| Abstract: |
Cold spray is the latest technique to provide a coating by jetting supersonic flow with solid-powder onto a substrate. In the cold spray, the impinging velocity of the particle is the dominating factor to control the mechanical and chemical characteristics of the coating. In order to obtain an accurate particle velocity by computation, the gas flow must be solved within an acceptable accurately. In the field of computational fluid dynamics, it is well recognized that when calculating the turbulent nozzle flow with flow separation that several computational grids must be provided within a laminar sub-layer to obtain a reliable solution. It is expected that the smallest grid size has a remarkable effect on the separated flow, which is often seen in the cold spray nozzle. However, from the practical point of view, the influence of the grid size on the particle velocity is not well known.
This paper tries to clarify the influence of grid size on the particle flow, as well as the gas flow, in the cold spray nozzle. The influence of the smallest grid size in the radial direction on the supersonic gas/particle nozzle flow is investigated.
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