Optimisation of the gas atomisation process used in aluminium powder production : To improve morphology by minimising satellite formations

Abstract: There exists a lack of information and an exact understanding of the gas atomisation process resulting in the use of trial and error methods in the industry. The lack of information is the result of the difficulties in observing the actual process as it occurs, something that the use of computational fluid dynamics may be able to substitute. This thesis investigates the possible use of computational fluid dynamics simulations applicability in understanding and improving the process. The focus is on how the characteristics of the gas flow change when the pressure is changed between 4.5 to 12 bar. The geometry of the gas atomiser used in this thesis was based on Gränges ABs’production unit. The results show that a large vortex was created on the left side of the wall for all pressures.The findings in this thesis can be compared with Gränges ABs gas atomiser or gas atomisers with similar geometry. If correlations are found between the simulation and spray runs then the improvements stated in this thesis can be applied in order to lower the presence of satellites, improving circularity in produced metal powders.