determining the relationship between the speed distribution condition of each point of the opening area of the air outlet window and the average speed, simulation software FLUENT is utilized to perform multiple simulations according to the actual size of the mine adjusting air window, and finally the speed at 2/3h (h refers to the height of the air window) is closest to the average speed of the whole ventilation area, wherein the speed is determined to be positioned at the central axis of the ventilation area and is positioned in the upward and downward directions.
4. The coal mine adjusting air window capable of accurately determining the ventilation volume according to claim 3, is characterized in that a speed measuring rod is arranged on a sliding rail, the moving distance of the air window is 2 times of the moving distance of the speed measuring rod according to the working principle of a synchronous belt, the speed measuring rod is always kept at the middle position of the opening area of the air window, a mark is arranged at the position of 2/3h (h refers to the height of the air window) in the upward and downward directions of the speed measuring rod, and a wind speed sensor is placed at the position in actual production.
5. The coal mine adjusting air window capable of accurately determining the ventilation volume according to claim 4, wherein the speed measured by the air speed sensor is multiplied by the ventilation area of the air window, and finally the accurate air volume at the ventilation area of the air window is determined.
6. The coal mine adjusting air window capable of accurately determining the ventilation volume according to claim 5, is characterized in that theoretical analysis is combined with actual data, accuracy verification is carried out on air volume obtained by calculation of known air speed and air window ventilation area, and the specific steps are as follows:
the method comprises the following steps: establishing an open draft resistance coefficient (R)o) Coefficient of leakage ventilation resistance (R)l) Two parallel air paths;
step two: determining the total resistance coefficient of the ventilation process of the air window according to the existing formula;
step three: determining the leakage ventilation resistance coefficient (R) according to the relation between each resistance value and the opening area during ventilationl) An expression;
step four: coefficient of known open draft resistance (R)o) Coefficient of leakage ventilation resistance (R)l) And finally determining the total resistance of the wind window during working.
7. The coal mine adjusting air window capable of accurately determining the ventilation volume according to claim 6, wherein the theoretical air volume value is finally determined by using the obtained total resistance value of the adjusting air window and the measured air pressure of a pitot tube required by a mine.
8. The coal mine adjusting air window for accurately determining the ventilation volume according to claim 7, wherein the final error value between the theoretical air volume value and the air volume calculated by using the speed sensor is within 10%, which indicates that the method for calculating the air volume passing through the opening area of the air window by the adjusting air window is more correct.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN111579194A (en) * | 2020-05-12 | 2020-08-25 | 中煤科工集团重庆研究院有限公司 | Method and system for measuring wind control effect of mine wind window |
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