Gas atomization is widely employed for the production of metallic powders used in powder metallurgy and additive manufacturing due to its high productivity and ability to generate fine particle size distributions. In this work, the aerodynamic behaviour of a close-coupled gas atomizer was investigated through computational fluid dynamics (CFD) simulations developed in ANSYS Fluent 2026. A steady-state, single-phase, two-dimensional axisymmetric model of the nozzle assembly was implemented. Supersonic argon flow was simulated for inlet pressures ranging from 20 to 80 bar, discharging into an environment maintained at 1.5 bar. The simulations aimed to evaluate gas flow characteristics, jet plume morphology and mass flow rate through the atomization nozzle.