Simulation Model for Traffic Using Network Fundamental Diagrams

Traditionally, traffic is described at the level of an individual vehicle (microscopic) or at the level of a link (macroscopic). This paper introduces a traffic flow simulation model at a higher, subnetwork scale. The network is split in cells (subnetworks), and for each of the cells the Network Fundamental Diagram (NFD) is determined. Each time step, the flow from one cell to another is determined by the NFD, separated in a demand and a supply. For the demand, the border capacity between two cells plays a role. Opposed to the cell transmission model, the demand is decreasing for overcritical accumulation in cell i due to accumulation effects. This model can be used to quickly determine effects of network wide traffic control.