论文部分内容阅读
瓦斯在采空区内运移造成工作面上隅角瓦斯超限是煤矿安全的重大隐患。为揭示采空区瓦斯运移规律,提出基于格子Boltzmann的非均质采空区瓦斯运移仿真方法。综放采场采空区是由非均质多孔介质组成的空间,大气和瓦斯混合气体在采空区的流动是非常复杂的具有层流、过度流和紊流的渗流运动。基于修正的Brinkman-Forch-heimer-Darcy定律,建立非均质采空区瓦斯运移的控制方程组。由于该方程组求解复杂,分别建立瓦斯渗流速度场和瓦斯浓度场的格子Boltzmann模型。通过格子Boltzmann模型的演化,实现采空区瓦斯运移的仿真。模拟实例表明,用该方法进行仿真可以得到任何时刻采空区内任意位置瓦斯和大气混合气休的流动速度和压力以及瓦斯浓度等数据,同时也可以得到采空区流线分布规律、速度变化规律、采空区压力的变化规律和采空区瓦斯运移规律。该方法能将时间、空间和系统行为结合起来,可在直观的条件下完成对地下煤矿采空区瓦斯运移态势的精确分析与模拟,可为揭示综放采场采空区上隅角瓦斯超限的原因提供一种新的方法。
Methane in the goaf caused by gas migration in the corner gas overhang is a major hazard in coal mine safety. In order to reveal the law of gas migration in goaf, a simulation method of gas migration in heterogeneous goaf based on lattice Boltzmann was proposed. The goaf of the fully mechanized caving mining stope is a space composed of heterogeneous porous media. The flow of air and gas mixture in the goaf is a very complicated flow with laminar flow, over-flow and turbulent flow. Based on the modified Brinkman-Forch-heimer-Darcy law, the governing equations of gas migration in heterogeneous goaf are established. Due to the complex solution of the equations, the lattice Boltzmann model of gas seepage velocity field and gas concentration field are established respectively. Through the evolution of Lattice Boltzmann model, the simulation of gas migration in goaf is achieved. The simulation results show that the method can be used to simulate the flow rate and pressure of gas and atmospheric gas at any position within the gob at any time and the gas concentration and other data. Law, pressure variation law of goaf and gas movement law in goaf. The method can combine the time, space and system behavior, and can accurately analyze and simulate the gas movement in the underground coal mined area under the condition of intuition. It can be used to reveal the gas in the upper corner of the goaf The reason for the overrun provides a new method.