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The correction method of air velocity transducer in underground mine roadway

As the air velocity is unevenly distributed in the underground mine roadway section, the hanging position and correction method of air velocity transducer have seriously affect the monitoring accuracy. In order to improve the air velocity monitoring accuracy, this paper ascertains 4 main impacted factors including section shape, section height, section width and average value of air velocity. Combining with the computational fluid simulation technology, the orthogonal test method and the dimensionless approach, the distribution of air velocity are analyzed in the vertical midline of the roadway section. The applications show that the best hanging position of air velocity transducer is the 0.8 times relative height from the bottom border, and the correction formula is ν' = 0.9573 ν + 0.0027. It can provide the protection for realizing the automation of mine ventilation optimization and control.