ADJUSTMENT FOR THE OPTIMUM DISTRIBUTION OF DUST AND GAS IN FULLY MECHANIZED HEADING FACE

The forcing type ventilation at the current fully mechanized heading face is inadequate to meet the requirement of underground coal mine, which could lead to serious disaster of dust and gas explosion and environmental pollution in the roadway. In this paper, the airflow field, dust field and gas field at different distances from the duct outlet to the heading face were numerically simulated, the formation mechanism of each field and the reasons of unreasonable distribution were analyzed, an airflow adaptation adjustment method was proposed for realizing the optimal distribution of airflow, dust and gas by comprehensively changing the position, caliber and direction angle of the duct outlet. The method was applied to Ningtiaota coal mine in Northern Shaanxi of China. The adjustment schemes obtained with airflow adaptability adjustment method provided better results when prepared to before optimization. The dust concentration at the driver position decreased by 35% and the gas concentration reduced by 54%, which provides a theoretical basis for the scientific management of ventilation in the fully mechanized heading face.