摘要
为了改善反向扩孔气动冲击器长距离扩孔性能,从其结构和工作原理出发,建立工作过程数学模型和由冲击器排气孔到其后封头的排屑流场模型,运用微分数值求解和有限元方法,对其工作过程和气固两相流场进行仿真计算,并进一步优化长距扩孔时冲击器钻头结构参数,得到冲击器性能随扩孔距离变化曲线,排屑流场出口岩屑浓度分布规律和不同钻头结构参数时流场出口最大颗粒浓度变化情况。研究结果表明:随着扩孔距离的增长,应该增大冲击器入口压力;钻头排气孔直径D=28 mm、排气孔角度β=16°和出屑口直径d_1=60 mm时排屑流场岩屑浓度低于5%,岩屑能够顺利排出孔外。
In order to improve the long distance reaming ability of the back-reaming pneumatic impactor, the mathematical model of the work process and the model of rock debris removal flow fields from the exhaust hole to the impactor were established base on the structure and work principle, the numerical differentiation and finite element method were utilized to do simulation calculation of the work process and the gas-solid two-phase flow field.Furthermore, the structure parameter of the drill was optimized to suit long reaming. As a result, the impactor performance curve with the changing of reaming distance, the particle concentration distribution at outlet section of the field and the maximum particle concentration of outlet section under the condition of different drill structure were obtained. The results show that, the inlet pressure should be in creased with the increase of reaming distance. while the diameter of exhaust hole in the drill is 28 mm, the angle of the exhaust hole is 16 °, the diameter of clearance hole is 60 mm, the maximum volume fraction of rock debris is less than 5% and can successfully removal out the channel annular.
出处
《凿岩机械气动工具》
2016年第2期29-36,共8页
Rock Drilling Machinery & Pneumatic Tools
基金
国家自然科学基金资助项目(51375499)
关键词
钻头结构参数
岩屑浓度
反向扩孔气动冲击器
数值模拟
structure parameters of the drill
particle concentration
back-reaming pneumatic impactor
numerical simulation
