Calculation and sensitivity analysis of convective heat transfer coefficient between roadway wall and airflow

In order to accurately calculate the convective heat transfer coefficient between the mine roadway air flow and the roadway wall, according to the heat and moisture exchange principle between the roadway air flow and the roadway wall, and considering the actual production conditions of the mine such as the wet roadway wall, the humid air of the roadway air flow and the roughness of the roadway wall, the convective heat transfer coefficient is expressed as the wind temperature, wind speed, moisture rate, roadway size, roadway wall temperature, thermal physical parameters and friction resistance coefficient. Based on the expression of convective heat transfer coefficient, the sensitivity of convective heat transfer coefficient to the three factors of roadway wind speed, roadway radius and roadway friction resistance coefficient is mainly discussed by using sensitivity analysis method. The results show that the sensitivity of the three factors is significantly different, among which the wind speed of the roadway is the most sensitive factor affecting the convective heat transfer coefficient, and the sensitivity of convective heat transfer coefficient to roadway friction resistance coefficient is second, and the sensitivity of convective heat transfer coefficient to the roadway radius is the lowest. When the roadway radius changes within a certain range, the convective heat transfer coefficient is less sensitive to the roadway radius, and its influence on the heat transfer coefficient can be ignored at this time.