Numerical Simulation of Scale Removal from Mine Drainage Pipe by Water Jet

Abstract

ABSTRACT To study the process of coal mine drainage pipe scale removal by using a water jet and its affecting parameters, a numerical model based on the fluid-solid interaction method is developed to simulate the removal process. The grid of the water jet and null material adopts ALE (Arbitrary Lagrange-Euler) formulation, while the pipe scale grid employs Lagrange formulation. The water jet penetration is simulated by coupling ALE fluid elements and Lagrange solid elements. The stress variation inside the pipe scale under the impact of water jet is analyzed. In addition, the effect of water jet parameters on the cutting depth is investigated. The numerical results are consistent with the experimental results. The results illustrate that the impact velocity and the incident angle of water jet have a significant influence on the impact depth determination. Small impact velocity causes erosion near the pipe scale surface and the actual crush occurs only when the velocity exceeds a certain value. The incident angle of water jet has an efficient range and larger cutting depths can be obtained as the incident angle increases up to 70°.