| Abstract Scope |
Dry aerosol deposition (DAD) enables the fabrication of dense ceramic coatings at room temperature through high-velocity particle impact. While nozzle geometry is a key factor governing gas–particle dynamics, its direct influence on coating densification requires further investigation. This work presents a comparative study on the performance of a baseline slit nozzle versus modified converging–diverging designs using a combined computational and experimental approach.
Three-dimensional Computational Fluid Dynamics (CFD) simulations (COMSOL Multiphysics) are used to analyze flow characteristics and particle trajectories for 1–10 μm aluminosilicate particles. The study focuses on evaluating how changes in nozzle profile affect critical parameters such as particle impact velocity and spatial distribution at the substrate. To validate these predictions, coatings are deposited on low-carbon steel substrates using the corresponding nozzle geometries.
Coating properties, including thickness, morphology, and porosity, are characterized via profilometry, SEM, and dye-penetration testing. The objective of this research is to identify geometric features that minimize flow recirculation and maximize kinetic energy transfer. By correlating simulation data with experimental coating quality, this study aims to provide design guidelines for improving deposition efficiency in the DAD process. |