CFD research on particle movement and nozzle wear in the abrasive water jet cutting head

Particle velocity and movement in the high-pressure abrasive water jet (AWJ) heading are significant jet properties which deserve a better understanding for improving AWJ machining performance. In this paper, particle acceleration and movement trajectory in the jet field within AWJ cutting head were conducted based on the Euler-Lagrange approach and the discrete particle model (DPM) from a computational fluid dynamics (CFD) simulation study. The particle inlet position, particle inlet angle, and converge angle of focus tube were taken into consideration in the physical model. The models were then assessed qualitatively and quantitatively by previous experiment data. The results indicated that a particle inlet located at a high position could increase particles’ exiting velocity and decrease nozzle wear. A steeper abrasive feed angle would improve the particle acceleration process and reduce radial velocity, resulting in less nozzle weight loss. The effects of converging part angle were analyzed as well. The obtained results would improve the machine efficiency of the workpiece, extend nozzle lifetime, and guide the future design of AWJ nozzle.