综采工作面滚筒旋流风对截割煤尘侧向逸散规律的影响

Influence of rotary wind from drums on lateral dissipation law of coal dust from cutting at fully-mechanized mining face

为探究滚筒旋流风对截割煤尘侧向逸散规律的影响,对工作面中风流-煤尘在滚筒旋流风汇入前、后的流动及逸散规律进行数值模拟,并将呼吸带作为一个高度范围分析其平均煤尘质量浓度的分布情况;针对研究结果研发了采煤机雾化封闭式除尘器并通过煤尘质量浓度的实测考察其应用效果,同时验证数值模拟的准确性。结果表明,滚筒旋流风具有很强的稳定性,同时对截割煤尘具有极为明显的诱导作用,其中前滚筒截割煤尘在采煤机中心下风侧14.2 m处的底板附近汇入人行道空间,后滚筒截割煤尘则首先由采煤机中心的底板附近汇入人行道空间,随后在其下风侧2.9 m处的全断面空间大范围涌入。在呼吸带范围的人行道侧,采煤机下风侧18.3～21.8 m为峰值浓度分布区,煤尘质量浓度约为300～400 mg/m^3。初始实测煤尘质量浓度与数值模拟结果对比的相对误差均小于15%;采煤机雾化封闭式除尘器的降尘率为50%～80%,平均降尘率为66.9%。

To explore the law that rotary wind from drums influences on lateral dissipation of coal dust from cutting,this paper simulated the flowing and dissipation law of wind-coal dust before and after rotary wind from drums into the face,and took the breathing zone as a height range to analyze the coal dust concentration distribution.According to the results of the study and research,a shear scrubber was developed,meanwhile,the application effect was investigated and the results of numerical simulation were verified by the measurement of coal dust concentration.Research indicates that the rotary wind from drums has a strong stability and it has very obvious entrainment to coal dust from cutting,the coal dust from TG drum enter into sidewalk by floor at the leeward 14.2 m of center of shear,the coal dust from MG drum enter into sidewalk by floor at the center of shear,soon afterwards,swarming with wide range at the leeward2. 9 m.At the breathing zone of sidewalk,the peak concentration distribution area is located in the leeward 18.3-21.8 m of center of shear,the coal dust concentration is about 300-400 mg/m^3. The relative error of initial measured coal dust concentration compared with the results of numerical simulation is less than 15%. The dust-laying rate of shear scrubber is maintained at 50-80% and its average dust-laying rate is 66.9%.