Study on gas transportation principle and control in goaf with Y-shape ventilation system

In order to better grasp the law of gas flow and methane emission under the Y-shape ventilation system,aimed at the Y-shape ventilation system of fully mechanized sub-level caving face,the model of computational fluid dynamics was set up for simulating the flow field of the goaf under Y-shape ventilation system.Through numerical simulation,the characteristics of goaf flow field and gas transportation under Y-shape and U-shape ventilation systems were analyzed.The model and equation were put into the CFD simulation software,the simulation result was obtained and matched very well with lots of practical datas.The results showed that the concentrated air leakage from the goaf to the upper corner can be eliminated by applying Y-shape ventilation system,and the problem of gas accumulation at the upper corner under U-shape ventialtion system and the gas of the return airway can be effectively solved.