Coal mine underground roadway wind speed measuring method based on ultrasonic time difference method

Abstract

The invention discloses a coal mine underground roadway wind speed measuring method based on an ultrasonic time-difference method, which adopts a mode that an ultrasonic transmitting and receiving probe A is fixed at the top of one side and an ultrasonic transmitting and receiving probe B moving along a vertical track is arranged on the other side. And calculating the roadway wind speed when the ultrasonic transceiving probe B moves to different point positions to obtain the average wind speed on a plurality of straight lines, and averaging the average wind speed on the straight lines to obtain the average wind speed of the section of the measured roadway, so that the detection accuracy of the wind speed of the underground roadway of the coal mine is improved.

Description

Technical Field

[0001] This invention relates to the field of mine ventilation, and in particular to a method for measuring wind speed in underground coal mine roadways based on ultrasonic time-of-flight method. Background Technology

[0002] Ventilation in underground coal mine roadways is the lifeline for ensuring operational safety and efficiency. Proper ventilation is crucial for preventing the accumulation of coal mine gas, removing dust and harmful gases, and supplying oxygen to underground workers to ensure their safety. Therefore, accurate measurement of roadway wind speed is the top priority in ventilation management.

[0003] In related technologies, the wind speed distribution in different roadways is affected by the roadway cross-sectional shape, roadway support type, and equipment layout within the roadway. Due to the pulsating characteristics of roadway airflow and the non-uniform distribution of wind speed across the roadway cross-section, accurate wind speed measurement is difficult. Traditional methods for measuring wind speed in coal mines use mechanical anemometers, employing the nine-point or twelve-point method to approximate the average wind speed across the roadway cross-section. With the increasing demands for accuracy, frequency, and efficiency in wind volume measurement due to the development of intelligent coal mines, traditional wind measurement methods are becoming increasingly inadequate to meet these requirements.

[0004] Regarding the aforementioned technologies, when using the mechanical wind gauge for wind speed measurement, the presence of accumulated debris, pipes, belt conveyors, and other underground equipment in the roadway can affect the wind measurement work, resulting in low accuracy of the measured data. Summary of the Invention

[0005] To improve the accuracy of wind speed detection in underground coal mine roadways, this application provides a method for measuring wind speed in underground coal mine roadways based on ultrasonic time-of-flight method.

[0006] This application provides a method for measuring wind speed in underground coal mine roadways based on ultrasonic time-of-flight method, employing the following technical solution: A method for measuring wind speed in underground coal mine roadways based on ultrasonic time-of-flight method includes the following steps: S1; An ultrasonic transceiver probe A is fixed at the top of one side of the tunnel, and a vertical track is arranged on the other side. The tunnel cross-section where the ultrasonic transceiver probe A is located is not on the same cross-section as the tunnel cross-section where the vertical track is located. An ultrasonic transceiver probe B that can move up and down is installed on the vertical track. S2; The vertical track is divided into n points at equal intervals along its height direction. The points on the vertical track from bottom to top are set as 1, 2, 3...n. Control the ultrasonic transceiver probe B to move to the 1st point on the vertical track. S3; Adjust the angles of ultrasonic transceiver probe A and ultrasonic transceiver probe B to bring them into a direct-fire state so that the ultrasonic signal strength reaches its maximum value. S4; Ultrasonic transceiver A transmits ultrasonic signals, ultrasonic transceiver B receives ultrasonic signals, and records the time difference between ultrasonic transmission and reception. t ab Ultrasonic transceiver probe B emits ultrasonic signals, and ultrasonic transceiver probe A receives the ultrasonic signals, recording the time difference between ultrasonic transmission and reception. t ba ; S5; Measure the distance L between ultrasonic transceiver probe A and ultrasonic transceiver probe B, and then measure the angle α between the sound wave direction and the airflow direction. S6; Measured ultrasonic transceiver time t ab and t ba Given the distance L and the included angle α, calculate the linear wind speed along the line connecting the ultrasonic transceiver probe B and the ultrasonic transceiver probe A at this point. S7; Control the ultrasonic transceiver probe B to move on the vertical track to the 2nd, 3rd...nth point, repeat steps S3 to S6, calculate the wind speed in the tunnel when the ultrasonic transceiver probe B moves to different points, obtain the average wind speed on the n straight lines, and then calculate the average value of the average wind speed on these straight lines to obtain the average wind speed of the measured tunnel cross section.

[0007] Optionally, in S6, the calculation formula is: V The average wind speed along the straight line between ultrasonic transceiver probe A and ultrasonic transceiver probe B; where V The unit for L is m / s, and the unit for L is m. t ab and t ba The unit is s.

[0008] Optionally, in S5, both ultrasonic transceiver probe A and ultrasonic transceiver probe B integrate a laser rangefinder and an angle measuring device.

[0009] Optionally, in S5, the distance L between ultrasonic transceiver probe A and ultrasonic transceiver probe B is ≥10:1 for the tunnel width.

