Flödeskanaler

Flödeskanaler, or flow channels, are conduits that guide the movement of fluids from one location to another. They can be natural or artificial and include both open channels and closed conduits. The concept covers scales from micrometres in microfluidics to kilometers in river networks.

Natural flow channels are shaped by the transport of water and sediment, driven by gravity and climate. They form networks that drain landscapes, transport nutrients, and influence erosion and sediment deposition. Channel geometry—cross-sectional shape, width, depth—along with slope and roughness determines flow velocity and regime (laminar or turbulent).

Engineered channels include irrigation ditches, drainage canals, stormwater sewers, and pipes used in water supply or chemical processing. In microfluidics, channels fabricated from glass, silicon, or polymers direct and manipulate small fluid volumes for assays and lab-on-a-chip devices. Cross-sections can be rectangular, circular, or more complex, and surface properties influence wetting and capillary effects.

Key concepts and equations used to describe flow in channels include the Manning equation for open-channel flow and the Darcy-Weisbach equation for closed conduits, along with conservation of mass and momentum. Dimensionless numbers such as Reynolds, Froude, and Capillary numbers help classify flow regimes and dominant forces. Design and management considerations cover discharge capacity, erosion control, sediment transport, habitat quality, and flood risk.

Flödeskanaler are central to hydrology, ecology, civil engineering, and biotechnology due to their role in transport, distribution, and processing of fluids.