附壁风筒径向流量比及抽尘距离对综掘工作面隔尘风幕的影响

摘要

To clarify the effects of wind-splitting ratio of a wall-attached air duct and dust exhaust distance on the air curtain formation and dust barrier effectiveness in the fully mechanized working area,3down610 fully mechanized working face in Jiangzhuang coal mine was developed.The airflow migration and dust diffusion for various wind-splitting ratios (50％-90％) and dust exhaust distances (2-5m) were numerically simulated by Ansys CFD.The results showed that the increase of wind-splitting ratio and decrease of dust exhaust distance are both conducive to the formation of effective dust barrier air curtain.For 3do~610 fully mechanized working face and those working faces with similar production conditions,an effective dust barrier air curtain can be formed under the parameters of both the wind-splitting ratio-80％ with dust exhaust distance-2m and wind-splitting ratio-90％ with dust exhaust distance-2-3m.For these parameters,the high concentration dust can be blocked within the area 7.5m from the working face.The measured results indicate that simulation results generally agree with each other in terms of air flow direction,the average relative error of air flow velocity is less than 13％.By applying the optimal parameters,the average total dust concentration and average respiratory dust concentration in measured section 7m away from the working face are decreased to 18.6mg/m3 and 8.lmg/m3,respectively.It demonstrates that the dust barrier effect is significant.%为明确附壁风筒径向流量所占压风总量的比例及抽风筒的抽尘距离对综掘区域隔尘风幕形成及隔尘效果的影响,以蒋庄煤矿3下610综掘工作面为研究对象,运用Ansys CFD软件对附壁风筒径向流量比例为50％～90％、抽尘距离为2～5m条件下的风流运移及粉尘逸散情况进行数值模拟分析.结果显示,径向流量比例的增加、抽尘距离的降低,有利于在综掘区域形成有效隔尘风幕.针对3下610综掘工作面及与其生产条件相似的其他煤矿综掘工作面,当径向流量比例为80％、抽尘距离为2m以及径向流量比例为90％、抽尘距离为2～3m时,能够形成有效隔尘风幕并将高浓度粉尘阻隔于距迎头7.5m以内的空间范围内.现场实测数据表明,风流运移模拟结果与风流实测结果基本一致、风流流速平均相对误差低于13％,模拟结果较为准确.最优风幕参数条件下,距迎头7m实测断面处,平均总尘浓度降至18.6mg/m3,平均呼尘浓度降至8.1 mg/m3,隔尘效果较为明显.