Study on flow field characteristics and calculation of local ventilation resistance coefficient for turning areas of roadway

This paper presents results of a computational fluid dynamics (CFD) study, based on which a mathematical model is developed to calculate the local ventilation resistance coefficient of roadway turning areas. The turning areas of two return airways, namely Jizhong return airway and Shangsitou return airway in Wangpo Coal Mine were selected as the study areas. From the CFD model, the pressure distributions in the roadway turning areas and the local pressure loss along the turning areas were analyzed. The simulation results were then compared with field measurements and empirical formula to calculate ventilation resistance in roadway turning areas. The results indicate that the CFD simulation can accurately simulate local ventilation resistance in roadway turning areas. Combining numerical analysis with CFD simulation results, a formula was established to calculate the local ventilation resistance coefficient from air flow and turning angle in turning area of roadways. The results show that the ventilation pressure loss along roadway turning areas is “front big wave peak-back wavelets peak” double wave peak type. This local resistance mathematical model for roadway turning areas could be used to predict the ventilation resistance of newly developed curved roadways,and could also provide accurate wind resistance parameters for the calculation of mine air network.