Research on Sensor Layout of Average Wind Speed Point Location in Roadway Based on LDA

Obtaining the average wind speed of the roadway through the reasonable arrangement of the wind speed sensor is the key technology to realize the intelligent monitoring and control of mine ventilation. In order to solve the core problem in the technology, the Laser Doppler Anemometer (LDA) was used to test the full-section wind flow velocity field of the rectangular roadway. With the consideration of the turbulent fluctuation characteristics of the underground wind flow, the relationship between the wind speed at any point of the roadway with the average wind speed of the section was studied. The research shows that when the wind flow field environment of the roadway is the same and the wind flow is fully developed turbulent state, the distribution law of the average wind speed of the same roadway section has nothing to do with the inlet ventilation wind speed. At this time, the time-averaged wind speed value of the wind speed sensor (<${\nu}_{i}$>) placed on the average wind speed distribution curve is directly equal to the average wind speed of the section ($(\bar{\nu})$). Moreover, <${\nu}_{i}$>is approximately proportional to $(\bar{\nu})$, the conversion coefficient k(k=<${\nu}_{i}$>$/(\bar{\nu})$) is constant, and the structure of the dimensionless velocity field of the roadway is approximately constant. That is, the distribution of k values is constant. At this time, when the wind speed sensor is arranged at any position, the average wind speed of the roadway can be obtained through the coefficient k conversion. When the airflow of the roadway changes, the conversion coefficient k needs to be re-calibrated to obtain, which provides a reference for the layout of the sensor at the position of the average wind speed point in the roadway.