长距离掘进巷道爆破粉尘非稳态分布规律

Unsteady distribution law of blasting dust in long distance driving roadway

为了指导通风系统和防尘系统的设计,以马堡煤矿152采区轨道下山掘进工作面为背景进行爆破后的CFD模拟研究,并结合实际测量,以获得粉尘扩散规律、粉尘粒径沉降规律和粉尘浓度时间变化规律。模拟结果显示:距离地表垂高为0.5 m处粉尘浓度最高,距地表4 m处粉尘浓度最低。粒径在90~200μm的几乎完全沉降;15μm以下的长时间悬浮;10μm以下的粉尘均匀分布于沿程空间各点。在1~5 min之内,大颗粒迅速沉降;粉尘浓度5 min后开始逐渐减小。距掘进工作面10~20 m范围内粉尘浓度一直保持在较高水平。现场实测得到距工作面20 m和25 m范围内的粉尘浓度分布规律与数值模拟结果基本一致。

In order to guide the design of ventilation system and dust control system,taking the driving roadway in No.152 mining area of Mabao Coal Mine as the background,the CFD simulation study after blasting was carried out.Combined with the actual measurement,the dust diffusion rule,dust particle size settlement rule and dust concentration variation rule were obtained.The simulation results show that the dust concentration is the highest at the height of 0.5 m from the surface and the lowest at the height of 4m from the surface.The dust with a particle size of 90~200μm is almost completely settled,suspended for a long time under 15μm,and evenly distributed at all points in the space under 10μm,large particles settle rapidly within 1~5 min,and dust concentration gradually decreases after 5 min,and the dust concentration has been maintained at a high level within 10~20 m from the heading face.The distribution of dust concentration in the range of 20~25 m from the driving face is basically consistent with the numerical simulation results.