[0010] In summary, this application includes at least one of the following beneficial technical effects: 1. By adopting a method of fixing ultrasonic transceiver probe A on the top of one side and setting ultrasonic transceiver probe B that moves along the track on the other side, the unfavorable conditions for wind measurement, such as belt conveyors, pipelines, and debris accumulation in the tunnel, are effectively overcome. 2. By using the ultrasonic time-of-flight method to measure wind speed, the wind speed in the roadway is calculated when the ultrasonic transceiver probe B moves to different points, and the average wind speed on several straight lines is obtained. Then, the average wind speed on these straight lines is used to calculate the average wind speed of the measured roadway cross section, which improves the accuracy of wind speed detection in underground roadways of coal mines. Attached Figure Description

[0011] Figure 1 This is a schematic diagram showing the location of the tunnel and the vertical track.

[0012] Figure 2 This is a schematic diagram of ultrasonic transceiver probe A and ultrasonic transceiver probe B conducting ultrasonic transceiver tests.

[0013] Figure 3 This is a schematic diagram showing the connection between the vertical track and the ultrasonic transceiver probe B.

[0014] Explanation of reference numerals in the attached diagram: 1. Ultrasonic transceiver probe A; 2. Ultrasonic transceiver probe B; 3. Vertical track; 31. Slide groove; 32. Slider; 33. Bolt. Detailed Implementation

[0015] The present application will be further described in detail below with reference to all the accompanying drawings.

[0016] This application discloses a method for measuring wind speed in underground coal mine roadways based on ultrasonic time-of-flight method. Example

[0017] Reference Figure 1 and Figure 2 A method for measuring wind speed in underground coal mine roadways based on ultrasonic time-of-flight method includes the following steps: S1; An ultrasonic transceiver probe A1 is fixed at the top of one side of the roadway, and a vertical track 3 is arranged on the other side. The cross-section of the roadway where the ultrasonic transceiver probe A1 is located is not on the same cross-section as the cross-section of the roadway where the vertical track 3 is located. An ultrasonic transceiver probe B2 that can move up and down is installed on the vertical track 3. Both the ultrasonic transceiver probe A1 and the ultrasonic transceiver probe B2 are GFC15 type mining ultrasonic wind speed sensor transceiver probes, which can realize the functions of ultrasonic transmission and reception, as well as recording the ultrasonic transmission and reception time. Reference Figure 3 To enable the ultrasonic transceiver probe B2 to move to different points on the vertical track 3, a groove 31 can be provided along the length of the vertical track 3. The ultrasonic transceiver probe B2 is mounted on a slider 32, and the ultrasonic transceiver probe B2 is rotatably connected to the slider 32, allowing for angle adjustment of the ultrasonic transceiver probe B2. The slider 32 slides within the groove 31. When the slider 32 slides to a certain point, a bolt 33 can be used to pass through the slider 32 and abut against the inner wall of the groove 31, thus positioning the slider 32 within the groove 31.

[0018] S2; The vertical track 3 is divided into n points at equal intervals along its height direction. The points on the vertical track 3 from bottom to top are set as 1, 2, 3...n. The ultrasonic transceiver probe B2 is controlled to move on the vertical track 3 to the first point. S3; Adjust the angles of ultrasonic transceiver probe A1 and ultrasonic transceiver probe B2 to adjust them to the opposite-beam state so that the ultrasonic signal strength reaches the maximum value. S4; Ultrasonic transceiver probe A1 transmits ultrasonic signals, ultrasonic transceiver probe B2 receives ultrasonic signals, and records the ultrasonic transmission and reception time difference tab; Ultrasonic transceiver probe B2 transmits ultrasonic signals, ultrasonic transceiver probe A1 receives ultrasonic signals, and records the ultrasonic transmission and reception time difference tba; The time difference between ultrasonic transceiver probe A1 and ultrasonic transceiver probe B2 can be calculated using the GFC15 type mining ultrasonic wind speed sensor transceiver probe.

[0019] S5; Measure the distance L between ultrasonic transceiver probes A1 and B2. The distance L: roadway width ≥ 10:1 to improve measurement accuracy. Next, measure the angle α between the sound wave direction and the airflow direction. The sound wave direction refers to the direction of sound wave transmission between ultrasonic transceiver probes A1 and B2. Both ultrasonic transceiver probes A1 and B2 integrate a laser ranging device and an angle measuring device. The laser ranging device uses a YHJ200 intrinsically safe mine-use laser rangefinder, which can measure the distance between ultrasonic transceiver probes A1 and B2. The angle measuring device uses a GUD360 intrinsically safe mine-use angle sensor, which can measure the angle between the ultrasonic transmission direction and the airflow direction.

[0020] S6; Measured ultrasonic transceiver time t ab and t ba 、 Given the distance L and the included angle α, the linear wind speed along the line connecting the ultrasonic transceiver probe B2 and the ultrasonic transceiver probe A1 at this location is calculated using the following formula: The average wind speed along the line of sight between ultrasonic transceiver probe A1 and ultrasonic transceiver probe B2 was obtained. V ;in V The unit for L is m / s, and the unit for L is m. t ab and t ba The unit is s.

