Innløpskanter

Innløpskanter are the edges at the entrance of an opening or duct through which a fluid enters, such as an air intake, a pump connection, or a turbine housing. They mark the boundary between the surrounding surface and the flow domain and play a key role in how the flow develops as it transitions from free stream into the duct.

The geometry of innløpskanter influences boundary layer behavior, pressure losses, and flow uniformity. Sharp edges can promote flow separation and distortion near the inlet, while rounded edges or defined lips help to guide the flow more smoothly, reducing losses and improving stability, especially at higher speeds or larger Reynolds numbers. In air intakes for engines, the lip design of the innløpskante affects pressure distribution at the compressor face and can minimize distortion. In hydraulic and marine applications, the edge geometry interacts with the free surface and can impact cavitation risk, intake efficiency, and debris handling.

Design considerations include the radius of curvature, lip thickness, alignment with the main flow, and transitions to adjacent surfaces. Anti-icing, surface roughness, and manufacturing tolerances may also play a role in performance. Engineers assess innløpskanter using computational fluid dynamics (CFD), wind or water tunnel experiments, and in-situ measurements of pressure distribution and flow uniformity.

Related concepts include boundary layer, flow separation, lip or edge, and intake distortion. The term is used across disciplines such as automotive, aerospace, and civil or mechanical engineering to describe the critical entrance characteristics of fluid systems.