空隙率对潜孔锤凿岩瞬态冲击过程的影响

潜孔锤的钻进过程是一个高度非线性、大变形、破碎岩石的过程,利用非线性有限元程序ANSYS/LS-DY-NA研究了在凿岩过程中,球齿凿入不同空隙率（塑性体积应变）岩石的冲击力特性。结果表明,岩石空隙率对钻头球齿与岩石之间的凿入冲击力幅值有很大影响,随着空隙率的增大,球齿凿入的冲击力显著减小,而对活塞与钻头间冲击力幅值影响甚微。通过ANSYS/LS-DYNA瞬态冲击数值模拟,形象地再现了潜孔锤钻凿系统冲击岩石发生侵入破坏的物理过程,为冲击碎岩瞬态研究提供了一个有效的分析方法。

Simulation Study of Rock Voids Rate Affecting on Impact Force of DTH Hamme

The process of impact hammer drilling is very complex for high non-linearity,large deformation and damage behavior.The explicit finite element code ANSYS/LS-DYNA was employed to research the transient percussive characteristic of bit＇ inserts impacting brittle rock with different rate of air voids.The impact forces curves of concrete and sandstone under hammer impact has been recorded.From the simulation results,the rock void rate affects variously on the transient impact force of bit＇ inserts penetrating rock.The impact force between bit and rock decreases sharply as the rock void rate rises.However,the transient impact force between piston and bit has nothing with the rock void rate.The physical processes such as insert penetrating rocks subjected to percussive hammer drilling are displayed visually.It is believed that the numerical simulation will become a good research method for transient impact process.