旋转水射流破岩的数值模拟分析

采用非线性动力有限元和岩石动态损伤模型模拟了旋转水射流作用下岩石的损伤破坏过程 ,其中岩石损伤场的求解采用解耦的方法。同时还对旋转水射流的破岩机理进行了分析。模拟计算结果与前期的试验结果一致 ,均显示旋转射流具有较强的破岩能力 ,其原因在于旋转射流的质点具有三维速度 ,破岩时以倾斜冲击为主 ,易于在岩石表面形成拉伸和剪切破坏 ,回流的干扰较少 ;破岩过程首先是形成一环形破碎带 ,然后沿径向和轴向发展 ,所形成的破碎坑呈内凸锥状。旋转射流破岩的优势在于破碎面积大、效率高。

Numerical analysis on rock-breaking mechanism using swirling water jet

The evolvement of rock damage impacted by swirling water jet was simulated with nonlinear finite element method and dynamic rock damage model. The decoupled method was used to solve the rock damage field. The numerical simulation results agree well with the test result, which indicates that the swirling water jet has relatively strong ability for breaking rock. The rock-breaking mechanism with swirl water jet is that the particle of jet has three-dimensional speed and sloping impact during rock breaking, and the interference of returning fluid on the damage of rock is small. So it is easy to produce and shear fractures on the surface of rock. In the process of rock breaking, an annular broken band is generated on the surface of rock at first, and then the annular band is developed along the radial and axial directions. At last, a hole with a protruding awl is formed at the bottom of broken rock. The swirling water jet technique for breaking rock has good efficiency and larger breaking area.