avskiljningsflöde

Avskiljningsflöde, often translated as separation flow or cutout flow, is a concept primarily used in fluid dynamics, particularly in the context of aerodynamic surfaces like wings or diffusers. It refers to a portion of the fluid flow that is deliberately diverted or extracted from a main flow stream. This diversion is typically achieved through a slot or a series of holes in the surface.

The primary purpose of creating an avskiljningsflöde is to control or manipulate the behavior of the main flow. In aerodynamics, this is frequently employed to prevent or delay flow separation. Flow separation occurs when the fluid detaches from the surface, leading to a loss of lift, increased drag, and reduced efficiency. By bleeding off a small amount of the boundary layer, which is the thin layer of fluid closest to the surface, the main flow can be re-energized and encouraged to stay attached for longer.

This technique is also utilized in other engineering applications. For instance, in gas turbine engines, avskiljningsflöde can be used to cool turbine blades by drawing cooler air from the outer parts of the engine and directing it over the hot blades. In diffusers, it can help to maintain attached flow and improve pressure recovery. The design and placement of the avskiljningsflöde are critical to its effectiveness, and they are often determined through detailed computational fluid dynamics (CFD) analysis and experimental testing. The amount of fluid extracted is usually a small percentage of the total flow, making it an efficient method for flow control.