Research On Wind Speed Measurement Technology Of Irregularly Roadway

Mine ventilation is an essential auxiliary system for safe coal mine production,and is an important measure to prevent and control various underground disasters and ensure safe coal mine production.After excavation,the roadway is affected by a variety of factors,the shape of the section is mostly deformed,and the accurate monitoring of the roadway wind speed is difficult to meet.In this paper,we use a combination of theoretical analysis,numerical simulation and field test to study the wind speed distribution law and the location of the average wind speed point in irregular roadway sections,and the main research work is as follows:Through theoretical research,the common deformation types of underground coal mine roadway sections are introduced,the characteristics of roadway wind flow distribution are analyzed,the functional model of wind speed variation characteristics parallel to the centerline direction of the section is established based on Plante turbulence mixing length theory and Boussinesq theory,the functional model conforms to the logarithmic functional form,and the 3D section scanning technology is introduced to provide methodological guidance for efficient and accurate measurement of roadway wind volume.A model of semi-circular arch and trapezoidal roadway commonly found in underground coal mines is established,and the irregularity of roadway deformation is replaced by concave and convex hemispheres,and the wind speed distribution law of irregular roadway section under different conditions(entrance wind speed,section size,hemisphere size,hemisphere position,hemisphere number)is simulated and studied,and it is obtained that the wind speed value inside the concave body is very small and has almost no effect on the wind speed distribution of the section,and the wind speed distribution of the roadway section The wind speed distribution of the roadway section is related to the size of the roadway section,the size of the convex body,the location of the convex body and the number of convex bodies,and is not related to the entrance velocity.By fitting the wind speed values on the central axis of the roadway section with the distance from the roadway wall,the wind speed and the distance from the roadway wall conform to the logarithmic function relationship,when the convex body size is less than 200 mm,the distance of the average wind speed point on the central axis of the roadway from the roadway wall is 0.11 times of the roadway width or height,and when the convex body size is greater than 200 mm,at the relatively regular wall,the average wind speed point on the central axis of the roadway from the The distance from the wall of the roadway is 0.1 times the width or height of the roadway.Taking Taoyuan mine as the field test site,the regular and irregular sections of the roadway were selected,and the location of the measurement points were determined according to the width and height of the roadway section measured on site,and the average wind speed of the roadway section was measured,and the wind speed error was within 5% when comparing the fixed-point method and the line method.The laser three-dimensional scanner is used to measure the roadway cross-sectional area,and the roadway wind volume is accurately obtained according to the average wind speed and area of the roadway cross-section.Figure 56 Table 35 Reference 71...