注氮条件下不同抽采负压对采空区氧化宽度影响

摘要

针对正行煤矿1502综放工作面开采具有高瓦斯易自燃的特点，现场进行采空区“三带”测试，并对测试数据进行分析．运用气体渗流理论通过 FLUENT6．3模拟了注氮的同时改变高抽巷抽采负压情况下采空区瓦斯浓度场、漏风场、氧气浓度场．通过 FLUENT 模拟技术，观察高抽巷不同抽采负压与回风巷上隅角瓦斯浓度大小之间的关系，并建立这种关系的拟合方程，计算出回风巷上隅角瓦斯浓度不超限时的最低抽采负压．根据模拟的注氮条件下不同负压抽采时漏风场和氧浓度场等值线图绘制出采空区自燃“三带”的划分图．得到了不同抽采负压与自燃带宽度之间的关系，并将这种线性关系拟合成方程，从而确定了高抽巷抽采负压的最佳范围，既可以预防上隅角瓦斯超限，又防止了采空区遗煤自燃事故的发生．%According to the high gas and easy hypergolic features of 1502 working face,the field of goaf of“three zones”is tested,and the test data is analyzed.Based on the technology of FLUENT simulation,it changes the negative pressure of high drainage roadway under nitrogen injection condition,analyzes the goaf air leaking field,gas concentration field and oxygen volume fraction after simulation.It observes the relation between different negative pressure and upper corner gas density,builds the fitted equation,and works out the lowest drainage negative pressure when the condition of upper corner gas density does not exceed the limit. According to the simulative contour map of air leaking field and oxygen density field in different drainage pressure under the condition of nitrogen injection,the paper gets the relation between different drainage negative pressure and spontaneous combustion zone,and matches the equation.Thus,the paper ensures the best range of high drainage roadway negative pressure which can prevent upper corner gas over -linit and coal spontaneous combustion accidents from happening in the goaf.