Gas-Particle Two-Phase Jet Flow from Slot Nozzle and Micro-Blasting Process

Recently, the micro-blasting process has been widely used to process brittle material, and a conventional circular nozzle has been commonly used. But the cutting performance of a circular nozzle does not process a large area well, so the use of a slot nozzle is considered. In this study, in order to improve the cutting performance of the micro-blasting nozzle, a new slot nozzle with a large aspect ratio is proposed and the flow characteristics and cutting performance are examined precisely by experimental and numerical analyses. The main results show that (1) setting the circular vane in the slot nozzle perpendicular to the stream can diffuse particle flow uniformly at the nozzle exit, making the particle velocity distribution uniform, (2) expanding the nozzle outlet at an angle, uniform air and particle velocity distributions at the nozzle exit can be obtained, (3) in spite of setting obstacles at the nozzle, a fine cutting efficiency is obtained compared to the conventional micro-blasting circular nozzle.