CFD modelling of high pressure gas atomization of liquid metals

Abstract

High pressure gas atomization (HPGA) is a technique for the manufacture of fine spherical metal powders. Supersonic gas jets are used to disrupt a stream of liquid metal into droplets which then solidify in flight. We construct a CFD model for gas flow within a gas atomizer which is compared against high-speed video footage of a research scale atomizer. Good agreement between simulation and experiment is found for the presence of Prandtl-Meyer waves on the surface of the spray cone. The simulation also reproduces the location of the recirculation zone below the melt delivery nozzle. Simulation results indicate a radially outward flow from the bore of the melt nozzle to the circumferential edge which would facilitate pre-filming.