Effect of abrasive mass flow rate on energy efficiency in low-pressure supersonic abrasive air jet rock-slitting

The low-pressure supersonic abrasive air jet (AAJ) effectively addresses high containment pressures and hard rock. The energy distribution of the AAJ during travel rock-slitting is primarily influenced by the abrasive mass flow rate, which significantly impacts cutting efficiency. A CFD-DEM model was used to analyze the effects of nozzle travel speed and abrasive mass flow rate on particle velocity and energy distribution. Results indicate that under a constant nozzle travel speed, the impact kinetic energy varies with changes in the abrasive mass flow rate. The increase in abrasive mass flow rate enhances the energy of rock, but an upper limit exists. As nozzle travel speed increases, the optimal mass flow rate also rises. However, higher nozzle speeds reduce cutting efficiency due to shorter jet-rock contact time. Thus, selecting the optimal mass flow rate at lower nozzle speeds is an economical strategy for maximizing rock-breaking performance.