Air knife

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An air knife is normally used in manufacturing or as the first step in a recursive recycling process to separate lighter or smaller particles from other components for use in later or subsequent steps, post manufacturing parts drying and conveyor cleaning, part of component cleaning. The knife consists of a high intensity, uniform sheet of laminar airflow sometimes known as streamline flow.

When a fluid flows in parallel layers, with no disruption between the layers it has laminar characteristics.

Fluid dynamics: Laminar flow is a flow regime characterized by high momentum diffusion, low momentum convection, and pressure and velocity independence from time. It is the opposite of turbulent flow. The dimensionless Reynolds number characterizes whether flow conditions lead to laminar or turbulent flow.

Aeronautics: Air flowing over an aircraft wing. The boundary layer is a very thin sheet of air lying over the surface of the wing, as well as all other surfaces of the craft. Because air has viscosity, this layer of air tends to adhere to the wing. As the wing moves forward through the air, the boundary layer at first flows smoothly over the streamlined shape of the airfoil. In this aspect the flow is called laminar or the laminar layer.