[0021] S7; Control the ultrasonic transceiver probe B2 to move on the vertical track 3 to the 2nd, 3rd...nth point, repeat steps S3 to S6, calculate the wind speed in the tunnel when the ultrasonic transceiver probe B2 moves to different points, obtain the average wind speed on the n straight lines, and then calculate the average value of the average wind speed on these straight lines to obtain the average wind speed of the measured tunnel cross section.

[0022] When calculating the average wind speed of the above-mentioned tunnel cross-section, the calculated wind speed values ​​at points 1, 2, 3...n are respectively set as follows: V 1. V 2. V 3… V n The average wind speed of the tunnel cross section is set as V The formula for calculating the average wind speed across the tunnel cross section is: V The unit of ' is m / s.

[0023] The implementation principle of the ultrasonic time-of-flight method for measuring wind speed in underground coal mine roadways, as described in this application, is as follows: An ultrasonic transceiver probe A1 is fixed at the top of one side of the roadway, while an ultrasonic transceiver probe B2, moving along a vertical track 3, is installed on the other side. Using the ultrasonic time-of-flight method, the wind speed in the roadway is calculated when the ultrasonic transceiver probe B2 moves to different points, resulting in several average wind speeds along straight lines. These average wind speeds are then averaged again to obtain the average wind speed of the measured roadway cross-section. This method, employing a fixed and moving ultrasonic sensor, achieves accurate detection of wind speed within the roadway cross-section. This detection method offers higher accuracy, frequency, and efficiency than traditional methods. It changes the traditional "point-to-area" wind measurement method, significantly improving measurement accuracy. Furthermore, it overcomes the obstacles posed by underground equipment, pipelines, and debris accumulation in coal mine roadways, improving the environmental applicability of the wind speed detection method.

[0024] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A method for measuring wind speed in underground coal mine roadways based on ultrasonic time-of-flight method, characterized in that, Includes the following steps: S1; An ultrasonic transceiver probe A (1) is fixed at the top of one side of the tunnel, and a vertical track (3) is arranged on the other side. The tunnel cross section where the ultrasonic transceiver probe A (1) is located is not on the same cross section as the tunnel cross section where the vertical track (3) is located. An ultrasonic transceiver probe B (2) that can move up and down is installed on the vertical track (3). S2; The vertical track (3) is divided into n points at equal intervals along its height direction. The points of the vertical track (3) from bottom to top are set as 1, 2, 3...n. Control the ultrasonic transceiver probe B (2) to move to the first point on the vertical track (3); S3; Adjust the angles of ultrasonic transceiver probe A (1) and ultrasonic transceiver probe B (2) to make ultrasonic transceiver probe A (1) and ultrasonic transceiver probe B (2) be in the opposite direction so that the ultrasonic signal strength reaches the maximum value. S4; Ultrasonic transceiver probe A (1) transmits ultrasonic signals, ultrasonic transceiver probe B (2) receives ultrasonic signals, and records the time difference between ultrasonic transmission and reception. t ab The ultrasonic transceiver probe B (2) transmits ultrasonic signals, and the ultrasonic transceiver probe A (1) receives ultrasonic signals, recording the time difference between ultrasonic transmission and reception. t ba ; S5; Measure the distance L between ultrasonic transceiver probe A (1) and ultrasonic transceiver probe B (2), and then measure the angle α between the sound wave direction and the wind flow direction. S6; Measured ultrasonic transceiver time t ab and t ba Given the distance L and the included angle α, calculate the linear wind speed along the line connecting the ultrasonic transceiver probe B(2) and the ultrasonic transceiver probe A(1) at this location. V ; S7; Control the ultrasonic transceiver probe B (2) to move on the vertical track (3) to the 2nd, 3rd...nth point, repeat steps S3 to S6, calculate the wind speed in the roadway when the ultrasonic transceiver probe B (2) moves to different points, obtain the average wind speed on n straight lines, and calculate the average value again from the average wind speed on these straight lines to obtain the average wind speed of the measured roadway cross section.

2. The method for measuring wind speed in underground coal mine roadways based on ultrasonic time-of-flight method according to claim 1, characterized in that: In S6, the calculation formula is: V Let A be the average wind speed along the line of sight between ultrasonic transceiver probe A (1) and ultrasonic transceiver probe B (2); where V The unit for L is m / s, and the unit for L is m. t ab and t ba The unit is s.

3. The method for measuring wind speed in underground coal mine roadways based on ultrasonic time-of-flight method according to claim 1, characterized in that: In S5, both ultrasonic transceiver probe A (1) and ultrasonic transceiver probe B (2) are integrated with laser ranging devices and angle measuring devices.

4. The method for measuring wind speed in underground coal mine roadways based on ultrasonic time-of-flight method according to claim 1, characterized in that: In S5, the distance L between ultrasonic transceiver probe A (1) and ultrasonic transceiver probe B (2) is ≥10:1 for the tunnel width.

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