综掘工作面通风条件对径向旋流风幕阻尘效果的影响

Influences of ventilation conditions of fully mechanized excavation face on dust-resistance effect of radial swirling air curtain

为了提高综掘工作面径向旋流风幕阻尘效率,降低高浓度粉尘对人员作业区域污染,运用数值模拟与工程实测相结合的方法分析了通风条件对径向旋流风幕阻尘的影响规律。结果表明:随着风幕与工作面距离增加,风幕装置径向风量增大、通风系统压抽比减小,径向旋流风幕运移过程中更易于转化为风量与风速分布均匀的轴向阻尘流场,粉尘污染程度随之降低。拟合了高浓度粉尘扩散距离与各通风条件间的定量关系,结合实际生产条件,确定了径向旋流风幕阻尘较优通风条件为风幕距工作面30 m,风幕装置径向风量为270 m3/min以及通风系统压抽比为0.8。通过对模拟结果进行工程实测,验证了数值模拟的有效性,掘进司机断面粉尘浓度降至35.5 mg/m3,风幕阻尘效率达到了90.5%。

In order to improve the dust-resistance efficiency of radial swirling air curtain in fully mechanized excavation face and prevent high-concentration dust pollution on the working area,the method of combining numerical simulation and engineering measurement is used to analyze the influences of ventilation conditions on dust-resistance rule of radial swirling air curtain.The results show that as the distance between the air curtain and the working face increases,the radial air volume of the air curtain device increases,and the pressure-exhaust ratio of the ventilation system decreases,the radial swirling air curtain is easier to transform into an axial direction with uniform air volume and velocity distribution during the migration process,and the dust pollution degree reduces as well.Fitting the quantitative relationship between the high-concentration dust diffusion distance and various ventilation conditions,combined with the actual production conditions,it is determined that the better ventilation conditions for the radial swirling air curtain dust resistance are as following:the air curtain is 30 m away from the working face,the radial air volume of the air curtain device is 270 m3/min and the pressure-exhaust ratio of the ventilation system is 0.8.Through engineering measurement of the simulation result,the validity of the numerical simulation was verified.The dust concentration ofthe tunneling driver’s section was reduced to 35.5 mg/m3,and the air curtain dust resistance efficiency reached to 90.5%.