Abstract
The flow structure of a planar water jet impinging on a solid substrate was studied by means of three-dimensional numerical simulations. In the system studied, the planar water jet issues from a slot nozzle into quiescent air, falls vertically, impinges on a horizontal smooth surface, and then a thin film forms on the solid surface. The liquid flow was assumed to obey the Navier-Stokes equations in three-dimensional Cartesian coordinates. The simulations took into account the effects of gravity, viscosity, and surface tension at the free surface. Experiments were also conducted for model validation. The predictions of the model were in reasonable agreement with the experimental results. The effects of the velocity profile at the nozzle exit, the liquid flow rate, and the nozzle-plate distance on the flow structures were investigated. The physics of these phenomena are discussed in detail from the viewpoint of fluid mechanics.
