Track Calculation and Numerical Simulation on Particles in High Pressure Abrasive Water Jet Nozzle

The high pressure water jet nozzle is a key part to accelerating abrasive particles. The geometrical model of fluid control volume in front and back nozzle and physical model of particle were established by object oriented fluid flow flied and particle of submerged jet. The results showed that the outlet average velocity of fluid and particle falls down sharply with the particle concentration increasing. The speed sliding ratio of particle is 0.9-0.93. Because the particles in nozzle had not been completely accelerated, the velocity was accelerated continuously until the two phase velocities are equal. The best particle concentration was 3%-8% in cutting material. The cutting capacity was affected remarkably by particle size, but the outlet velocity descends with increasing of particle´s diameter. The best particle diameter is 1/3-1/4 of nozzle´s exit diameter.