顺煤层钻孔风力排渣临界风速及压力损失研究  

Study on Critical Air Velocity and Pressure Loss of Pneumatic Coal Dust Removal for Boreholes along Coal Seams

作　　者：牛国庆[1,2] 张伟[3] 

机构地区：[1]河南理工大学安全科学与工程学院,河南焦作454000 [2]河南省瓦斯地质与瓦斯治理重点实验室-省部共建国家重点实验室培育基地,河南焦作454000 [3]河南省地质矿产勘查开发局第一地质矿产调查院,河南洛阳471000

出　　处：《中国安全科学学报》2013年第11期60-65,共6页China Safety Science Journal

基　　金：国家"973"项目资助(2012CB723103)

摘　　要：为探讨顺层钻孔钻进过程中风量和压力对排渣能力的影响,基于气固两相流理论,结合气力输送的经验及半经验公式,计算顺煤层钻孔风力排渣过程中钻屑颗粒群的临界风速。利用FLUENT数值模拟软件模拟钻孔风力排渣过程,得到不同固气比对应的临界风速,并对比计算、数值模拟与文献模拟试验3项结果,最后根据流体力学相关理论计算风力排渣的压力损失。结果表明:当钻屑粒径一定时,排渣所需的临界风速随着固气比的增大呈对数关系增大,两相流的压力损失也随之增大;气流在钻杆内孔中的压损是两相流在环空体中压损的数十倍,系统提供的能量大部分消耗在钻杆内孔中。In order to study the influence of mass of air and pressure on the ability of pneumatic slagoff for boreholes along coal seams, the theoretical critical air velocity of the group of cuttings coal dust was calculated based on the theory of gas-solid two-phase flow combined with the empirical and semi-empirical formula of pneumatic conveying. Then FLUENT was used to simulate the process of pneumatic coal dust removal in boreholes to get the critical air velocities corresponding to different solid-gas ratios. Comparisons were made among the results of calculation, numerical simulation and simulation experiment. Finally, the pressure loss of the pneumatic coal dust removal was calculated based on fluid mechanics theory. The results show that there is a logarithmic relationship between the critical velocity of coal particles and solid- gas ratios, and pressure loss of two-phase flow increases proportional to it, and that the pressure loss of gas in the hole of drill pipe is ten times of two-phase flow, and the large part of pressure energy is consumed in the hole of drill pipe.

关 键 词：顺层钻孔 气固两相流 风力排渣 临界风速 数值模拟 

分 类 号：X964[环境科学与工程—安全科学] TD713[矿业工程—矿井通风与安全]