Träfikströmmen

Träfikströmmen refers to the movement of vehicles, cyclists, pedestrians and other users through a transportation network. The term is commonly used in Swedish traffic engineering and planning to describe both the instantaneous flow of traffic at a specific location and the overall dynamics of traffic over larger regions. It is measured in terms of volume (number of units per hour) and speed (kilometres per hour) and is often expressed as flow rate, a product of density and velocity.

In traffic theory Träfikströmmen is analyzed at both macroscopic and microscopic levels. Macroscopic models treat the traffic stream as a continuous fluid, using equations such as the Lighthill‑Whitham‑Richards model to relate speed, density and flow. Microscopic models simulate individual vehicle behavior, accounting for acceleration, braking, lane changing and driver reaction. The combination of these models enables planners to predict congestion, evaluate the impact of network changes and optimise signalised intersections.

Several factors influence Träfikströmmen, including road capacity, geometric layout, signal timing, driver behaviour, vehicle mix and external conditions such as weather or incidents. An efficient Träfikströmmen results in reduced travel times, lower fuel consumption and fewer emissions, while poorly managed flow leads to bottlenecks and increased risk of accidents.

Swedish authorities employ a range of tools—from loop detector networks to GPS‑based probe data—to monitor and manage Träfikströmmen in real time. These data feed into traffic management centres, where adaptive signal control and traffic information systems are deployed to maintain optimal flow conditions across the network.