U型通风采空区注氮参数优选

现场实测了某矿工作面采空区的氧气浓度分布，并利用反演的方法确定了更符合现场实际的基础参数，模拟得到的氧气浓度分布与实测数据基本吻合，以确定的基础参数为条件，利用FLUENT软件对U型通风方式下采空区注氮防灭火技术参数进行了研究。研究结果表明:注氮量相同的条件下，注氮口位置不同时的采空区氧气浓度分布规律也不尽相同，其所达到的防灭火效果也不一样，对比分析自燃“三带”及考虑相应的安全回采速度，确定了最佳注氮口位置为进风侧距工作面10m处；注氮口位置相同时，随着注氮量的增加，采空区自燃带不断回缩前移，自燃带宽度越来越小，通过比较模拟结果及参照相关判定条件，确定了注氮口为10m时的最佳注氮量180m3/h。

Optimization of nitrogen inject parameter for U-shaped ventilation goaf

The oxygen concentration distribution in working face was measured, and the inversion method was applied to determine the actual parameters. The oxygen concentration distribution by simulation coincided basically with the experimental data. Taking the determined basic parameters for condition, the nitrogen inject parameter of U type ventilation goaf was studied with the application of FLUENT software.The research results showed that the oxygen concentration distribution was different with different nitrogen injection port location under the same nitrogen injection JP2quantity, and the fire prevention effect was different also. By comparision and analysis of spontaneous combustion “three zones” and considering the corresponding safety mining speed, the optimum loction was determine to be 10 m from the working face in the inlet side. With the same inject location,spontaneous combustion “three zones” retracted forward continuously when nitrogen injection quantity increased.At last ,the optimum nitrogen injection volume was 180m3/h by comparing the simulation results and referring to related determination conditions.