U型回采工作面回风隅角布置方式对风流流场的影响研究

Effect of layout on the flow field at return corner of U-type working face

为研究矿井工作面回风隅角风流流场与其布置方式之间的关系,应用FLUENT软件,建立回风隅角滞后和正常布置2种几何模型,结合现场相对压力的变化趋势,模拟分析2种模型回风隅角的压力和流场分布情况。结果表明:何家塔煤矿50105工作面回风隅角滞后1.5 m时,其回风隅角相对压力较正常布置时高,且其变化趋势与现场具有较好的一致性;回风隅角支架后方处于最大流速仅为0.16 m/s的涡流中,而正常布置时支架后方最大流速可达0.3~0.45 m/s且涡流范围很小;回风巷外帮附近,回旋流以大于正常布置时约0.2 m/s的速度将附近气体带向回风隅角,但在支架后方的涡流区域,其风流速度又小于正常布置。根据对比分析,回风隅角滞后时,回风隅角处会产生较大范围的涡流,影响有害气体的流散,应尽量避免回风隅角的滞后,或通过改变回风隅角风流流场的方法来防止有害气体积聚。

In order to study the relationship between the flow field and layout in the return corner ot working face, two geometric models of the lagging and normal arrangement of return corner were estab- lished using FLUENT software. Combined with the trend of the field relative pressure ,the pressure distribution and flow field distribution of two models were analyzed. The results show that with 1.5 m lagged of return corner in Hejiata coal mine 50105 working face ,the relative pressure is higher and the trend of the relative pressure is consistent with the measured. The place behind the brackets in the return corner is in the vortexing where the maximum velocity is only 0.16 m/s ,but the maximum velocity is up to 0. 3 - 0.45 m/s and the range of the vortexing is small with the normal layout. The airflow velocity near the wall of the return airway is 0.2 m/s which is more than the normal layout and its direction is to the return corner. However, the velocity is less than the normal layout in the vortex area behind the brackets. According to the comparative analysis ,when the return corner is lagging ,the large amount of vortex will be generated at the return corner,which will affect the dispersion of harmful gases. It is necessary to avoid the lag of the return corner, or to prevent the accumulation of harmful gas by changing the flow field of the return corner.