Droplet impacts are rarely normal to the target substrate druing thermal spray processing because of droplet dispersion in the spray cone or because the substrate is moving. A model for drople tspreading and solidification after off-normal impact on a cold substrate was developed. This model is based on Madejski's energy conservation model but uses a three-dimensional velocity field, which satisfies the no slip condition at the solid front, the no shear condition at the free surface as well as the continuity equation. Furthermore, the present model assumes the shape of the spreading droplet to have a non-axisymmetric shape (limacon perimeter and a uniform height). Stefan solidification is assumed. A mechanical energy balance is resulting integro-differential equation is solved numerically using a modified Euler predictor-corrector method, This model was validated by comparison with existing energy-conservation models in the case of normal impact. The results indicate both a decrease in the final splat impact. The resutls indicate both a decrease in the final splat impact. The results indicate both a decrease in the final splat diameter and a decrease in the expansion rate of the spreadifng droplet as the impact angle increases, as measured from the normal axis. The resulting impacts are therefore less efficient as the impact angle increases.
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