Spatial distribution and migration law of respirable dust in fully mechanized mining face
陈向军叶向阳李毅博左沛琪
CHEN Xiangjun;YE Xiangyang;LI Yibo;ZUO Peiqi
河南理工大学 瓦斯地质与瓦斯治理国家重点实验室培育基地河南理工大学 安全科学与工程学院
针对粉尘采样器测尘法只能对固定作业地点的粉尘质量浓度进行测定,无法系统反映工作面粉尘质量浓度的空间分布特征和运移规律的问题;以柠条塔煤矿N1219综采工作面为研究对象,采用离散相与连续相双向耦合的方法,利用Fluent软件对综采工作面的呼吸性粉尘(以下称“呼尘”)的空间分布及运移规律进行三维数值模拟。模拟结果表明:采煤机侧呼尘粒径普遍高于液压支架侧,考虑到由于支架侧风流向采空区时存在漏风现象导致风流的搬运能力减弱,携带呼尘粒径较小;滚筒割煤产生的呼尘,在工作面走向上呈现出2个阶段,距进风巷70~120 m区间为快速下降区段,距进风巷120~280 m区间为缓慢下降区段;在工作面走向上的呼尘最高质量浓度可达1 600 mg/m3;在工作面倾向方向上,距煤壁越远,滚筒割煤产生的呼尘质量浓度越低,在距煤壁4~5 m处呼尘质量浓度递减至0,在80~280 m区段,移架产生的呼尘全部集中在液压支架侧,在40~240 m区段,通风携带的呼尘质量浓度在工作面高度方向分布均匀。
For the problem that the dust sampling method can only measure the dust mass concentration at fixed working locations, and can not systematically reflect the spatial distribution characteristics and migration rules of the dust mass concentration in the working face, taking the N1219 fully mechanized mining face of Ningtiaota Coal Mine as the research object, a three-dimensional numerical simulation was conducted on the spatial distribution and transport law of respirable dust (hereinafter referred to as “exhaled dust”) in the fully mechanized mining face using Fluent software, using the method of bidirectional coupling between discrete and continuous phases. The simulation results show that the particle size of dust particles on the side of the shearer is generally higher than that on the side of the hydraulic support. Considering that there is air leakage when the air flow on the support side flows towards the goaf, the carrying capacity of the air flow is weakened, and the particle size of dust particles carried is smaller; the dust generated by drum coal cutting presents two stages in the direction of the working face: the section between 70 m and 120 m from the intake airway is a “rapid descent section”, and the section between 120 m and 280 m from the intake airway is a “slow descent section”. In addition, the maximum mass concentration of dust generated in the direction of the working face can reach 1 600 mg/m3; in the inclined direction of the working face, the farther away from the coal wall, the lower the dust mass concentration generated by the drum cutting coal, and the dust mass concentration decreases to 0 mg/m3 at a distance of 4-5 m from the coal wall; in the section from 80 m to 280 m, all the dust generated by moving the frame is concentrated on the side of the hydraulic support; in the range of 40 m to 240 m, the mass concentration of exhaled dust carried by ventilation is evenly distributed in the height direction of the working face.
综采工作面CFD模拟呼吸性粉尘浓度分布运移规律
fully mechanized mining face;CFD simulation;respiratory dust;concentration distribution;movement rules
主办单位:煤炭科学研究总院有限公司 中国煤炭学会学术期刊工作委员会