超细气溶胶颗粒在典型综采工作面采空区扩散规律研究

Study on the Diffusion Law of Ultrafine Aerosol Particles in Goaf of Typical Fully Mechanized Mining Face

为了研究超细气溶胶颗粒在地下受限空间的防灭火潜力,通过CFD数值模拟手段研究了粒径为1~20μm的5种超细气溶胶颗粒在典型综采工作面采空区内部的运移扩散规律。结果表明:颗粒粒径与颗粒最大有效扩散距离及最大停滞时间呈负相关关系,1μm粒径颗粒的最大扩散范围和最大停滞时间最佳,分别为210.48m和2212106s,超细颗粒注入位置对颗粒在采空区内部的运移扩散有显著影响,进风隅角的涡流中心对其有着两面性的影响;超细颗粒的注入压力与扩散范围呈正相关关系,与颗粒的停滞时间呈负相关关系,注入压力为2.25MPa时颗粒注入效果最好,其颗粒在采空区内最大停滞时间为3429449s,最大有效扩散范围为198.32m;采空区空隙率与超细颗粒的扩散范围呈正相关关系,空隙率为0.2时,最大扩散范围最小为49.99m,空隙率为0.4时,最大扩散范围最大为119.88m。研究结果可为矿井火灾防治提供理论参考。

In order to study the fire prevention and extinguishing potential of ultrafine aerosol particles in underground confined space,the migration and diffusion rules of five kinds of ultrafine aerosol particles with particle size of 120μm in the goaf of typical fully mechanized mining face were studied by CFD numerical simulation.The results show that the particle size is negatively correlated with the maximum effective diffusion distance and the maximum stagnation time of the particles.The maximum diffusion range and the maximum stagnation time of the particles with a particle size of 1μm are 210.48mand 2212106s,respectively.The injection position of ultrafine particles has a significant influence on the migration and diffusion of particles in the goaf,and the vortex center at the inlet corner has a two-sided influence on it.The injection pressure of ultrafine particles is positively correlated with the diffusion range and negatively correlated with the stagnation time of particles.The particle injection effect is the best when the injection pressure is 2.25MPa.The maximum stagnation time of particles in the goaf is 3429449s,and the maximum effective diffusion range is 198.32m.The porosity of the goaf is positively correlated with the diffusion range of ultrafine particles.When the porosity is 0.2,the maximum diffusion range is 49.99m,and when the porosity is 0.4,the maximum diffusion range is 119.88m.The research results can provide a theoretical reference for mine fire prevention and control.