粘弹性岩石凿力-凿深特性和能量传递研究

Study of Force-Penetration Characteristic and Energy Transfer of Viscoelastic Rock

针对冲击钻进过程中粘弹性岩石力-凿深特性和能量传递问题进行了研究,得出了杆体活塞模型情况下的冲击凿深函数和力-凿深曲线,进一步分析了其能量传递过程和效率。结果表明,弹粘性岩石的力-凿深曲线受速度阻尼的影响,随着粘度增大,其初始力从0点逐渐抬高,最大凿深umax逐渐变小;由于岩石粘性耗能的原因,传递到岩石中的总能量ER加大,最大凿深减少,凿入效率降低。

The force-penetration characteristic and energy transfer of viscoelastic rock in percussive drilling has been studied, resulting in the penetration function of rigid piston model and force-penetration curve. Then the energy transfer process and its efficiency were all analyzed. The force-penetration curve of elastic viscous rock showed that with an influence of the velocity damping, the initial force gradually increased from 0 with an increase in the viscosity, while the maximum penetration depth （ umax ） gradually decreased. Due to viscous dissipation of rock, the total energy （ ER ） being transferred to rock increased with a decrease in the maximum penetration depth, resulting in a lower penetration efficiency.