U型通风工作面采空区漏风影响因素研究

发布时间：2018-07-28 11:57

【摘要】：漏风是导致采空区遗煤自燃的主要原因之一,同时也对采空区内瓦斯涌出具有重要影响,因此研究工作面采空区漏风意义重大。论文主要研究工作面不同通风和瓦斯抽采条件对采空区漏风的影响,分析各个因素对工作面采空区漏风的影响,并根据分析结果制定相应的对策。基于"O"型圈冒落压实和非线性渗流理论,建立了采空区内流场数学模型;采用专业的流体力学模拟软件fluent对刘庄矿151305工作面采空区漏风流场进行了数值模拟,结合刘庄矿该工作面实际开采条件,反演得到采空区渗透率分布模型,并对工作面采空区漏风流场和渗透率分布进行分析。结果表明:该工作面采空区流场分布符合"O"型圈特征,漏风范围在工作面倾向0～160m,其中0-20m范围内漏风最为严重;采空区渗透率下降最快区域在距开切眼煤壁走向0-15m和距进、回风侧煤壁倾向0-15m范围内,工作面后方走向0-70m范围次之,其他区域渗透率基本不变;工作面自然危险区域为采空区进风侧走向25-95m和回风侧走向15-120m。在工作面采空区漏风现状模拟的基础上,分别模拟分析了高抽巷瓦斯抽采、工作面供风量及工作面风阻对采空区漏风的影响。根据模拟结果,拟合得到采空区漏风量与高抽巷瓦斯抽采量、工作面供风量及工作面风阻之间分别为指数、三次函数和一次函数关系。通过分析得出,高抽巷瓦斯抽采量和工作面供风量分别存在对采空区漏风量影响的临界值,并分析得到该工作面临界值的大小。若高抽巷瓦斯抽采量和工作面供风量小于其临界值,则对采空区漏风影响最大的是工作面风阻,其次是工作面供风量,最小是高抽巷抽采量;若高抽巷瓦斯抽采量和工作面供风量大于其临界值,则对采空区漏风影响最大的是工作面供风量,其次是高抽巷瓦斯抽采量,最小是工作面风阻。另外,对工作面采空区漏风范围也进行了考察,结果表明,高抽巷瓦斯抽采量、工作面风量和风阻对工作面漏风范围有一定影响,其值越大,漏风范围也越大,其中高抽巷瓦斯抽采量最为明显。
[Abstract]:Air leakage is one of the main causes of coal spontaneous combustion in goaf, and it also has an important influence on gas emission in goaf, so it is of great significance to study the air leakage in goaf of working face. This paper mainly studies the influence of different ventilation and gas extraction conditions on the air leakage in goaf, analyzes the influence of various factors on the air leakage in goaf, and formulates corresponding countermeasures according to the analysis results. Based on the theory of "O" ring caving compaction and nonlinear seepage, a mathematical model of the flow field in goaf is established, and the leakage flow field in goaf of 151305 working face in Liuzhuang Mine is numerically simulated by the professional fluid dynamics simulation software fluent. Combined with the actual mining conditions of the working face in Liuzhuang Mine, the permeability distribution model of the goaf is obtained by inversion, and the air leakage field and permeability distribution in the goaf are analyzed. The results show that the distribution of flow field in goaf of this face accords with the characteristics of "O" circle, the air leakage range is 0 ~ 160 m in the face, and the air leakage is the most serious in the range of 0-20 m, the fastest decrease of permeability in the goaf is in the distance of 0-15 m from the coal wall of the open cut hole and the distance into the coal wall. Within the range of 0-15m, the back direction of the coal face is 0-70m, the permeability of other areas remains unchanged, and the natural dangerous area of the face is the gob air side strike 25-95m and the backwind side strike 15-120m. On the basis of the simulation of the air leakage in the goaf of the working face, the effects of the gas drainage in the high drainage roadway, the air supply rate and the air resistance on the air leakage in the goaf are simulated and analyzed respectively. According to the simulation results, the relationship between air leakage in goaf and gas extraction in high drainage roadway is obtained. The relationship between air supply and air resistance is exponential, cubic function and primary function respectively. Through analysis, it is concluded that the critical value of gas extraction and air supply in high drainage roadway has influence on the air leakage in goaf, and the critical value of this face is obtained by analysis. If the amount of gas extraction and air supply in high drainage roadway is less than its critical value, the biggest influence on the air leakage in goaf is the air resistance in the face, the next is the air supply in the working face, and the minimum is the high drainage volume in the roadway. If the amount of gas drainage and the amount of air supply in the working face are greater than the critical value, the biggest influence on the air leakage in the goaf is the air supply in the face, the next is the amount of gas drainage in the high drainage roadway, and the minimum is the air resistance in the working face. In addition, the scope of air leakage in the goaf of working face is also investigated. The results show that the amount of gas drainage, the amount of air and the air resistance of the face have certain influence on the scope of air leakage of the face, and the larger the value, the bigger the scope of air leakage. Among them, high drainage roadway gas drainage is the most obvious.
【学位授予单位】：安徽理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TD728

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