1.Mine Safety Branch, China Coal Research Institute, Beijing , China;2.State Key Laboratory of Coal Mining and Clean Utilization,Beijing , China

为了揭示掘进期间综掘巷道内瓦斯分布变化规律，以新郑煤电有限责任公司12205上副巷综掘工作面为研究对象，基于达西渗流定律建立了综掘工作面煤层瓦斯动态渗流模型，采用有限体积法求解得到综掘巷道煤层瓦斯压力场与瓦斯解吸速率场，在此基础上分析推导了掘进进尺周期内与掘进支护周期内综掘工作面各瓦斯涌出源的瓦斯涌出速率公式，基于CFD动网格技术建立了综掘工作面瓦斯扩散非稳态计算模型，研究了掘进过程中综掘巷道内瓦斯浓度场时空演化过程，研究结果表明：掘进进尺周期内综掘工作面内瓦斯浓度无明显的增大或减小趋势，掘进支护周期内综掘工作面内瓦斯浓度呈现明显的减小趋势，通过现场数据实测验证了数值模拟结果的可靠性。

In order to reveal the distribution varied law of the gas in the fully-mechanized heading gateway during the heading period, taking the fully-mechanized heading face of No.12205 upper entry in Xinzheng Coal and Electric Power Company Limited as a study object, based on a Darcy seepage law, a dynamic seepage model of the seam gas in the fully-mechanized heading face was established. A finite volume method was applied to solute and obtain the seam gas pressure field and gas desorption rate field of the fully-mechanized heading gateway. Based on the circumstances, the gas emission rate formula of each gas emission source in the fully-mechanized heading face within heading advance period and the heading support period was analyzed and reduced. Based on the CFD dynamic grid technology, a gas diffusion unsteady calculation model of the fully-mechanized heading face was established and was applied to study the time-space evolution process of the gas concentration field within the fully-mechanized heading gateway during the heading process. The study results showed that the gas concentration within the fully-mechanized heading face during the heading advance period would be no obviously increased or decreased. Within the heading support period, the gas concentration in the fully-mechanized heading face was obviously reduced in tendency. The reliability of the numerical simulation results was proved by the site data measured.