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为了进一步提高综采工作面空气幕隔尘效率,提出采用新型旋转风幕进行隔尘。根据冲击射流相关理论,推导出了垂帘合理安装位置及垂吊高度。利用旋风分离理论,导出了旋转风幕所能控制的最大粉尘粒径和隔尘效率表达式。借助模型试验,对旋转风幕隔尘下的综采工作面粉尘质量浓度分布及旋转风幕的隔尘效率进行了分析。结果表明:采用旋转风幕隔尘时,空气幕气流在煤壁侧形成一旋转风幕,采煤机滚筒割煤所产生的粉尘在该旋转风幕的卷吸作用下,被控制在煤壁侧,并被工作面风流带走;由于垂帘的阻隔作用,空气幕气流冲击顶板后只能往煤壁方向运动,阻止了空气幕将卷吸进来的粉尘带到采煤司机的工作区,提高了空气幕的隔尘效率;旋转风幕隔尘时,司机侧的粉尘质量浓度较普通空气幕隔尘时进一步降低,其粉尘质量浓度由78 mg/m~3降低至69 mg/m~3,粉尘隔尘效率由81.8%提高至84.2%,提升了2.4%;旋转风幕对呼吸性粉尘的隔尘优势更为明显,司机侧呼吸性粉尘质量浓度由14 mg/m~3降至8 mg/m~3,呼吸性粉尘隔尘效率高达92.6%,较普通空气幕提高了6.5%;旋转风幕对不同粒径粉尘的隔尘效率有差异,随粉尘粒径增加,旋转风幕的隔尘效率不断下降。
In order to further improve the efficiency of air curtain dust separation in fully mechanized coal mining face, a new type of rotating air curtain is proposed to remove dust. According to the related theory of impinging jet, the reasonable installation position and hanging height of vertical curtain are deduced. Based on the theory of cyclone separation, the expression of the maximum dust particle size and the dust separation efficiency that can be controlled by the rotating air curtain is derived. With the model test, the dust concentration distribution of the fully mechanized coal mining face and the dust collection efficiency of the rotating air curtain were analyzed. The results show that air curtain flow forms a rotating air curtain on the side of the coal wall when the air curtain is used to clean the air. The dust generated by the shearer drum cutting coal is controlled by the entrainment of the rotary air curtain, Due to the blocking effect of the vertical curtain, the impact of the curtain air flow on the roof can only move toward the coal wall, preventing the air curtain from taking the entrained dust to the work area of the coal mining driver and improving The efficiency of dust separation of the air curtain was reduced. When dust was applied to the rotating air curtain, the concentration of dust on the driver’s side further decreased when dust was removed from the air curtain. The dust concentration was reduced from 78 mg / m 3 to 69 mg / m 3 , Dust dust efficiency increased from 81.8% to 84.2%, an increase of 2.4%; rotary air curtain dust respirator dust advantage is more obvious, the driver side respirable dust mass concentration from 14 mg / m ~ 3 down to 8 mg / m ~ 3, dust respirable dust efficiency up to 92.6%, compared with ordinary air curtain increased by 6.5%; rotating air curtain on different particle size dust dust efficiency differences, with the dust particle size increases, Dust removal efficiency continues to decline.