Numerical simulation study on the impact of high-voltage electric pulses on rock breaking during drilling

Abstract:

As the demand for deep resource exploration increases， high-voltage electric pulse rock-breaking technology has emerged as a focal research area in the drilling field， driven by its efficiency and environmental advantages. This study first establishes a multi-physical field coupling model for high-voltage electric pulse rock-breaking drilling. Three distinct drill bit configurations are designed， including coaxial cylindrical， multi-electrode pair， and electrode-crossing arrangements. Simulation were conducted to investigate the impact of drill bit electrode structures on the effectiveness of high-voltage electric pulse rock-breaking， identifying the optimal electrode configuration under identical electrical parameters and rock characteristics. Based on the optimal coaxial cylindrical electrode structure， further simulations were performed to examine how factors such as drill bit diameter， applied voltage， high-voltage electrode shape， and rock dielectric constant influence the electric field strength within and on the surface of the rock. The results demonstrate that the coaxial structure provides a more concentrated electric field distribution， with the fracture area expanding more evenly from the center to the outer layers. Therefore， the coaxial structure exhibits distinct advantages for rock breaking. Additionally， the study reveals the influence of drill bit diameter and other factors on the electric field distribution both on the surface and within the rock. This research provides a critical design basis for optimizing high-voltage electric pulse rock-breaking drill bits， offering valuable guidance for advancing the practical application of this technology in engineering contexts.